Screeching noise from my engine - HELP!

jmoore16

New Member
Jun 1, 2004
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Riverview, MI
This post is also on the '94-'95 post but I thought there may be different folks reading....

Ok - Here is my story.

My wife's '94 347 convertible was running great until the end of last driving season (we live in Michigan) when her car developed a strange sound. Everything is great when the engine is cold but after about 5 minutes of driving and warming up, a screech develops from the front end accessories. I kind of sounds like a bearing in an alternator that is getting ready to seize up. I thought it was the alternator when I packed the car away because the screech would change in pitch at idle, and I could change the pitch with engine RPM.

I pulled her car out of storage a couple weeks ago to get it ready for the summer. I have a automotive stethoscope so I used it to find the screech. Alternator case? No. Power Steering pump? No. Water pump? No. I unhooked the fead belt and expected the noise to go away. Nope! Noise is still there so I think that I ruled out the alternator, water pump and power steering pump.

I searched the forums for similar problems and the closest thing I could find was the distributor. I put a new distributor in but unfortunately, the noise is still there.

Does anybody have any idea what this could be? Timing chain? Cam bearings? Rod or main bearings? What does a car sound like if it has spun a bearing? My oil pressure is good and the sound is not there when the car is cold.

I am at a loss. Thanks so much for your help.

John
 
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Never thought of the timing pointer...

I will go out and take a look.

Just wondering, why would the sound get worse when the engine is warm if the pointer is touching the damper? :shrug:

I will check and get back with you...
 
Damn. I can't think of anything else on the front of the motor. I'm just trying to throw some simple stuff out there. One time my buddy's car sounded like it had a bad lower end knock, and he just had a couple loose crank pulley bolts. Best of luck with the problem, I hope it's nothing serious.
 
Noise from around the intake and distributor...

I finally found with the stethoscope a noise that is unusual and similar to what I can hear from 20 feet away when the car is warm. I am getting the screeching noise from the forward most upper to lower intake bolt which is near the distributor.

Lifter???
 
Intake Leaks

Somebody told me an intake leak would sound like a teapot boiling (kinda like what I have here), but I tried starter fluid and didn't find any vacuum leaks. I tightened up everything but still, the noise is there.

I just don't know what to do. Anybody want a clean '94 convertible? :shrug:

John
 
I have heard the same thing with my 347. Obviously it is not the belt since you have removed it on your car. I have read that aftermarket distributors have to be ground down slightly on the botom to accomodate hardened oil pump drives. The oil pump drive is not cut down enough to accomodate the distrubutor when installed. I ground mine down and thought I had enough free play but now I am questioning it. You may want to check this. If your disributor goes in easy until the last couple thousands of an inch this may be the problem. IF you find something else, let me know.
 
Grinding down the distributor...

I have heard the same thing with my 347. Obviously it is not the belt since you have removed it on your car. I have read that aftermarket distributors have to be ground down slightly on the botom to accomodate hardened oil pump drives. The oil pump drive is not cut down enough to accomodate the distrubutor when installed. I ground mine down and thought I had enough free play but now I am questioning it. You may want to check this. If your disributor goes in easy until the last couple thousands of an inch this may be the problem. IF you find something else, let me know.

Best hint I have had in a while. I pulled the cam out on Saturday and the bearing is shot but I don't think that this is the reason for all the noise. Maybe a symptom?

I am using a stock 94-95 distributor (actually two as I thought this was the original problem) and a stock oil pump and driveshaft. I would think that it would all work. I am beginning to think that it si my oil pump going bad.

Any thoughts? :shrug: :shrug: :shrug:

John