Screaching sound

TedG

TedG

Member
First let me start by say thanks to all the Ford Barners that responded to my questions in the past, I don't think this project would have gotten this far this quickly without their help, the car was delivered to me as a rolling chassis and large pile of body parts in April of 2010.

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We finally got some nice weather so we got the Sport Coupe out to try and wrap up a few loose ends, the engine started right up and we quickly got the generator adjusted and were warming it up so we could retorque the head gasket, after running for about 4-5 minutes it started making a horrible screaching sound similar to the noise an alternator makes when charging at a high rate so we quickly shut it off.

Thinking it may be a bearing in the generator I removed the belt and restarted the engine, the noise was still there.

Also thought the throwout bearing may have been the problem so tried working the clutch pedal in and out but that made no change in the noise.

I loosened the lower end of the oil return pipe and oil runs out after the engine is cranked over for a short time so I'm pretty sure there's sufficient oil flow.

Since it does not sound like an internal engine noise and the only other engine related work I did was replacing the distributor shaft & bushings and (becasue the car owner insisted) converted it to electronic ignition, I pulled the distributor, it spins freely by hand with no noise.

If left to sit for 5 mins. or so and then restarting the engine at first there is no noise but after running for a short period the noise returns.

Anyone have any thoughts on what may be causing this?

As always any help would be greatly appreciated.
 
It might be a dry rope seal. Dribble some oil around the seal on the timing cover to see if that helps. That would be the best cause as it is easy to fix.

But, it could also be the cam thrust plunger. I've had this happen a few times with the springs available now, which are shorter than the originals. I some cases, the bore has worn so the plunger spins, screeching as it does. I had to have a few of the timing cover bores bushed and reamed to fit to get it to stop. Sometimes it also happens when the cam thrust face was not refaced, and the roughness catches the plunger and spins it. The sound is louder from the front of the engine. A stethoscope will help determine the location. Also, a pulley rubbing the engine mount can do this, check to see if there is a wear mark on the pulley.
 
W/pump? Remove the fan belt and try it. Use a cheap (h/freight) stephascope (sp?) w/fan belt off and try to find origination of the noise.
paul in CT
 
I'm betting on the cam shaft plunger in the bore of the cover. I had one once that was intermittent and the oil hole in the casting was plugged and the plunger was un lubricated. Put a stethoscope near the bump near the timing pin when the noise starts.
 
Great looking car, nice job!! i think it is the water pump, let us know how it works out.
I am in the Phila. if you need help.

mike
 
check the length of the 3 capscrews that hold the starter in place. With the engine running and screeching, loosen one bolt at a time. Also check the front motor mount, the pulley could be contacting the crossmember.
Rainmaker Ron
 
My first thought was a DRY DISTRIBUTOR, but since you put in a new shaft and bushings, I assume you had the clearance correct and had it well oiled, so now I think the cam pluger is the most likely. I installed and started an engine that someone else rebuilt, and it had the same intermittent screaching noise. I oiled the front seal and checked the front pulley, and both were fine. The noise came and went several times as I ran the car several times in 15 to 30 minute heat and cool cycles. The noise finally quit for good after about 6 hours of run time. I'm sure the rebuilder didn't put grease on the cam pluger, and it may have run dry for a while. Anyway, all is well with it now.
 
I know it's crazy, but how about something simple like a leaking manifold gasket ? You know, it might make a noise similar to blowing a blade of grass between a persons thumbs.
 
Sounds like the cam thrust plunger to me. I bet it had a repro one fitted. I had exactly the same problem. I fitted a good original plunger and spring and everything was quiet. Both the repro plunger and spring looked 100%. It goes to show, "there is nothing like good original parts."
 
Thanks for all the replies and the suggestions.

Paul & Mike, one of the first things I tried was removing the belt to eliminate the generator & water pump.

Ron, I did check for clearence near the pulley, crossmember & front motor mount and all looks good, also would the starter bolts making contact cause an intermitent noise?

Tom, I did hone the bushings in the distributor and oiled them when I assembled it, also since the car had sat over the winter months I oiled them again when the noised started and later removed the distributor to check and it spins easily by hand.

Glenn, I had the same thought and checked the manifold area for leaks and retorque those nuts as well.

It's beginning to sound like the cam plunger may be the culprit but I will also try oiling the front seal, I am borrowing a stethiscope from a friend and will check the area on the front cover, I just never realized something internal could make a sound like this.

Thanks also for the compliments, the car actually belongs to a good friend who asked me to assemble it for him, turned out to be a great learning experience.

The landau irons and their trim pieces were the toughest parts to find, luckily even though it was pretty beat up the belt rail molding was still with the car.
 
I had a leaking carburetor gasket that made a horrible and hard to locate sound like that, and it too only started after a warmup. Just saying.
 
Ted, did you find the source of the screeching? When my cam plunger ran dry because the oil hole was plugged it wore out the cylindrical hole and I had to replace the timing cover. It didn't screech for more than a few minutes but it opened that bore right up and left some ground up cast iron as evidence.
 
Using the stethescope I tracked the noise to the front of the engine so it looks like the cam plunger was the problem, my friend wasn't too enthused about the amount of work involved to replace the plunger and wanted to try and lubricate it somehow.

I removed the side cover at the cam gear and using a flexible plastic tube I sprayed some Red Grease onto the area of the cam plunger, then with cover off started the engine and sprayed a little more, we ran the engine for about 15 minutes with the cover held on with just the top bolt and it was quiet as could be so we shut it off and reinstalled the cover then restarted it.

We ran the car for about 20 mins. varying the idle speed from time to time and then he took it for his first drive, just a short distance out the driveway and back to test the brakes, since all seemed fine I followed him the 4 miles to his house.

Once there we let it run for another 10 mins. or so without any strange noises.

Thanks again to all who responded.
 
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