Name that motor sound.......

[plug ugly]

Motor is a 94 351 with 160K or so on it.

This only happens once the motor has been running for a while around town. It starts at idle or decel, and at first, if I blip the throttle, I can get it to go away for a moment. Then once its been screaching for a bit, it wont go away at all. Its only noticeable when RPM's are lower. Not sure if its due to other noises, or it just plain stops. Warm Oil pressure is at like 15 to 20 at idle, but builds to 35 to 40 running. I believe it is coming from around the crank somewhere, but its hard to tell

[ThrillHouse]

Re: Name that motor sound.......

damn that doesn't sound good, the belt tensioner maybe? sounds like it's close to the front? possibly a spun bearing but hopefully I'm wrong

[crawlin68]

Re: Name that motor sound.......

That is a very strange sound. Sounds like a dry bearing about to go. Do you have an automotive stethoscope that you can start putting on various components to see if you can pinpoint it's origin?

[Henry66]

Re: Name that motor sound.......

Since one guess is as good as another... I think it sounds bell like and is outside the motor. Like maybe something behind a pulley.

[plug ugly]

Re: Name that motor sound.......

Since one guess is as good as another... I think it sounds bell like and is outside the motor. Like maybe something behind a pulley.

did that a few weeks ago, and the sound was still there, but fairly faint. It was kind of weird. Maybe a bearing going out, and transmitting through a/the bells? I try and get audio tomorrow.

[plug ugly]

Re: Name that motor sound.......

pulled the belt, and the noise is still there. Using a stethascope, it appears to be loudest around the crank pulley.

Its a little hard to hear, but you can hear it.



oh yeah, getting some white smoke at start up too. Just replaced some exhaust pieces, but it should have burned of by now. Thing is running good though.

[pipelayer]

Re: Name that motor sound.......

White smoke should be water. Could it be the water pump? Are you loosing water at all? Have you pressure tested the cooling sistem?

[ThrillHouse]

Re: Name that motor sound.......

could be the water pump, how old is the front main seal?

[plug ugly]

Re: Name that motor sound.......

would the water pump make a sound if the belt was pulled?

[pipelayer]

Re: Name that motor sound.......

Not sure but I wouldent think so unless its a vibration thing.

[plug ugly]

Re: Name that motor sound.......

how old is the front main seal?

original

[plug ugly]

Re: Name that motor sound.......

got it all back together and went for a drive today after replacing the front crank seal. Additionally, I threw a different dizzy on, and swapped out a suspect tensioner pulley.

The noise persists. Its slightly' different, but not by much. The edges of the belt do look like they are being warn down some, but the noise really sounds like its coming from the crank area.

Oil pressure is fairly normal for the tired motor. Its fairly consistent too, low at idle, 35 to 45 at rpms. So is it not a main?

Any ideas on what to check next?

[pipelayer]

Re: Name that motor sound.......

Turn up the radio and drive it, if something is wrong it will find you.

[Cococnty66]

Re: Name that motor sound.......

I would take all belts off and run it if the noise is gone its ether a pully or alternator / PS/water pump that will narrow it down don't run it long though

[Cococnty66]

Re: Name that motor sound.......

would the water pump make a sound if the belt was pulled?

The pump won't make noise with the belt off