My old 86 dodge 150PU has a slight knocking at a certian RPM. I know it is the risk pin or main knocking. But really how long can you drive like this? When you hear it knock you can give it a little throttle and it seems to go away until you get back at a certain RPM. I guess it has something to do with pressure build up?
This is not an everyday driver but just an old pickup to have around when needed. i know I need to replace the manifolds and I have already put a new carb on it. It actually runs pretty good exept for the knocking.

If I was you, I would first try to change higher viscosity engine oil, for example 15W-50, in case you don't have tried it already. I have found that it prevents some noices in worn-out engines. Maybe that will help you till you rapair it.

Jukka

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Mopari on parasta mitä rahalla saa - Mopar is best you get with money