SparkFireRun 1 #1 Posted September 3, 2017 Been focusing on the carb, but now I'm wondering if it's crank seals...New diaphragm, flap valve, little bit-o permatex... i did in fact officially give up. Gave it back. The old man noticed as the engine sputtered, that the exhaust was leaky. He said, "well, I'll put new gaskets on that". Well that got me to wondering, could that be a running problem ? I wouldn't have thought so, but.... Share this post Link to post Share on other sites
factory 487 #2 Posted September 4, 2017 It could be the crank seals leaking, as far as I know we haven't found a source for the original style ones, but they can be replaced with O-rings of the appropriate size (there are two different sizes of the crankshafts & bearings depending on the age of the engine). The first two engines I worked on ran OK with leaky exhaust collector gaskets (I had no replacements at the time), but I now replace them as they usually leak after removing the cylinder. I think I have at least one earlier engine that refuses to run properly despite being completely stripped and rebuilt. David 1 SparkFireRun reacted to this Share this post Link to post Share on other sites