Squeaking near front crank pulley

C

cbeckman

Junior Member
My Model A engine was quiet for > 10,000 miles after rebuild when a new squeaking or scraping sound developed at the front of the engine. Removal of the fan belt does not eliminate the squeaking, ruling out the generator and water pump. Stepping on the clutch does eliminate the noise, suggesting that a slight movement of the crankshaft forward might be removing contact between the pulley and the front motor mount. However, there is no loss of paint from the motor mount. Inspection of the pulley with generator removed using a wood 1/8" dowel and inspection mirror shows approximately 3/16" clearance between the pulley and 1) the motor mount base, 2) the auxiliary spring, 3) the motor mount upper arm confluence, 4) and the upper two springs and their mounts. The pulley is an original one piece pulley that has no wiggle when idling or manual looseness, and the ratchet nut is tight. At idle, I do not see any front to rear movement of the pulley (or crankshaft). Stepping on the brake pedal during idle does not eliminate the squeak as did the clutch pedal, which makes it unlikely that the rear motor mounts are allowing the entire motor to move with clutch pedal force. Below the front cross member, the motor mount stud is secured with a flat washer, spring below this, and then castle nut and cotter. This lower spring is not loose and is moderately compressed. The squeaking is quite noticeable at idle and driving. I am left with the conclusion that the motor mount stud could be rubbing on the rear of the crossmember hole but why doesn't this happen with all Model As that show wear in this area?
Has anyone had a similar problem? Thanks Charles Beckman
 
How did you rule out the generator as the source of the squeak ? Original generator ?

Engine squeaks can be hard to identify unless you use a stethoscope, or funnel and piece of rubber tubing to pinpoint it.
 
my thoughts as i just went through a problem with the crank moving ahead when the clutch is pressed down.

-take off your clutch inspection cover (were you grease the throw out bearing).
-start the engine and watch when you press on the clutch to see if there is noticeable forward to back movement of the flywheel. this is crankshaft endplay.
-if the crank has excessive end play it could be moving ahead and it touching something inside. maybe the front main, maybe the oil slinger washer touching the cover, maybe the cam plunger, maybe it just changes the position it is rubbing on the seal.

endplay is supposed to be .003" but lots of model A have way more and don't make a noise.

mine had .035" end play and was moving ahead and the flywheel hit the bell housing. sounded like the rods were coming out of it. (it was hard to find)

another thing
the engine should not move ahead when you press the clutch because the pedal pivot it on the bell housing not the frame. it would be very difficult for you to shift the position of the engine by pushing on the clutch pedal.

if yo think it is the front mount touching the x member, just take off the bottom nut and start the car, push on the stud while it is running and see if the noise changes

ou
 
cbeckman said:
Stepping on the clutch does eliminate the noise...
Click to expand...

old ugly said:
my thoughts as i just went through a problem with the crank moving ahead when the clutch is pressed down.

-take off your clutch inspection cover (were you grease the throw out bearing).
-start the engine and watch when you press on the clutch to see if there is noticeable forward to back movement of the flywheel. this is crankshaft endplay.
-if the crank has excessive end play it could be moving ahead and it touching something inside. maybe the front main, maybe the oil slinger washer touching the cover, maybe the cam plunger, maybe it just changes the position it is rubbing on the seal.
Click to expand...

Good point but the OP stated the squeak went away when he pushed in the clutch.
 
I had a similar "hard to find squeek", it was where the front motor mount sits on the crossmember. Squirt a little oil on that, it's worth a try..
 
Had the exact same situation on my truck that you are describing. The two bolts securing the front motor mount were slightly loose. Tightened them and the noise went away.
 
I bet you have soft engine mounts. Pushing in the clutch will slightly move the engine forward and stop the squeak caused by the bolt for the front engine mount where it goes through the front crossmember. Don't ask how long it took me to find that one!
 
If one is chasing noises and they don't want oily messes, one could spray water around suspect noises and when the water dries no messes. When driving a modern and hitting a water puddle squeaks go away and come back on sunny days.
 
I had a similar problem. but mine would only squeak while driving down the road. turned out it was from the left engine pan rubbing on the front cross member. my car have float A motor mounts and the allow the engine to move more so than the original mounts.
 
Found the similar front "squeak" was attenuated by adjusting the front motor mount castle nut at the spring. Also, replaced the flat washer with the special brass washer that fits in the member hole and that helped to get the spring adjusted per the Service Bulletins Specifications.
 
I had the same squeeking noise after completing the restoration on my 29 roadster. It would go away when stepping on the clutch leading me to think it was the throw out bearing. I then realized it was coming from the front of the engine, removing the fan belt didn't make it go away. A squirt of oil onto the motor mount where it passes through the front crossmember stopped the noise. Almost 8,000 miles later it is still quiet.
 
Loosen or tighten the nut under the crossmember for the front engine mount, while the car is running.
 
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