Carb Questions......

[jm]

My 1963 Johnson 40HP enging can not idle at low RPM without stalling. It runs great at high RPM. I purchased the engine used and from it's appearance I doubt if any work has been done on it besides the water pump I just replace. The top of the plastic engine casing had a good deal of dried up foam which had fallen over the years and was most likely sucked into the carberator. Does anyone have instruction for removal, rebuild, and installation? Any other ideas would as to what could cause this would be great.<br /><br />Also yesterday I was stuck out in Lake Monroe with a drained battery. The battery is brand new! What should I do to trouble shoot this?

 

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Re: Carb Questions......

That foam in the cowling is sound proofing.<br />It is very possable that the stuff got sucked-into the intake. However, if this DID happen, the carb is not going to suffer ill effects, but the reeds might.<br />Take a can of ValvTect Marine decarb Cleaner, and use as directed on the can. This should desolve any foam material on or in the reeds,and the rest of the engine.<br />It will also do a fair job of removing carbon.<br /><br />This foam liner should be completely removed. I wouldn't replace it iether, unless it is just too noisey. The stuff is all but useless. They make a great sound barrier material,that can be cut and shaped to fit, and does not desintigrate like the foam.One such product is called "Thermoplex". It is very expensive,but very rugged,and virtually fireproof (A definate plus). It also is impervious to petroleum,and it stays put.<br />Again, I don't think this will effect the carb. If this engine sat for over 5 months,and the fuel is old,you may have carb problems due to the varnish it drank,but the foam pieces wouldn't be part of the fuel delivery,only after it has been delivered.