oil and fuel additives

[chub chub]

hey, i have a question about oil and fuel additives. my 52 special straight 8 makes a hard rapping noise associated with lifters (so does my 63 chevy straight 6 and my friends 58 ford straight 6).i've read that this can also be caused by carbon buildup in the cylinders. there are a lot of products that claim to reduce these problems. some say oil additives are a waste since the ingredients are already added to most oils. some say oil and fuel additives which contain detergents are bad because they free up junk which gets lodged in other parts of the engine. what are the general feelings about adding these products to 40-50 year old engines. do they help or cause more problems down the line?

thanks,

chub chub

[Guest]

don't slop up your engine, you need to adjust your "valve lash" with a feeler gauge.

take off the valuve cover, warm the car up, lower the idle to as slow as you can get without it dieing, and adjust the tappets as stated in the owner manual.

Noise is good, to tight and you will burn up the valves. intake and exhaust have diffent cleareances, check the book.

don't look for easy answers in a can!

[NTX5467]

I concur with doing a valve adjustment. That's gotten to be a "lost art" in some respects.

In reality, the best way I've found to decarbon an engine is to drive it on a trip long enough to need a new tank of fuel to return from, plus maybe a can of fuel detergent or even a small can of Berryman's B-12 in the first tank of fuel. Chevron Techron is good for that too. There are many "almost instant" fixes for the carbon situation in late model vehicles, but I sometimes wonder about them in an older engine.

In prior times (like the early 1970s), everytime I made a 500 mile round trip in the car (a Buick-level car) I took to college (which had about 80,000 miles on it then), after each trip it seemed to run just a little better. Everything was tuned and adjusted to specs so it was not running bad for any reason. Only thing I could think of was getting the residual carbon deposits in the combustion chambers cooked out a little more each time. The carbon we have with modern fuels is a different breed, it seems, than what we had with the "real" fuels of the earlier times. If you read the literature on how many more cleaners and such are in modern fuels, you'd think everything in there would be spotless, but that doesn't seem to happen. Afterall, the carbon usually tended to accumulate in the "dead flow" areas of the combustion chamber. If it got too bad, it'd up the octane requirements of the engine.

Modern design combustion chambers have more "active flow" area so they stay pretty clean anyway. To pass emissions, they have to but what clogs up is usually the EGR circuits--especially if the injectors "dribble" too much and/or lower quality, price marketed fuel is used.

Oil additives come in two types--emulsifier additives and viscosity increaser additives. If an engine has seen reasonably decent maintenance with high quality oils over its life, it should not be "caked up" inside with sludge, but there can be some accumulation in certain areas where there is less oil flowing over them (i.e., lifter valley in a V-8, valve train in the cylinder head). The emulsifier additive (like the StewartWarner Alemite CD-2 Oil Detergent I used in the later '70s on used cars I bought) will dissolve the soft deposits it flows over and put that stuff back into suspension in the motor oil so it'll be washed out with the next oil/filter change. This happens over the course of hundreds of miles of use and not "immediately".

The thicker additives, like STP and similar additives, will usually thicken the oil and raise the viscosity number by "10". They might have some extreme pressure additives in the formulation too, but the main thing is the viscosity improver additive that makes it thick. If these additives do raise your engine's oil pressure, then it probably needs an overhaul/rebuild anyway. If you just put some heavier oil in it, it might be cheaper and work just as well.

When you run the valves, you'll need to have the engine fully at operating temperature. Therefore, get it out and drive it at least 30 minutes in one stretch. Then, bring it in and get the oil changed while it's still hot. With fresh oil/filter in place, then drive it some more and bring it in for the valve adjustment while things are still hot. Don't forget to have the appropriate gaskets ready when you do the valve adjustment too!

Also, an old Motor Manual mentioned that lifter noise can also be due to valve stem/guide clearance being on the high end of the clearance spec. If, with the engine running, the manual mentioned, you can take a shop towel and push on the valve spring with the engine at low idle, and the noise goes away, it's most likely a guide clearance issue.

Solid lifters have their own particular valve train noise, even when cold. Having a little lifter noise from adjustments that are a "hair" on the loose side is fine. At least they don't do the VW routine where they tighten up with use (which makes for all of thost wheezing VW engines we used to hear).

Seems like those old Ford 6 cylinders had a spring loaded tip on the rocker arm that was supposed to make them quieter than other solid lifter engines. That would require a different technique to get the adjustment correct on also.

Remember too, "set the intake clearance just as the exhaust valve starts to open" and vice versa. This guarantees that the valve being adjusted is on the base circle/no lift area of the particular cylinder's cam lobe and not on the edge of the "ramp" which preceeds the lift segment of the lobe.

Enjoy!

NTX5467

[chub chub]

i haven't gotten to adjusting the lash on the buick yet. i did it on my 63 chevy last weekend along with other adjustments. it is running better but still has the hard rapping noise. i am trying to get it running as well as possible so i can sell it for buick money. it also has a history of carbon fouling plugs. i just want to be able to sell it knowing i did all i could to make it as reliable as is possible. then i can concentrate on chub chub. any other suggestions are welcome.

thanks

chub chub

[Reatta Man]

I agree completely about making sure your engine is totally adjusted and in tune before expecting any additive to fix a problem.

The absolute best fuel additive for cleaning carbon deposits off of valves and the tops of pistons is BG 44K. It is not normally available to the public, but is used extensively by professional repair shops.

If you are military and have a base near you or know someone who can, it is available through some, not all, military exchange gas stations for about $14 per can. If not, you can order it through www.cambridgeauto.com, and click on RYNO Products on that Web site. On that site, it will cost you about $20 per can plus shipping.

You can also go to www.bgfindashop.com and type in your ZIP code to find a shop near you that sells it.

This stuff is a super-concentrated cleaner, similar to Techron, only in greater quantity (about a pint per can, I think) and more concentrated. By the way, if you have a Ford 4.6 V-8, those engines are horrible about coking up the intake valves, especially cylinders 5, 7, 6 and 8. This stuff works miracles on those engines.

I've recommended it several times in this forum, and don't know if anyone has used it. I suspect not, because if anyone had used it, they would be back on this forum telling everyone how well it works.

As for oil additives, BG makes a product called MOA, or Motor Oil Additive. It is a cleaner for the crankcase. I haven't used it, but have heard others recommend it.

For older engines, I use the older engine treatement that comes in a tall silver can, but I can't remember what it is called. The stuff is a thick blue liquid. There are different sizes for 4, 6 and 8 cylinder engines. I have an 84 Olds 98 with a 307 gas V-8, 80,000 miles, never had any engine work done, and I use it in that engine. All I can say is the engine uses no oil between change intervals of 3500-4000 miles, so that tells me it works. I get 16 MPG in the summer running the A/C and have gotten 19 in the winter with no air running.

I don't like viscosity modifiers because in extreme heat, some of them tend to sludge up in the crevaces and corners of the engine. And contrary to what some people still believe, always use detergent oils unless you know for a certainty that your engine can NOT use it. I know some people still demand non-detergent oils because I was at a shop one day recently and heard an old guy insist they put Quaker State straight 30 weight non-detergent in a 2002 Dodge truck with the 5.9 V-8. He WILL be rebuilding that engine between 60,000 and 90,000 miles and will then complain about Dodge making lousy engines. If I were the shop manager, I would have refused to put non-detergent oil in a late model engine because of potential lawsuits, but that is another discussion.

Cheers,

Joe

[Guest imported_JPIndusi]

Reatta Man:

I found a Toyota Dealer near me that deals in BG products. I bought two cans of the BG 44K. The parts man says that they add a can to every Toyota serviced every 15K miles. He says it is very concentrated. I put a can in my 1996 Lincoln Towncar which has the 4.6 V-8. I'll let you know my experience with it.

The oil additive you refer to is called RESTORE. Some mechanics say it helps, others around here like Lucas oil additive.

Joe

[NTX5467]

The oil additive I have seen with the name "RESTORE" is a totally different thing than a detergent-based additive. It's the "wonder drug" for worn engines, not a cleaner-upper as such, that (so they claim) fills in the score marks on the cylinder walls and makes them all shiney again and raises compression readings. Kind of like the old "MotoNew" of the 1970s that went in the fuel. Could you possibly have meant "RISLONE" instead? Remember those old advertisements for CaSite Motor Honey?

BG does make some good products and many shops that use the driveability-related chemicals also have some of the other ones too. BG485 is a good battery terminal/acid cleaner, for example.

Just some thoughts . . .

NTX5467

[Reatta Man]

NTX,

Yes, RESTORE is the oil additive I was thinking of. The detergent stuff is a BG product named MOA, for Motor Oil Additive.

Didn't mean to be confusing; the Restore does work with SLIGTLY worn older engines, in other words, pretty near normal wear due to aging. I don't think it or anything else can restore an engine due to poor maintenance. At best, any product used in the oil to help coat a piston wall can only be a fraction of a micron thick; anything more is going to be too thick and be washed away or pushed into the combustion chamber and burned during the ignition stroke.

Joe