Carbueretor Gasket Question

[Guest shadetree77]

Well, looks like I have some collateral damage from that pancake syrup colored gas that i was unknowingly running through my recently purchased 52 Special and now I have to rebuild the carburetor.:mad: I'm starting to think I'll never get her on the road before the Georgia Mountain Moonshine Cruise-In!! Anyway, it's a Carter WCD 2-barrel carb. I took the carb off the manifold and I got online to order some new mounting gaskets. When I looked it up on the CARS site two kinds of gaskets come up for my carb. I have posted pics below. Problem is, my carb doesn't have the metal looking silver one it just has the thicker black one called a "carburetor insulator". As a matter of fact, it has TWO of those. One is stuck to the the manifold and the other is stuck to the bottom of the carb. Anybody know if this is correct? Is it supposed to have one of each kind or is it supposed to have two "insulators"? If anybody could tell me how many of each kind I'm supposed to have and the correct order to install them it would be much appreciated as I really want to make it to that show in August! It'll be my first one. Thanks again.

Edited July 2, 2011 by shadetree77 (see edit history)

[Aaron65]

I'd just get the thickest one that will work with your carb studs and run 1. I'm running a 7/16" ish one from Bob's Automobilia.

[Pete Phillips]

The purpose is to insulate the bottom of the carburetor from the heat of the engine, in addition to providing an air-tight seal. With today's lousy fuel, you need all the insulation you can get, to keep from having vapor lock.

Pete Phillips, BCA #7338

[Mark Shaw]

A common practice is to use sealant on one side of a gasket (usually the corroded side) to ensure a good seal where there was once a leak. I suggest you leave both spacers in place and put a standard gasket between them.

[NTX5467]

One point to consider when running "gasket stacks" is IF both of the thicker gaskets have the metal tubing insert in the carb stud holes to ensure that the gasket is compressed "just so much" and no more. Otherwise, as with the carb insulators from Mr. Gasket (where a soft base gasket is alternated with an aluminum plate), it's too easy to try to get things tightened down securely AND unevenly, which can crack the base plate of the carb.

The thicker gasket would, I suspect, be the OEM gasket. The thinner one would be an aftermarket version, which can also work well, but the thicker one is more desireable for its insulation properties.

Depending upon which of the two gaskets (on the manifold or the carb) is better, I'd get out the Mr. Gasket gasket scraper and start removing the more deteriorated one. Or I might remove both of them, dress the mounting surfaces gently, spread a thin film of high-heat black silicone sealer on both sides of the new thick gasket (makes removal easier and easier to clean up for later needs), and gently torque the mounting nute.

Running two of the thick gaskets (with the metal inserts I mentioned) can effectively increase the plenum volume of the intake manifold. This can help higher rpm performance a little.

From experience with thinner base gaskets (from carb kits and such), they also result in the carb being too close to the bottom of the intake manifold's plenum area, which can adversely affect performance and tuning. In the first case, I had to re-snug the mounting nuts every week or so. In the second case, performance was "flat", but made a huge increase with the thicker OEM gasket in place.

Just some thoughts . . .

NTX5467