NTX5467

The other suggestions certainly have merit, but I wonder that possibly the catalytic converter might be having a restriction issue at that higher mileage. I believe there's a ball joint connection where the lead pipe joins the pipe just prior to the converter, so it would be easy to take things loose there and see if it makes any difference (with the car parked, of course!).<P>I concur with the comments on the Bosch spark plugs. I never did mind charging a customer full retail when they said the just put some Bosch Platinum plugs in and they wanted some new AC-Delco plugs back in their vehicle. Some of the newer Ultras have Nippondenso Platinums as the OEM spec plug--the replacement AC-Delco box even has the Nippondensos in them too. In any event, where ever you get the AC-Delco plugs from should also be able to get you a set of AC-Delco plug wires too (pre-terminated and ready to install).<P>The other things I can think of that might cause a problem (throttle position sensor, oxygen sensors, etc.) should all set a code in the computer.<P>One other thing might be the change of fuel mixes from cooler weather to warmer weather? Or maybe just a bad tank of gas?<P>In any event, getting the ignition issues sorted out and freshened up would be a good start. Plus running the mentioned pressure checks on the fuel system.<P>Sometimes, a deposit buildup in the throttle body can cause problems, but they are usually related to poor idle quality and lower idle speed. It probably would not hurt to use some carb cleaner on the throttle plates and make sure the Idle Air Control operatives are working as they should. 3M makes a "throttle plate cleaner" and I suspect you can find something similar over there.<P>Once everything's back to snuff, you'll enjoy that Buick again!<P>NTX5467

A non-restrictive (i.e.,. reasonably fresh) fuel filter is of extreme importance for several reasons. Not only does it let full pressure get to the pressure regulator on the injector rail, it also keeps the pump from drawing too much current (sometimes melting or discoloring the insulation on the wires which supply electricity to the pump on the sending unit itself). Usually, when the filter is restricted, the pump will have a louder whine that should be audible away from the vehicle.<P>Any time the pump is changed, a new fuel pump strainer should be installed--period.<P>Inside the tank, there should be a white plastic baffle that the pump will sit down into. This special plastic keeps fuel around the pump. Make sure that the locating dowels and retainers are tight and that it hasn't broken loose from the inside of the tank. If it's loose in there, but the locating dowels are still there, some appropriate push on retainers need to be replaced. Loose baffles were a problem with the '87 fuel injected Suburbans, which generated the necessary rust resistant flat washers and push on retainers to keep the baffle anchored.<P>Keeping the tank at least 1/4 full is a good orientation. The pump can generate a little heat and the fuel around it does serve as a heat sink, but that heat is less than the flash point of the fuel. The GM pumps are pretty durable at low fuel levels, but they will go away if they run too long with no fuel pumping through them.<P>When a customer comes in with a pretty new car with a fuel pump problem (i.e., died on the road or extended crank time), they will usually admit to running out of gas recently. If they come back again in about 10,000 miles or so with the same issue, it was probably due to a lack of fuel issue again.<P>Always put a new inline fuel filter with a new pump. The failed pump could have put some trash in the lines (which might be partially clogging the old filter).<P>Prior to pulling the tank down, put a meter on the fuel rail and check the fuel pressure. It should come up immediately when the pump is powered up. If, during crank mode, it starts low and builds to the minimum pressure for the engine to run, it's a pump issue. Doing these diagnostics prior to pulling the tank down might be advisable as you'll then know where things are.<P>When those LeSabres were new, there were some fuel pump noise issues that were addressed with a couple of service bulletins. Usually, a "pulsator" or "damper" was put inline on the pump output side just before the pressure line joined the tubing in the sending unit. I don't recall the pulsators ever causing a problem, but at this point in time it could be a possibility. Seems like they were later added in regular production or some other change was made so they weren't needed.<P>My recommendation would be to run the pressure checks and see where things are. Then, put a new fuel filter on an see if things change (pressure or fuel pump noise). You might also backflush the filter to see what might have been in it. Plus, check the voltage at the connector to the fuel tank sending unit to see if it's where it needs to be.<P>For some reasons, the new "reformulated" fuel can clog the inline filters. Therefore, we recommend filter changes at about 30,000 miles (even though there might not be a recommendation in the owner's manual for such).<P>One other word of caution . . . have the tank as near empty as you can before you drop it down from the bottom of the car. Gas weighs about 6 lbs per gallon by itself, not counting the tank and sending unit. It would also be advisable to have the car on a lift with a transmission-style jack to support the tank as you lower it.<P>It might also be possible to access the sending unit/pump by removing an access panel in the floorpan (in the trunk area, under the mat). Some of the later ones are this way and it makes things much easier.<P>Perhaps it would cost more, but I believe that if you have the fuel pump replaced at a Buick or GM dealer, the pump will carry a limited lifetime replacement warranty as long as you own the car. If they install it, I believe it's "parts and labor" but if it's an over the counter sale, it's for parts only. That's the most expensive way to do that deal, but with proper documentation, it should be the last time you have to pay for that repair . . . I'd recommend you check out that option!<P>Plus, if there are some other issues causing the failures (vehicle-related), they'd probably find them too, plus having the diagnostic tools to check the necessary things too.<P>Back then, we had many more problems with the mass air flow sensors than we did with fuel pumps. The car would die out or start running poorly, all of a sudden, but if you tapped on the sensor, it could run fine again. Another reason to have good diagnostics for the problem as you can chunk lots of parts at these newer vehicles and not fix anything.<P>Other things to check for would include the oil pressure sending unit (which tells the ECM to power up the fuel pump when oil pressure is present outside of the crank mode). There might also be a fuel pump relay in the circuit. Have you checked the fuel pump fuse?<P>Thanks for reading through this with me.<P>Just some thoughts . . .<BR>NTX5467<p>[ 06-27-2002: Message edited by: NTX5467 ]

Hopefully, you put some camshaft lube on the lobes of the camshaft to help the lifters break in, even if it was the existing cam. Also, it's advisable to "prelube" the lifters (in a pan of oil to compress their plungers to force the air out of them) before they go in the motor. Then prior to start up, using an electric drill motor to prime the oil pump and put pressurized oil into the various galleys and passageways in the block. If, per chance, some air got trapped in the lifter galleys, it could well take a while go get out. Some engines are more critical on that than others.<P>For example, it used to be a problem to have noisy lifters just after an oil change on 454 Chevies (early '70s time frame). The fix was to use front galley plugs for the lifter galleys with a .040" hole in them to let the air escape when the engine was restarted.<P>Has someone put a manual oil pressure gauge in the engine to see where the oil pressure actually is or isn't? You can temporarily screw it into the same hole as the oil pressure sending unit goes (possibly having to short across the sending unit so the electric fuel pump might run).<P>All of these items are pretty generic recommendations. Knowing which engine it is might provide some more specific recommendations.<P>Just some thoughts . . .<BR>NTX5467

In the earlier times, at least in the world of BowTies, the starter main housing could be either "long" or "regular". The "long" one was due to more windings and a resultant higher torque capacity unit for bigger motors and such. It's been the prefered unit, as a result until the later gear drive starters came online.<P>Also, the aluminum end housing was shaped to clear the particular bell housing of the transmission attached to the engine. There were probably a dozen or so end housings for Chevrolets alone! Now, they've finally configured the end housing to fit everything.<P>The architecture of your end housing is what spaces the starter out from the flywheel plus clears the bell housing area of the transmission correctly. Two end housings can look similar, even with the same bolt hole pattern, and still have different build heights (which determine how the starter drive gear meshes with the flywheel). Typically, at least on later Chevy motors, the different diameter flywheels required different starter end housings, but usually of different bolt patterns (i.e., straight or offset). Similarly, there are starter shims available for these Chevy starters to correctly space the end housing so the starter drive meshes correctly with the flywheel ring gear.<P>According to a Chevy service manual I found a while back, with the starter drive gear "engaged", there should be about .040" clearance between the deepest part of the ring gear and the deepest penetration of the starter drive gear. It might be that you need to space the starter out from the flywheel before you get a new flywheel and have similar issues again. The starter might also turn faster without having to fight the flywheel quite so much.<P>When you go to the auto supply or dealer to get a reman starter, you always have the option of taking the core back later instead of handing it over at the point of first sale. This way, you can take the "new" starter home and swap the end housings before you install it. It might also be a good idea to put a new drive end bushing in (and lube it too) your existing end housing too. End result, you will have a starter with new guts working in conjunction with your drive end housing of known quantity and architecture/clearances. Then, when you're done, take the core back for core credit -- if you don't keep it to be rebuilt by a known good rebuilder later on. <P>In prior times, it was nothing to put new brushes and bushings in the starter, dress the armature, change the solenoid, and put it back on the car. Not too hard to do either! Those parts are still around, but aren't as common as they used to be as the orientation now is to do exchanges instead of repairs. After all, all you're doing is replacing the worn parts and everything else should be good as it was working beforehand. But times have changed . . .<P>I don't know how many starter drive end housing variations there might be for Buicks engines, but suspect there are less than the multitude for earlier Chevrolets. I would trust an AC-Delco reman starter to have the correct end housing more than I would from some other rebuilder/reman facility where they dump everything in a vat and such. Even so, a friend that used to have a large repair shop said he never used the starter end housing on the replacement starter (even the preferred AC-Delco units), he always swapped them out with the existing starter that came on the car--greatly reduced the problems later, which came out of his pocket.<P>I suspect you can find a replacement flywheel from the auto supply sources or transmission shops at a decent price. Just make sure it matches the old one in all respects.<P>I don't know what sort of time frame transpired between the time you purchased the reman starter and your request to retreive your old one, but the retreival should have been a doable deal as I rather doubt they ship the cores out daily or even weekly. The only thing would have been to firmly know which one was yours. In one respect, if you paid the core charge, they should have given you the chance to find the one you thought was yours (provided you knew which one it was), but most don't desire to deal with that. I do know that many of the main auto supplies put tracking stickers on the core boxes so they know what they are and where they came from (and how many might "get lost" somewhere). <P>Many auto supplies and all GM dealers require the core be returned in the box the new part came in or there is no core credit issued as they can't get their money if the part is not boxed.<P>Just some thoughts . . .<BR>NTX5467

One neat thing about the GM800 power steering gearbox is the large variety of gear ratios available for them. From slower "straight" ratios, to fast (2 turns lock to lock) "straight" ratios, to the variable ratios of the later 1960s. You might find some reman facility that can put the faster ratio in your gear box. Adding a smaller factory steering wheel can help the overall effect too.<P>Adding the sway bars and upgraded shocks should help a bunch. I haven't used KYBs yet, but got hooked on KONIs a good while back and like their combination of ride and handling, plus the adjustability factor. It sounds like you're headed in the right direction, though.<P>NTX5467

Eibach (made in Eibach, Germany) springs are a quality product. They are more high performance oriented and will typically lower the ride height about an inch or so. They are typically progressive in their windings (some coils are closer together than others) for a smooth ride that stiffens up with greater deflection. They typically are a major buzz word brand just as Baer Brakes and Flowmaster Mufflers, which can be good and bad.<P>To me, the main issue would be the lowered ride height -- and what that will do to ground clearance with the chassis and exhaust system (including the rear of the pipes!). What might look "cool" or "kewl" could not be easy to live with in real life if you have to compromise where and how you drive just for "the look". I'd rather have suspension travel so the springs and shocks can do their things as designed (without bottoming out), yet upgrade shocks and sway bars instead of changing springs, unless they are sagged and need to be changed, but I'd find some factory replacements for the upgrade suspension package, probably.<P>There are some advantages with lowered ride height and the similar lowering of the vehicle's center of gravity, but upgrading the sway bars and shocks can accomplish pretty much the same thing with less expense and effort--unless you're going to be in some road race class racing activities where an altered ride height is acceptable and needed.<P>Just some thoughts . . .<BR>NTX5467

Chevrolet has used some push in rubber plugs instead of screw in caps for their oil "add" holes in valve covers. Seems like the first ones were in the early '70s on the small blocks and they have been updated (in graphics and such) over the years. I don't know if that will match the hole diameter you need for your Buick motor though. <P>Seems like the more current applications would be the G-vans which need an extension from the valve cover to the front of the engine so you can add oil with the hood up.<P>The rubber stopper deal sounds interesting, but there might be different rubber compounds that would react differently with engine heat and exposure to engine oil.<P>Just some thoughts . . .<BR>NTX5467

There is a "grease" that GM has been using in production for quite some time. Many of the replacement sockets are packed with it in them. Many of the bulbs that are removed (for whatever reason) within a few years of production (in recent history) typically have it. It appears to be a thick, lithium-type grease that is yellowish/brownish in color.<P>I initially suspected it had something to do with corrosion resistance (as we usually saw it on rear sockets and bulbs) but later determined that it could well be there to aid in heat transfer to the socket and its mounting area. This way, the heat the bulb produces is spread more evenly instead of being concentrated with the locating pins and contacts. As the mounting areas and sockets become lighter in weight and construction, the heat transfer issue could be more of an issue than in the past when sockets and such were more substantial.<P>For some reason, we're not seeing it being used as much now as it was in the '80s and '90s. I have seen the "bulb lube" at the store, but I suspect it's more along the lines of the thick, dielectric silicone that goes inside the spark plug boots. <P>You can also use the dielectric silicone to coat anything rubber that might squeak (i.e., hood bumpers, weatherstrip) in addition to its original spark plug wire uses. It's thick-bodied, opaquely clear, and a little bit goes a long way. Motorcraft was one of the first sellers in the later 1970s and others now sell it in smaller amounts.<P>Whatever "goo" you found could be something that someone read about in some "tips" or something. Might not hurt to clean the socket out and "relube" it?<P>Enjoy!<BR>NTX5467

Correct, there is NO difference in the 5.7L LT1 enigne that came in the Roadmaster, Cadillac, or Chevrolet Impala SS. Same camshaft, same heads, same compression ratio, same dual exhuast, same horsepower.<P>The main difference was in the chassis components, as the Roadmaster did not have rear disc brakes. Also, what gave the Impala SS it's higher top speed was the lack of a top speed fuel shutoff in the computer plus the fact that torque converter would also stay locked up at WOT (just as Corvettes and Z28s did, as they also had speed V or higher speed rated tires).<BR>If you notice how the left hand exhaust lead pipe is shaped coming from the left hand exhaust manifold, that particular LT1 engine application now uses a PF52 oil filter instead of the "normal" PF35 or PF 1218 AC oil filter. To accomplish this deal, there is an alloy mounting "plug" that goes into the block as the earlier filter mounting "adapter" did, except it rotates the filter toward the side of the engine block for greater exhaust pipe clearance and is configured for the smaller diameter PF52 filter. This neat little item could well come in handy in street rod applications of any Chevy small block engine. If vertical clearance is also an issue, the shorter PF47 could be substituted for the PF52.<P>All of the chassis sway bars and springs would bolt right into a Roadmaster and Cadillac as they do on the Impala SS--sedan models only. Same with the rear disc brake setup.<P>The performance chassis setup on the Roadmaster was the "trailer package". Same components as the upgrade suspension on the regular Caprice, but not the same items as the SS had.<P>Enjoy!<BR>NTX5467

Steve's got some good recommendations. <P>Another thing would be to get some gear marking compound (still available from GM) to check the actual pattern on the ring gear. Those procedures are covered in most any factory service manual and can be performed without any special equipment (other than a brush to apply the compound).<P>Basically, I concur that if it's not making any noises or whines or clunks, a fluid change might be all it needs.<P>Usually, a 171,000 or 271,000 mile car will have other tell tale signs of the higher mileage.<P>Enjoy!<BR>NTX5467

It could be "old" rubber that has become brittle and will not handle the stretch anymore. Consider, most of those mounts were probably made many years ago and have been sitting in some warehouse since then, maybe not the same type of aging as if they'd been on a car, but they still aren't very new either.<P>You can probably find some mounts made with polyurethane, which might be a better alternative than solid mounts, but still not a good alternative to me.<P>If you can find some of the factory fix restraint kits (like they had for the Chevies back then) or get something of that nature made, it would be a better alternative. If you're pulling the rubber mounts apart, instead of the rubber breaking it will transfer those stresses to the exterior of the engine block casting. Many dirt track motors running solid side mounts tend to break the block in that area for just that reason.<P>The more solidity there are in the engine mountings, the more vibration will also be transfered to the chassis and car body. This is a main reason I'd stay with rubber mounts and put the restraint cables on them.<P>What would be the possibilities of upgrading the mounts to the later models that had internal travel limiters in them? Or even modify the mountings to use the upgraded Chevy mounts? I suspect these might be the best choices in the long run, plus getting a mount that is regularly available with fresher rubber in it.<P>NTX5467

I believe the 3.42 was the "performance" ratio for the Riviera during that time frame. I think that'd be as far as I'd go as the 3.73 and 3.90 (moreso) would put high cruise rpm higher than what would be comfortable and reasonably economical. You could get 3.91 and lower gears in the Skylarks back then, but those particular models did not have highway crusing as a priority, obviously.<P>Enjoy!<BR>NTX5467

I suspect there might be a circuit breaker in that circuit that could be kicking out with excessive electrical draws. The GM window motors are usually pretty reliable on those earlier vehicles, but the linkage could need some new lubricant on the tracks and slides inside the door or might be binding for some reason. The motors have no user-serviceable parts from GM and are sealed.<P>There also might be some plastic retainer clips which keep the glass straight in the run channel as the window goes up and down. If they come apart, it can let the glass cock and would put more strain on the motor. Usually, there's one at the top corner and on the front "short side" corner. You might not know they are there, but they are usually hidden from plain sight.<P>I think I'd pop the door trim panels off and put some fresh lube on the tracks and slides, plus check for the glass retainers I mentioned. That might be all that's needed and is certainly cheaper than new window motors.<P>With the door panels off, if you've got a good electic meter, you might make sure you've got full battery voltage to the motors. If not, you can trace the wiring to the door switches and such until you get the full battery voltage. Might be a high resistance in the simple contact switches too. <P>These are the main things I can think of that might be common between the two vehicles.<P>NTX5467

I don't fully understand your terminology "shorting the battery". <P>If you are having a situation where the battery is continually running down (i.e., loosing charge), there is a reason for that but it will possibly take someone different than a regular mechanic to find it. It could be something as simple as a chime module that is internally bleeding voltage to ground over a period of time, a dome light switch with chaffed wiring insulation, or it could be a problem inside the Electronic Control Module for the engine that is bleeding voltage to ground. Most general mechanics are not equipped to check for these things nor probably desire to take the time as it can be very time consuming.<P>Find an electrical shop or a GM dealership that has the sensitive electrical equipment to check for "parasitic draw" on the battery. Their equipment will record the minute voltages that are still working after the engine is shut off and the car is left sitting there. In this case, it could well be a larger voltage draw.<P>Does the vehicle have an aftermarket alarm system? Many times, faulty installations can cause havoc with otherwise good vehicles and their electrical systems.<P>If it takes like two weeks for the battery to go down, it's probably something small. If it takes like a day or two, it could be something like a dome light that is staying on.<P>While you're having electrical system tests run, also make sure to get a full charging system test done. Using the better equipment that a GM dealer should have doesn't take very long, but can be more accurate than what a private shop or auto supply might have in many cases.<P>Also, be advised that a dead or very weak battery can also cause the alternator to prematurely fail--especially on the newer vehicles--but not necessarily on your more vintage vehicle. Make sure that the cooling holes on the rear of the alternator are not blocked or obstructed with heater hoses or such. Blocking those cooling holes will cause the internal voltage regulator to overheat and the alternator will not produce the amps and volts it normally would, running the battery down as the vehicle runs as the engine will be running strictly off of battery power. In some cases, there is a plastic duct that should be attached to the back of the alternator to assist the cooling, but I don't recall your particular vehicle having one. As the alternator's been changed recently, it might be good to check this normally overlooked detail.<P>Usually, when a battery "shorts", it means that the plates inside the battery are touching each other and "internally shorting out". This is an internal failure mode for the battery itself, but such failures are very rare these days in cars. That's why I question your terminology here as opposed to "something causing the battery to run down."<P>Hope this helps . . .<BR>NTX5467

Sounds like there might have been some negotiations to settle the suits and only pay a percentage of the individual claims (dollar wise). Might have also been some "depreciation" issues just as the insurance adjuster depreciates the value of the 5 year old roof when they figure how much they are going to pay against a new one.<P>If you are so moved, I would think there should be a payment schedule that members of the class action should be able to get and/or should have been furnished prior to the settlement. As long as you empower a third party (who's working on a percentage deal anyway) to handle the negotiations, you sometimes have to live with the results whether you like them or not.<P>In some cases, it seems like a "bluff" of sorts as how much will you spend on litigation to get the other $680.00 (approximate) that you weren't paid.<P>Just some thoughts . . .<BR>NTX5467

The Great Race 2002 started this morning, the 15th. You can check out the race route this year on the Great Race website (www.greatrace.com I believe) plus a list of entrants, their cars, and sponsors. A LOT of Fords and I counted 12 Buicks out of 128 entrants. Of particular interest might be what appears to be the entries of Coker Tire with 3 1937 Buicks.<P>The website also lists the route and where events will be held along the route.<P>Check it out . . .<BR>NTX5467

The original magazine articles I saw on the original Dow-Corning silicone brake fluid sounded very promising--expecially in the parts of the world where temperature extremes were common (which would cause moisture to form int he system from condensation that would not be cooked out with use). At that time, they stated that you could mix it with conventional fluids and it would work ok, but if the vehicle did not see use for a while, the two fluids would separate out, yet still work. This was in the later 1970s.<P>A friend then acquired a '79 Corvette and we'd all heard about the massive costs to rebuild those 4 piston caliper Corvette brake systems (due to moisture issues, typically). He decided to change the Corvette over to silicone fluid as it was a DOT5 fluid. Local auto supplies did not carry it and he finally found some at the motorcycle shops (even in various brands).<P>He bought enough fluid and completely bled the system on the Corvette. He did notice a slightly spongier pedal for about a week and then it got very firm and consistent (must have been a little air that finally made its way to the top with time and use). No problems with the brakes at all, as I recall.<P>At that time, silicone brake fluid was in the same somewhat exotic orientation as synthetic motor oil, mainly due to cost issues and the fact that you had to get outside of the normal supply chain to find it.<P>I believe the theory behind silicone fluid is good, but only for systems that are reasonably new and well maintained.<P>Using a high quality brake fluid of the highest DOT spec number is a very good investment, from a closed container hopefully, but remember how the gallons of brake fluid at the old service station were always open? <P>Considering the higher level of performance of current brake fluids (compared to earlier versions), to me the reality is that unless you are in a situation where you need the extra performance of silicone fluid (not related to maintenance issues), the current DOT 4 fluid will work just fine and be compatible with all of the seals and such in the system.<P>Just some thoughts . . .<BR>NTX5467

I somewhat doubt it'll hurt anything. Plus, there should be a magnet in the pan to catch metal particles in the fluid as the fluid circulates and that magnet would hopefully attract the dipstick part.<P>The older Turbo400 and some of the Turbo350 dipsticks used to be prone to breakage near the end, but they were made differently down there and did not have the series of bends that later ones do. Instead of putting the dipstick in at an angle, try to get it pretty much inserted more vertically before you fully insert it in the tube. That might be difficult with the hood interference, but it will also keep that end from bending so much.<P>NTX5467

There is also a tool (that's been around probably as long as there have been flywheels) to use to rotate flywheels while still attached to the crank. It hooks onto the flywheel ring gear and probably will have better leverage to turn the flywheel than a wrench would. Works on all flywheels too.<P>It is a doable deal, as mentioned, but things are close in there. If there are any star lock or other lock washers under the heads of the crankshaft bolts -- which have a particular torque they need to be tightened back to -- be sure to put new ones in with the new flywheel.<P>NTX5467

Each year of those touch screen units has its own, unique, GM part number. Meaning, that for whatever reason, all three years are specific to the particular year of vehicle. I would have figured they would have been the same, but that was not the case when I researched it after the last Flint BCA meet.<P>That touch screen deal was a very neat, high tech idea and also allowed for a whole lot of diagnostics to be done from the screen. But, even back then they were expensive, with a dealer cost of over $2500.00 back then. I don't know if they were discontinued because of safety issues or cost issues, but they were neat while they lasted.<P>NTX5467

On some of the other GM vehicles which use the cabin air filters, they are placed on the passenger side, outside in the cowl area, beneath the windshield. They are accessible from outside the car, but you have to remove the plastic trim near the windshield wipers. A much easier job than the Park Avenues and Venture Vans (where they are hidden up behind the glove compartment).<P>Seems like there used to be some mileage recommendation, but that would vary depending on the area the vehile is operated in, with sandier areas needing maintenance earlier than other areas.<P>Enjoy!<BR>NTX5467

After reading the post a while back on retrofitting Dexcool coolant into earlier vehicles and also reading the commentary by Patrick Bedard in the July, 2002 "Car and Driver" magazine, I did some research on the web tonight and determined that such a <BR>conversion might not be advised in some situations as there are some important side issues.<P>Key issue -- Dexcool was designed for new vehicles which never had any green antifreeze in them at all. This could also include an older vehicle with a freshly overhauled motor, new radiator, and a new heater core, but the issue of lead solder in the system might be another issue too.<P>The year that Dexcool was first put in new GM cars at the factory, it was used universally in all of their cars and trucks in North America except for the Pontiac LeMans (built in Korea). A Buick rep came by the dealership to advise the sales people and others about the "new for that year" features on new Buicks. I had a chance to discuss Dexcool with him between meetings.<P>That first year, GM had exclusive marketing rights to sell Dexcool (even though it was produced by Texaco or jointly developed with GM, whichever is the case I don't recall now) and then Texaco could sell it the next year. After that first year, others could sell the Dexcool formulation too.<P>Dexcool chemically coats the entire cooling system during the first 3000 miles of use. This is an anti-corrosion coating and allows the solution to be completely silicate free. If, in an "emergency" situation, some non-Dexcool coolant is added to the system, in order to maintain the 100,000 or 150,000 mile change interval, the system and the contaminated coolant should be completely flushed as soon as possible and returned to the specified 50/50 mix of Dexcool and water.<P>Side issue -- by that time, all GM radiators and heater cores had no solder in them, using gaskets to seal the tanks to the cores.<P>I found a Saab brochure on antifreeze back in the 1980s. BASF was the manufacturer of their coolant and the publication mentioned that ethylene glycol and lead solder were natural enemies. When the additive package that kept the coolant from eating the solder went away, problems were not far behind. Hence, the necessary drain interval in systems with lead solder and the use of corrosion inhibitor additives back then. Therefore, with lead solder not in the modern cooling systems, that problem went away. Dexcool is an ethylene glycol coolant just the previous green coolant is.<P>With Dexcool having such a long service life, the amount of hazardous materials that would enter the enviroment from coolant changes would be lessened greatly. Plus, it went along with the GM initiative for basically no maintenance for 100,000 miles (other than oil and filter changes).<P>All of these things were begun back when Texaco was 100% Texaco and not a part of big oil that got bigger in recent years. At that time, their website addressed the retrofit issue. It stated that "green antifreeze" systems should be flushed twice to get all of the existing coolant out of the system, then the 50/50 mix of Dexcool/water could be added--but that the coolant would not have a service life of more than 50,000 miles. Why? because there would be enough residual "green" stuff in the system (that had soaked into the metals and such plus the previous additives in there too) to make it a contaminated system. I did find tonight, after I finally found the updated Texaco site on Dexcool, that up to 10% contamination of the Dexcool mixture with green coolant would be acceptable, but would nullify the long term (100,000 or 150,000 miles) protection of the system.<P>Now, in the first few years, some service issues with Dexcool generated some GM service bulletins, plus a few during the past few years too. These bulletins were concerned with specific vehicles too.<P>The worst one was with the 4.3L Chevy V-6 in S-10 vehicles. The bulletin specified that if an accumulation was found on the filler neck of the radiator, to clean it, inspect the radiator neck, and replace the cap with a newer cap. Now, this is where it might be of concern to older vehicles . . . Dexcool reacts with air to form a grainy textured accumulation. What was happening in the S-10s, the cap allowed the coolant level to drop resulting with the radiator not being completely full all of the time. It eventually resulted in the system not pressurizing and more coolant boiling out with more accumulation in the process--as the unpressurized coolant would boil at close to 220 degrees F, which is just past the 195 degree thermostat openning temperature. Yet the pressurized system would be fine to just past 260 degrees. The additional recommendation I came across was to maintain the coolant recovery jug to the "Full Hot" level with a cold engine, with the added coolant ensuring there would be no air in the system.<P>Key thing here, older systems with no coolant recovery jug mechanism would basically be operating as the "low coolant" systems in the S-10, even with a good radiator cap. Therefore, the grainy accumulation could very well form and proliferate in the earlier radiators. Therefore, the implied message for older vehicles would be to install a large capacity coolant recovery system and keep it full.<P>As for the much ballyhooed water pump life issue? Even in the old days of high silicate coolants, water pumps usually lasted about 50,000+ miles anyway. I somewhat doubt that even the most die hard BDE member would drive their vintage cars that far over a 3 year time frame, but I could be wrong. Since the retrofitted Dexcool coolant is only rated for 50,000 miles anyway, it sounds like more expense to use Dexcool and not get any better performance/durability of the coolant and other components.<P>Also, you'd think that water pump sales would have gone away, but we still put them on light trucks under factory warranty even now, but on vehicles where obviously there is some lack of maintenance. With other vehicles, they did basically "dry up". No doubt, Texaco and GM did document added life from Dexcool in that respect--and it makes sense too--but I just don't see that that would be an issue with an older, retrofitted system. Others might differ on that and I respect that.<P>Other than the "Car and Driver" commentary I mentioned earlier, I found a website with a good commentary by John Bruner, a retired GM engineer, on some of the problems with Dexcool systems on new vehicles and what was determined to be the cause. The address for that page is: <A HREF="http://www.imcool.com/articles/antifreeze-coolant/dexcool-johnbruner.htm" TARGET=_blank>www.imcool.com/articles/antifreeze-coolant/dexcool-johnbruner.htm</A> <P>Another revelation from Mr. Bruner's article, the coolant seal tabs that used to be put in all GM cooling systems at the factory are not used with Dexcool. <P>I recommend that Mr. Bruner's article be read and understand how it would relate to a system that does not have, was not designed for, or has a poorly maintained factory coolant recovery system.<P>I found another website that discusses conversion from green coolant to Dexcool. That page is: //autorepair.about.com/library/weekly/aa052601a.htm<P><BR>Finally, the Texaco Dexcool information bulletin is at: //thegenesisnetwork.equilon.com/genesis/prodinfopdf/HAVOLINE . . <BR>That's one long address and you can find it at the #19 search result when you go into Yahoo and put "dexcool" in the search window. Anyway, it's the current information sheet.<P>I also went into the Zerez antifreeze site and looked at the things mentioned by Mr. Bedard. The items he mentioned are there plus some other product information and factory service spec numbers.<P>In the course of these things, I also ended up in the <A HREF="http://www.imcool.com" TARGET=_blank>www.imcool.com</A> site. One of the many cooling system items from their BBS mentioned voltage "in the coolant". Using a digital VOM, place one probe in the liquid coolant and the other on a good ground or negative batter cable. If the value is .2V-.5V, the coolant is still good; .5V-.7V, borderline; greater than .7V is bad. I knew that modern computerized sensor motors had to have good coolant in them for the sensors to function correctly, and this pretty much defines the ranges. The voltages are also related to alkalinity and related things. With the sensors working on small voltage ranges and the coolant being an electrical ground condutor too, it's all related to a certain extent.<P>I recommend that everyone check out these websites and magazine articles and make your own decisions.<P>Thanks for reading through this, I know it's a little long but there is a lot of information to consider and cover. If, by chance the webpage addreses didn't "make the trip" here, email me direct and I'll send them to you.<P>Thanks!<BR>NTX5467

I concur, some tachs just don't interface well with electronic ignitions, whether it's correct idle speed readings or other things. On the electronic systems, the dwell is in the control module (as I understand it). Yet, for a V-8, your reported readings do sound a little high . . . does your dwell tach automatically sense 4, 6, or 8 cylinders?<P>Enjoy!<BR>NTX5467

With all of the ignition items apparently new and sorted out, my suspicion is that it's the accelerator pump in the carb not functioning for some reason. Hopefully, as Pete Phillips previous driveability issue with his '58, you don't have a wire in the distributor bleeding off voltage that would otherwise go to fire the ignition.<P>I also suspect you have set the idle speed and mixture as they should be (max vacuum at the specified rpm in Park) as that can sometimes affect off-idle response.<P>I would contact the people who rebuilt your carb and see if they reused the existing leather accelerator pump item or replaced it with the more modern rubberized version of the pump cup. Might even be a blocked fuel circuit to the pump discharge nozzles or wear in the pump cavity.<P>Also, the accelerator pump linkage needs to be functioning in the first place and adjusted to specs (which it should have been before it was rebuilt anyway).<P>Just some thoughts . . .<BR>NTX5467

I suspect a trans upgrade will be in order as the Chevy 3-speeds were not very reliable even behind the Chevy motors. As the Chevy has rear leaf springs, the driveshaft issue should be easy to deal with. On the Chevy light trucks back then, they used a closed drive shaft whereas the GMC's had an open driveshaft. Only differences were in the end housing on the 4-speed trans and what happened on the rear axle. Having leaf springs back there (instead of coils) simplifies things.<P>The steering gearboxes and columns were bolted to the frame. Might modernize that with a more modern gear box and a flex coupling with a later steering column. A friend put a '70 Monte Carlo column in his '55 Nomad, "shaved" the lock cylinder off of it, put the '55 steering wheel on it, and it looked great. The color codes on the wiring even matched up. If done covertly enough, many people probably would not know the difference.<P>Don't forget about the front springs too . . .<P>Enjoy!<BR>NTX5467