Re: Cortes121's 1955 Clipper Custom

Posted by HH56 On 2020/11/27 15:14:30

I think while the mechanical pump works, the lever actuator arm and spring appear to have gas residue and it reeks of gas. The oil smelled of gas as well -

I suspect the diaphragm in the old pump has deteriorated and is letting fuel enter the crankcase. In addition to a possible tear or other mechanical damage, the old diaphragms and coatings are not compatible with ethanol and many modern fuel additives. Even if the pump was known to be good, if it has an old diaphragm from the days before ethanol they generally have a very short life after being exposed to modern fuel.