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Hello Everyone,

I'm working on replacing the gaskets on a MC101A/A and a BDC-14 carburetor and was hoping to get a little pro advice. I've taken everything apart and cleaned the mounting surfaces and the carburetor thouroghly. I read recently about prepping the gaskets by applying or soaking them with WD-40 or oil or maybe even electronics grease in order to help prevent leaks. The thread also discussed applying a very thin coat of gasket sealer to the stuffer and manifold gaskets for added leak protection. I thought I bookmarked the thread but unfortunately I didn't, and now I cannot find it here or in the archives of the old forum. 
My questions to those with experience are, what type of oil is best to use on the gaskets; mixed two cycle fuel, straight two cycle oil, Marvel Mystery Oil or some kind of electronics or silicone grease? Also, what type of gasket sealer, if any, should I use on the manifold and stuffer gaskets? Most of the new gaskets are Fel-Pro type and some of the carb gaskets are of the black, pliable felt/paper type. Lastly, I have all new gaskets except for the circuit plate gaskets; is it ok to reuse these and if so should I prep them in any way?

Thanks in advance to anyone and everyone that can offer any tips and/or advice...
For all internal carb gaskets, I use WD-40 Just spray some on and wipe it around with your fingers. It works well on carb diaphragms, too (light coat). For head gasket and exhaust header gasket, nothing. For all other engine gaskets, I use spray K&W Copper Coat or the NAPA equivalent. Wait ten to fifteen minutes after spraying before installing gasket and tightening screws. A gasket sealed with K&W will peel off pretty easily, and spray brake/carb cleaner removes the residue. You may certainly reuse the internal carb gaskets and diaphragms, but I always replace the cork fuel inlet gasket as they seem to harden and shrink. I also replace the adjustment needle O-rings periodically. WD-40 these before CAREFULLY sliding them onto the needle to avoid damage to the O-ring on the threads. I have yet to have an engine fail pressure test using these methods. A lot of guys have good luck oiling gaskets with a light film of engine oil. Ted
Ted, much appreciated....thank you.

I'm glad you mentioned the adjustment needle O-rings. Upon disassembly of the carb, I noticed what my manual referred to as the O-ring washers were missing. I presume these are tiny metal washers that are situated between the adjustment needle springs and the rubber O-rings, or is that incorrect? If they are not, are they of a different material?? I don't have another Mac carb to reference, so without them there, I'm not sure what they actually look like.

Thanks again for taking the time to share your expertise ...
Vince, the Tillies certainly have a small washer between spring and O-ring, and I'm sure the Mac carb does too. It keeps the spring from eating the O-ring. EC Distributors has the washers. I bought a bunch of them as I'm always dropping one. They seem always to end up in the expansion joint of the shop floor. Ted
Ted, I know what you mean...when I drop things on the floor they seem to fall through a crack in the time-space continuum and never reappear again! In this instance, they were never in there. I appreciate the lead on EC Distributors, I'll order the washer and O-rings too if they have them.

Regards,
Vince
EC doesn't have Mac carb parts. For flatback carb stuff, try Vince Hughes and Paul Booth. For Walbro BDC parts, try Terry Ives Industries or send Steve O'Hara a PM. EC is mostly Tillotson. Ted