Hello to you all. I have recently resurrected an old 145 that was sitting in a barn since 1992 and after a few road tests the engine has developed a strange noise. It is a knock, but doesn't seem to be related to ignition. It seems to go away as the revs go up. The valves are quite noisy too. I have been all over with a stethoscope. Alternator, water pump, engine block at each cylinder, oil pan, bellhousing etc. Can't seem to hear the source of it. Seems to be coming mostly from the manifold side so I am wondering if perhaps it might be something to do with the exhaust, or the mounting bracket, or the manifold itself. The engine mounts are old and soft, so maybe something is just clanging against something else. I am at a loss, but I know there are a lot of experienced people out there so I have mede a video and maybe someone somewhere has an idea. Honestly, at this stage, any ideas would be helpful, as I am all out.
Here it is, let me know what you think.
https://vimeo.com/614528025
Warren