Need some help identifying a strange vibration sound.

[Erik Jenkinson]

I have a sound like a vibration of a loose bolt etc. That only occurs in low rpm, just above idle, and stops at "cruising" speed. I think it may be coming from the injection pump. My reading tells me that injection pumps usually leak upon failure. Is this sound common to a failing ip? Or should I keep digging? I have throughly searched for anything obviously loose with no luck. My stethoscope is definitely leading me to believe it is the injection pump. Is this what a worn timing chain sounds like?

 

[porkysplace]

You might want to inspect the flexplate . Also check your harmonic balancer , they are known to go bad.

 

[antennaclimber]

Recently my M1009 was doing the same thing. At idle I could hear a noise and detect a slight vibration. Went away when I increased engine RPM.

Crawled under the front of the engine and found a missing nut on the power steering pump bracket.

Installed new nut and tightened all the mounting hardware and the problem was solved.

Karl

 

[91W350]

Check the bolt that secures the starter brace to the block. My 1008 had that particular tingy rattle....

 

[antennaclimber]

You might want to inspect the flexplate . Also check your harmonic balancer , they are known to go bad.

Good advice.

 

[Erik Jenkinson]

I tightened the power steering bracket, and my starter is good. The sound really seems to be coming from the ip. Is that common? No one here seems to complain of sound, just leaks. My truck runs good, maybe just a slighty lower rpm at start at best.

 

[wayne pick]

Go back and look at the power steering bracket. You may have tightend everything but the top tab will snap right at the angle. If you don't look at it closely, it's easy to miss. Also check behind the pump for the small bracket that connects to the engine. If it's missing, it can be the cause of a broken pump bracket. Ask me why I know this.

 

[twomorestrokes]

I had a loud vibrating noise at idle that would go away when I raised the engine speed. Bugged me for awhile. Turned out to be the air cleaner! Yt was tight but I felt silly.The fiber washer is worn away at the intake and tightening the wing nuts down very tight stopped the noise.

 

[Warthog]

The air cleaner is often overlooked. New gasket is available at your local parts house.

sometimes the throttle cable will rub and vibrate on the cleaner.

 

[tennmogger]

Helpful tools to pinpoint vibrations, rattles: 1) long shaft to put against the suspected component, then to the side of the head near the ear, Your skull is an amplifier! 2) Section of fuel line to the ear, carefully, and the sound will really be pinpointed.