Ford 3000 Gas engine vibration

[mbf]

Ford 3000 Gas engine vibrations- I have a great running Ford 3000 that has an engine vibration at certain rpms, but not constantly. Depressing the clutch makes no difference, and there are no strange noises. Can be felt through the entire tractor when it occurs, does not need to be moving. Occurs whether or not pto is engaged. Any ideas where to start looking? Thanks - MBF

 

[Texasmark]

I have and have had numerous Fords. The 4.2x4.2 3 cylinder diesels are/were smooth running machines. I have/have had 2ea. 4.4x4.2 that liked to vibrate above 1600 RPM. Both were low hour tractors. I looked into a vibration damper that may be the problem, but in the manuals, I could find no reference to a vibration damper on the crankshaft like some other engines have.

 

[DaveBN]

Do the vibration seem fast like crank shaft speed or slow like cam shaft speed? Maybe a bad fan or water pump. Can you run it briefly without the can belt on? Could be something more serious like a chunk of a piston skirt broken off and laying in the oil pan. How long has it been doing this?
Dave

 

[mbf]

I bought the tractor last year and noticed it after I replaced the shaft seal in the power steering pump. No noises at all, and it's definitely related to engine RPM, but doesn't occur all the time, only when the engine is spinning up under load. I was hoping to drop the oil pan and look at the vibration damper, but my manual and Messick's parts breakdown doesn't show its location or what gear it is driven off. I was hoping someone on here would have had a similar experience before I open it up. Thank you