Me and my beautiful 1956 Buick

[EmTee]

Drive on!  (with an extra quart in the trunk, just in case...) 

[Beemon]

Don't worry, I've got three currently... lol

[dmfconsult]

15 hours ago, Beemon said:

 

the local parts guys here were scratching their head over this because apparently no one has ever asked.

I had a similar experience when taking my old coolant to the central recycler here... they didn't want to take the coolant I placed in the distilled water container.  He said it has to be in the container it had come from.  I explained to him that you mixed coolant and distilled water 50/50, and so it would be impossible for me to bring it back in only the coolant container as I had no way of separating it.  He finally agreed to take it, most likely due to the fact the water container was clear so you could easily tell what was inside!

Edited September 19, 2017 by dmfconsult (see edit history)

[NC-car-guy]

Wow!  I've never heard of such troubles.   Here in NC any "convenience site" as they are called, takes trash, recyclables, oil, coolants, and batteries.  Then a few take paint, tires, electronics, and appliances in each county.  Our local auto store chains also take oil and coolant.

[JohnD1956]

16 hours ago, Beemon said:

kinda unrelated, but I got some looks yesterday because the road draft tube was venting at idle. I'm avoiding a compression check because I don't want to disappoint myself!

 

Leave it alone.  Make it big first, then the rest of this will be easy.

[Beemon]

10 hours ago, dmfconsult said:

I had a similar experience when taking my old coolant to the central recycler here... they didn't want to take the coolant I placed in the distilled water container.  He said it has to be in the container it had come from.  I explained to him that you mixed coolant and distilled water 50/50, and so it would be impossible for me to bring it back in only the coolant container as I had no way of separating it.  He finally agreed to take it, most likely due to the fact the water container was clear so you could easily tell what was inside!

It is my firm believe that every amateur hobbyist should have a chemical distillery in their garage. Fortunately back home, we had a once-a-week waste disposal place that was within 10 miles. Not so much the case out here.

 

9 hours ago, wndsofchng06 said:

Wow!  I've never heard of such troubles.   Here in NC any "convenience site" as they are called, takes trash, recyclables, oil, coolants, and batteries.  Then a few take paint, tires, electronics, and appliances in each county.  Our local auto store chains also take oil and coolant.

Back in the urban environment of greater Seattle, we had many places that took just about anything. Now I'm in a small town out in the Washington wasteland where we have one O'Reilly's, one NAPA and one ma and pa auto store. I think there's only one repair shop in town, too, but I didn't bother stopping in to ask them, because they're on the other side of town. Most likely: "drain it down the toilet".

[KongaMan]

Autozone will take anything around here.  I just did a oil change, transmission flush, and differential flush and dumped the old fluids into various oil antifreeze and milk jugs.  They took them all without question.  I would've taken taken some old, open brake fluid as well but I forgot to throw it in the crate.

 

We used to have an 5-gallon bucket that we dumped old fluids in.  When it got full, we'd pour it on the brush pile and burn it all.  Those were different days.

[Beemon]

Today I linked up with the local student car club. Needless to say, I'm the oldest car by at least 40 years.

 

 

And here's that super beetle:

 

(There was someone taking vanity photos :P)

 

It's what you'd expect, Hondas, Toyotas, Subarus, Mistubishis... Overall, it was a nice cruise. We went from a store in town over to Cheney, which is a smaller town between rolling hills and met with others for lunch. We then went down to Spokane to meet up with another group. There, I met a father/son duo who were working on a 74 Super Beetle. They put in a 1904 with dual carbs and dyno'd it at 95HP, which is probably pretty good for a Volkswagen? Anyways, we got to talking about old cars and it came down to the subject of the future of classic cars. Kids today just aren't interested in carrying the flag, and everyone who knows the ins and outs of the hobby are either dying, dead, or sitting on wealth and only sharing with you if you pay a hefty price. Unfortunate, but probably true. A couple guys at the meet made comments like "I'm glad I don't have to deal with a carb", even though they've never touched one in their life. All in all, a short 200 mile round trip. The WCFB is performing as it should. If the gas gauge is any indication (and accurate, of course), then I'm at 1/8 tank with 223 on the odometer. Usually at just about E, there's about 3 gallons left in the tank, so I'm looking at about 14.9MPG.

 

On an unrelated note, the green suburban in the picture above has this really wicked sound system in it. I was talking to the owner about it, he's got two car batteries and three alternators running the show there. I ordered some Packard 440 wire for the Buick, so I told him to enjoy it while it lasts.

Edited September 25, 2017 by Beemon (see edit history)

[JohnD1956]

I'm glad the Buick is holding up for you. But I am sorry to hear the report on the potential future for classic vehicles. Sounds like this small subset of the age group has next to zero interest in anything older than they are.  In a way it represents the same values I myself followed.  At their age i did not want a car from the 30's or 40's . i wanted one from the late 60's cause that was what i really remembered growing up.  Also it had to run and be inexpensive.  I only got into the 56 cause the neighbor gave one to me. 

If this attitude persists today then might as well drive what I have to my own end, and forget about restoration alltogether.

[Beemon]

 

Goodbye carbon-core wires. I don't want to be that guy where I say "Wow, after changing them the car runs better!" But really, it does. What I don't get is that the OEM rotor is 10,000 ohms of resistance, but spark plugs are made for 5,000 ohms of resistance... why not make the rotors 5,000 ohms of resistance, too, to keep in line with OEM specs? The other alternative would be to find 10kohm park plugs and a resistor free rotor from a 50s Chevrolet. This is why we can't have nice things.

[Bloo]

Nothing is ever simple......

 

Still, It isn't that critical. I always ran resistor wires on cars of that vintage. Not the carbon ones, but the silicone/carbon type (accel, etc.. and most modern resistor wires). Resistance was added for radio noise suppression. In years past, the rule of thumb on cars with points ignition was to run either resistor wires or resistor plugs but not both. I guess now that non-resistor plugs are getting so hard to find, maybe it is time to give copper wire another look.

 

On a points ignition, the design-limiting factor for spark energy is the points. You can only ask them to carry so much current for so much time before the life gets really short. There is only so much time to charge the coil before it needs to fire again. The more cylinders you have, the worse it gets.

 

When the ignition fires, the voltage rises until a spark initiates. Instantly, the voltage goes WAY down, as the voltage needed to maintain a spark is much less than what is needed to initiate one. The spark will continue until the coil is discharged enough that it can no longer maintain this lower voltage. More resistance raises these voltages a little. More gap raises them a lot. You can see all of this on an ignition scope.

 

The lower you can make these voltages, the longer you can keep the spark going. Some companies, mostly European ones, (Bosch, Marelli, etc.), liked to run real narrow plug gaps, like maybe .021 or .025 because they felt the long duration spark was most important. I don't agree with this. I find that nearly everything with points will run better and be less susceptible to fouling at about .035 . This is assuming that the coil and the insulation in the system can support the higher voltage.

 

Under acceleration, the voltages go up because the higher cylinder pressure makes it harder to initiate and maintain a spark. At high rpm, the coil has less time to charge. The coil has to have enough headroom to keep firing under any conditions. If you raise the gap very much, you will probably bump into the limit (and run out of spark) on a points ignition.

 

Some guys put "40,000 volt" or "50,000 volt" coils on thinking they are raising the voltage. They aren't. The spark plug gap, (and to a much lesser extent the wire resistance, rotor resistance, carbon button, etc) sets the voltage. A higher voltage coil increases the headroom, probably at the expense of points life.

 

On a points ignition car, if you can run .035 and the spark never goes out under high rpm or high load, you are good. It really doesn't get any better.

 

Many years ago, one of the hot rodding magazines, probably Popular Hot Rodding, ran some tests with plug gaps on a dyno. They found modest increases in horsepower up to about .050, and measurable though insignificant increases up to .060 . After that, the law of diminishing returns kicked in. This probably had a lot to do with minimizing the burn time variations in 1980s unleaded fuel that had octane boosting chemicals floating around in it at levels around 10% (much like today). In the 50s, with Tetraethyl Lead I suspect they would have found less difference.

 

Another limiting factor is insulation. On many cars, the weakest spot is the bit of plastic or bakelite between the contact on the center of the rotor and the grounded metal below. If it burns through, the car could stop running. It usually doesn't. It usually keeps running and slowly trashes the advance mechanism. It will look like a combination of wear and rust has nearly cut the pins off.

 

Most electronic ignition cars can do .045 no problem. It is a great place to be. Some are specified lower or higher. At .060 it is tough to keep the insulation good. You have to have really good wire insulation, boots, rotor, cap, etc. You cant have wires in metal looms or anything like that. Spark tries to get out everywhere. You can probably get this to hold together until the next 30,000 mile tune up (on an electronic ignition car). Any higher than .060 and it is impossible. GM released some cars that ran at .080 . They could blast through the insulation somewhere or another in about 2 weeks. In the field we set those at .057 and let them burn open to .060. They last a while that way. .045 is a much better place to be. That same HEI ignition used on the .080 cars ran 50000-60000 miles with no maintenance at all at .045 on other cars.

 

 

 

 

Edited September 28, 2017 by Bloo
.. (see edit history)

[Beemon]

Thanks for the explanation, Bloo. I had done some research on solid core wires before making the purchase. A lot of arguments against solid core point to the additive resistance of the cap/rotor, wires and plugs creating a larger spark to overcome the resistance, which is fine as you pointed out for electronic ignition systems. When I first started driving the car, I had used suppression wires and AC Delco R43S plugs. They're rated for 6-15kOhms, which is a very large range. When I replaced them with Champion plugs, rated at 5kOhms, it ran much better. I now run NGK 5858s, also rated at 5kOhms. As you said, the points are the weak 'point' of the system and if the charge cannot overcome that resistance, then you have a significantly weaker spark.

 

Maybe if I get really bored, I'll pull my plugs and heat them with a butane torch to release the loctite on the terminal end. All you have to do is unscrew the terminal and pull the carbon resistor out and substitute with a solid copper core wire... but that's a lot of work and a lot of risk. Is $2/plug really worth it? Might be easier to empirically figure how much to remove of the resistor on the rotor to achieve that 5kOhm resistance to bring the system back from 15-16kOhm to 10kOhm, as the Buick engineers in 1956 intended.

 

Also I wanted to note that the radio works perfectly fine in the car after the addition of solid core wires. Other people's radios? Eh... Also through my research, I found that solid core wires generate RFI range in the 2.4GHz range, which is where wifis and bluetooths live. Essentially, everything inside the car would be protected by the chassis ground acting as a Faraday cage. I often wonder what it was like to live in a period where you knew who was driving down your street based on the sine waves displayed on your TV.

 

Speaking of radio, I replaced all of my vintage capacitors today with ignition capacitors (that's all that's available) at the .18-.2MFD range. I know the coil capacitor and generator capacitor is supposed to be within .3MFD (the wire was pulling and fraying out the front of the can) and the voltage regulator is supposed to be .5MFD (it had leakdown issues). I would like to at some point open up one of these cans by removing the plastic cap on the end and shoving a modern electrolytic capacitor in there of equal value. Anything is better than nothing, and I was only getting slight popping before (leaky and faulty capacitors). Now it's crystal clear.

Edited September 28, 2017 by Beemon (see edit history)

[Bloo]

Then its fine. You have resistor plugs. In theory you don't need resistor wires. It sounds like you have it well sorted.

 

A few ohms too much or too little isn't going to make a discernible difference. If you eliminate all the resistance, it will just make noise. Thats why the carbon wires came about. They weren't reliable, but the modern silicone stuff is fine.

 

The gap is what makes the difference. The resistance of the gap is WAY higher than the additive resistance of the plugs, rotor, etc. The total resistance is what determines how high the voltage spikes before it fires. The gap swamps everything else.

 

If you exceed what the system can do, the spark doesn't get weak, it just plain goes out. This is really obvious when you have one open spark plug wire. It might run ok under light load, but accelerate hard and that cylinder will drop, because the voltage does not rise high enough to overcome both the gap and the open wire. The voltage rises as high as it can go, and the spark never happens

Edited September 28, 2017 by Bloo (see edit history)

[Bloo]

 

Here is a trace for one cylinder. Thats time on the x axis, and kilovolts on the y. You can see it took about 14 kilovolts to initiate the spark, and less than 2 kilovolts to maintain it.  Graph only goes to 21 kilovolts. Thats probably a little more than a typical 12v car with points can do. It has some headroom. Tightening the gap will give it more headroom (by lowering that spike), opening it will give it less. Want to know what it can do? Pull a wire off with the scope connected. That spike will rise to its maximum. The only caveat is the maximum falls off with RPM.

[Beemon]

Thanks for the graph, really puts into perspective how much resistance can hurt an ignition system. If your headroom is 21kV and you need 22kV to fire at high RPM, you're going to stall under load. Exaggeration of course, but probably a reality with 6-15kOhm plugs, 1000Ohm/ft wires and a 10kOhm resistor rotor. Also kind of explains why dual point systems work, because they can open longer to maintain a positive spark. Funny you mention checking by pulling wires... was doing my "okay this one is arcing..." go to grab the coil wire and almost fell over! lol. With the addition of these wires, I've picked up throttle response and a slight lean bog is pretty much gone. I didn't bother measuring the resistance of my old wires, but they would probably yield some interesting results. They're from Pertronix, and just like everything else made by Pertronix, they left me disappointed (at least they didn't leave me stranded).

 

By the way, for anyone interested (and wish I had seen these earlier):

.5MFD voltage regulator capacitor

.3MFD generator capacitor

.3MFD coil capacitor

 

I guess the Chevy crowd is good for some things...

 

 

[Bloo]

Yeah, dual points increase the dwell, which increases the charge time, and allows the ignition to keep up at higher RPM than it could otherwise.

 

 I doubt you would be able to see 5k ohms difference... at all. The resistance of the gap is so unbelievably high, and it is in series. I really think you, or the scope, (or the car) would have a hard time seeing 5k.

 

Are you even sure this had copper wire when it was new? I just looked in the manual and they really dodge the issue. I'm pretty sure carbon wire was commonly available by 1956. If it had resistance wire, you are already at about the same total resistance.

 

If you have the plugs at .035 it can pull a steep hill under hard acceleration without cutting out, and it is not missing at high RPM, then it is as good as points ever get. Really. Remember the best thing an ignition could possibly do for you is light the mixture perfectly every time. If it doesn't miss, there is very little room for improvement.

 

The biggest disadvantage to points on a street engine is that they start degrading as soon as you drive the car. The rubbing block wears, retarding the timing, closing the gap, overheating the points, etc. This is where electronic shines. 20,000 or more miles later, the dwell and timing are still the same! You can wear out a set of plugs, and never even have to set the carburetor.

[Beemon]

I've personally had more luck with points than anything else. Curious to try the MSD, but that's an expensive venture and knowing me, I'll just take it back off and put the original distributor back in..

[Bloo]

MSD isn't a direction I would go. IMHO it makes troubleshooting difficult. They do work well.

 

If you really want to ditch the 5000 ohms....

How about these? (similar to the ac44 the book recommends, a step colder than what you have now)

https://www.ngk.com/product.aspx?zpid=10036

 

or these (one step colder yet, similar to the books ac42 "for commercial ot sustained high speed operation")

https://www.ngk.com/product.aspx?zpid=10037

 

Edited September 28, 2017 by Bloo
.. (see edit history)

[1956322]

I'm assuming you're talking about the msd distributor not the boxes.. I've been running their distributor for a few years..expansive yes.. Works well. Yes lol

[Beemon]

Where do you run your distributor at?

[1956322]

Boy I'd have to dig up where I set the springs and bushing at..I  think Spring wise it was set to the second to lightest springs and the bushing I think it has the largest bushing.. Now as to where my timing is set.. Well I'm not quite sure.. Everything matches up at tdc but if I set it to five degrees you can't even drive it.. So it's set at about 30 degrees which can't be actually 30 degrees but yet everything lines up at tdc.. All I know is it cranks fine and runs great lol

[Beemon]

I think I'll stick to what I know for now.

 

[1956322]

Dual point double the fun double the trouble lol

[Beemon]

Today I took the Buick up to Steptoe Butte, a good 30 minute drive from the University, with the local car club.

 

 

It's too bad about the sign, was thinking about dropping my steering box in the toilet...

[Beemon]

This last weekend I went to the first annual "Generations Collide" car show put on by the school's car club. At one point during the show, I was exhibiting the different stuff that was otherwise different on modern cars, and when I got to the choke heat stove flapper on the exhaust manifold... the thermostat spring was gone! Lol, I'm not sure exactly when and where it fell off, but I've been driving around with single exhaust for I don't know how long. I'm heading back home the weekend of Halloween, so I'll be doing a manifold swap. I also have an exhaust leak I can't seem to shake, so I'll be installing gaskets until I can have the manifolds planed. I've been told gaskets will crack the manifolds, but other makes and models ran cast iron manifolds for years with gaskets without problems... seems kind of like an old wives tale? The first year I had the car on the road I used the gaskets from the engine kit without issue, until I removed them because of some information I read on line. I understand the cast iron will flex and that being mated to the block restricts it from flexing vs a gasket surface.

[1956322]

I think the important thing about using the gaskets is don't keep retorqueing them 

[old-tank]

Best to use high temp RTV if surfaces are smooth.  If already leaking, use gaskets and don't look back.  The only negative on long term gasket use was rusting and pitting of the heads and manifolds under the gaskets, making it necessary to keep using.

[NC-car-guy]

Once you take em' off they never seem to go back exactly the same.  I've always put a gasket back after pulling the exhaust on any of my vehicles.  The key to not cracking the manifold is not over tightening.

[Beemon]

5 hours ago, 1956322 said:

I think the important thing about using the gaskets is don't keep retorqueing them 

 

Right, they might seem loose because the flexed under heat - you want them to return to their natural resting point when they cool and re-torquing them will cause them to bend and possibly crack.

 

5 hours ago, old-tank said:

Best to use high temp RTV if surfaces are smooth.  If already leaking, use gaskets and don't look back.  The only negative on long term gasket use was rusting and pitting of the heads and manifolds under the gaskets, making it necessary to keep using.

 

Yeah I had used RTV on the first engine, and when we took it apart, there were obvious black charring around the edges where it didn't quite make a positive seal. I didn't remove the manifolds on this engine when I got it, but it's coming from the passenger side and when I got the engine, these bolts were loose. I don't know if the RTV will solve this issue, but I'd rather just throw those gaskets on and be done with it. I don't know what the head surface looks like yet.

 

5 hours ago, wndsofchng06 said:

Once you take em' off they never seem to go back exactly the same.  I've always put a gasket back after pulling the exhaust on any of my vehicles.  The key to not cracking the manifold is not over tightening.

 

I think the issue with my first set was that they were off the block for 30 years. These ones don't seem to have been removed because they still have the French locks on them, but the bolts were loose on one side...

 

That's another thing. On my first block, I used bolts and lock washers. On this engine, it has the French locks. Does it really matter which way you go? I figure with the French locks, you can re-use them and torque down without having to worry about the bolts coming loose from vibration. Also, is it going to behave like an intake manifold gasket where I can get away without using sealer or should I use some high temp RTV with the gaskets? Thanks guys.

[NC-car-guy]

12 minutes ago, Beemon said:

 

That's another thing. On my first block, I used bolts and lock washers. On this engine, it has the French locks. Does it really matter which way you go? I figure with the French locks, you can re-use them and torque down without having to worry about the bolts coming loose from vibration. Also, is it going to behave like an intake manifold gasket where I can get away without using sealer or should I use some high temp RTV with the gaskets? Thanks guys.

No lockwashers.  Use the french locks.  If you torque down a lock washer, you're asking for it.  I've never used sealant on exhaust manifold gaskets or any gasket really unless the mating surface was too bad.

[Beemon]

Thanks Matt, I figured as much. Here's hoping I can re-use them... lol. Willie was right, I should have just ripped that flapper valve out when I had the chance. Maybe this will give me the excuse to put my single exhaust manifold on in place of the flapper manifold (if the pipe lines up).

[Beemon]

This weekend I made the decision to take the Buick home. Come November 1st, chains are required (if snow) to cross the pass, unless you have M(ud) + S(now) tires. The tires on the car are M+S SUV tires, but with one wheel and given the fact that sheet metal doesn't grow on trees (and not that I'm not confident in my driving skills, more worried about getting hit in the parking lot by someone else), I made the drive. For those of you that don't know, coming East from the West, it's a steep climb to the top and a long slope down the other side... but from the East side to the West, it is a long grade to the top and then the steep fall off on the other side of the pass. I had the heater on full blast with the driver window down going up, trying to keep the old girl from overheating. Granted, this is a virgin engine... I've decided to permanently park the car for now. There is a huge rear main seal now, where I lost 2 quarts to the half way mark home, and my steering wheel has 1/3 rotation of play in it... so bad I half turned the passenger tie rod out so the car would pull to the right so I had a point of reference on the steering wheel. Since it'll be sitting for a while, looks like for fun I'll be pulling the engine back out, and doing a bottom end seal/inspection like I should have done in the first place.  Haha. That aside, the car isn't coming back over the pass unless a new steering box is mounted in. I think I talk about this too much, but isn't it nice when you pay "professionals" to fix these things and they're still broken? Oh well... I'm looking into a rack and pinion type setup that I could use to replace the drag link. The only issue is you need new steering knuckles to change the turn radius of the wheel. Otherwise, a Jeep steering box will probably be the best bet since it has the same spline pattern as the pitman arm and looks pretty close to original.

This upgrade is prompting me to do other things, but mostly theoretical. Everytime I tell myself I'm going to keep it original, something always rears it's ugly head.. So I figure why not apply my schooling and "modernize" the car in the right way (IE not throwing Speedway junk in there). You might see my newest scheme in the modified boards.

[Bloo]

Regarding the steering box, If it were me, I would attempt to rebuild it. I would get 2 or 3 of them, as many as I could get my hands on, tear them down and see if I could come up with enough good parts for a serious rebuild.

 

Rack and pinion, in my opinion, is just an invitation to reliability problems, doubly so if it is power rack and pinion, and with no real advantage on a big heavy vehicle like that. (I love manual rack and pinion in smaller cars).

 

If you are set on putting something different in there, a Saginaw "variable ratio" box (made by GM in the late 70s) one of the best things ever made for a big heavy car. There was a car version and a truck version. The car version mounts on the inside of the frame rail, and the truck version mounts on the outside of the frame rail.

[Beemon]

I want to say my steering issue has something to do with the worm gear and probably bearing pre-load. The box is one year only, and I think it might be shared with Oldsmobile. All the boxes at the yard are like mine, with lots of play. I don't know if that's how they're supposed to be or not, but it seems like it. If anything, I would like something new and modern versus digging around for more old parts that may or may not work. And the car may be big, but it weighs the same as a modern full size car and they don't seem to have any issue - the big, heavy trope for classic cars seems to be widely misguided as a modern full size Buick is only 400lbs lighter than my 56 Century. It may seem like a lot, but it's only a 10% difference.

 

The problem with rebuilding is that, even if you find the right parts to make it whole, you're still on borrowed time. Honestly, the best bet would be to requisition the original blueprints from General Motors and have the internal guts remanufactured, which wouldn't be worth it unless you could do it yourself.

 

This is just unfortunately one of those things where in order to keep it original, you use worn out parts and hope for the best, like most everything else. Or adapt. Securing three or four boxes will run me upwards of $500 if the sellers are generous and shipping isn't involved, and even then I feel is an extremely low-balled bid. Versus ordering a new box from the parts store for  $150 and having a machine shop make a bracket for $100, then $20 in fittings, maybe new hoses, and a $30 rag joint coupler. You still come under, you have a box that was made in the last year so any shop can get the parts and rebuild if anything happens, and it can be serviced local. The opposite of any vintage box, which may or may not have to be sent to a specialist who has a monopoly on kits and aren't willing to sell them, then return the box to you after paying top dollar and it's still loose.

[old-tank]

I think you need the VickyBlue method:  http://forums.aaca.org/topic/285773-power-steering-fluid-leaking/

[BuickBob49]

I, too, was at WSU, two grad degrees in the 1980s and 90s.  A great place to build up your calf muscles.  You must be taking courses in Dana  and Sloan halls.

 

I had my 49 Super there for years, stored in garages, a pea combine warehouse, and a friend's barn with very nice owls who kept the mice at bay!  Rico's Smokehouse (now Rico's Pub since they banned indoor smoking) was a mainstay for many of us!

 

Does the city of Palouse still have Palouse Days with a car show in the fall? It used to be a lot of fun.

 

I understand that there is a new BCA chapter in Spokane.  Maybe a good place to look for Buick help.

 

When I was in Pullman, Held's Auto Electric on S. Grand Ave. was a great source of help with old cars.  They may no longer exist. Butch and Jerry ran the place in those days.

 

 

 

 

 

Edited November 9, 2017 by BuickBob49
Garbled text (see edit history)

[lancemb]

On 10/9/2017 at 12:58 PM, Beemon said:

I understand the cast iron will flex and that being mated to the block restricts it from flexing vs a gasket surface.

That's it exactly and why so many cracked with the factory no-gasket set up.

[Beemon]

Finals are next week and I just finished my last assignment for the semester so I had some time to tinker. As everyone knows, putting any type of modern carburetor is a surefire way to re-wire the starter system. I've come up with an idea, using stock 1/2" ID tubing and a 1/8" flange to make a pseudo carburetor starter switch.

 

 

Dimensions aren't final as I don't have the parts here, but the biggest obstacle would be overcoming the throttle arm. The original system had a machined flange on an extended throttle shaft that pushed the ball bearing into the switch. This system would require some extra throw to compensate for the lever arm, but otherwise would function the same. A pipe thread would be tapped into the vacuum relief section of the switch with a barbed fitting plumbed to manifold vacuum, so when the engine starts, it would suck the ball bearing into the relief chamber. With the ball bearing gone, there should be at least a 1/4" air gap between the switch and the piston. And of course, the ball bearing would have a positive metal-metal seal after the ball is set with a hammer in the end of the brass fitting. It would be pretty clunky apparatus sitting off the end of the carb, but you wouldn't have to put a lame push button in it's place.

[JohnD1956]

Nice tinkering.  Too bad a longer rod could not be attached to that particular linkage tang, and then the switch remotely located towards the rear.  Actually, given todays electronics, I have to wonder if there isn't an electrical solution rather than a mechanical, or a combo electrical/mechanical.  At any rate, don't forget to allow for adjustment to "time" the switch.

[Beemon]

To be mounted to the rear yippy would have to use the top most hole on the throttle arm so it would push backwards when the throttle is opened. That is a much longer arm and would require a much larger throw, but can definitely be doable. You just run the risk of interfering with the air cleaner or ignition coil since it would be above the carb and to the back.

 

I would much rather have the switch towards the back. Maybe fab up a z- rod like a manual clutch linkage and then mount it off the back tab? I feel like it would definitely interfere with the coil at that point, though.

 

As far as electrical switches goes, a meter that easures how far something is pushed in or out could be modified to work if such a switch.