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Tips
Tips

TR2/3/3A Squeaking Clutch when hot

Haven’t been able to tell yet. Getting a mechanics stethoscope tomorrow to try and locate it.
Any chance the clutch could make noises like this?
 
Wow I am impressed your camera did a great job. I thought the scope deal would get eaten with that stuff whirling around. I took out a clutch disc once and those little springs that go around the center of the disc were lose and rattled, but I do not remember there being a noise.

The trans does not come out easy, so you have my sympathy. I would probably get a different clutch and try that, but I am guessing.

steve
 
Here are the possible items, and "no" the clutch is not making the noise, since it is inert when the pedal is out.

1) clutch cover plate...the usual cause of this type noise.
2) Flywheel bolts too long and rubbing on the block/#3 main bearing
3) Starter pinion rubbing against the flywheel.
4) Flywheel ring gear set too far aft and rubbing on starter or block
5) Badly ground camshaft allowing cam to walk for and aft, and rubbing on front cover.
6) cam rear end plug set too far in and rubbing on end of cam.
7) #2 main bearing thrust bearings worn out or missing
8) spun main or con rod bearing
9) Loose or bent baffling in the oil pan
10) Oil pump drive shaft bushing worn and allowing the shaft to chatter
11) Loose advance mechanism in the distributor and/or worn bushings allowing unit to chatter
12) Starter or dynamo bearings worn, allowing the armateur to contact the stator coils
13) Worn water pump, allowing rotor to contact housing.

"And that's all I have to say about that".
 
Yowsa, a much larger list than I thought. Here’s my thoughts and findings on some of these. Nothing stated as fact, just some thoughts.

1) clutch cover plate...the usual cause of this type noise.
Eliminated by temporarily replacing with a plastic plate. Noise still present.
2) Flywheel bolts too long and rubbing on the block/#3 main bearing
Unlikely as these didnt change?
3) Starter pinion rubbing against the flywheel.
4) Flywheel ring gear set too far aft and rubbing on starter or block
Unlikely as this didnt change?
5) Badly ground camshaft allowing cam to walk for and aft, and rubbing on front cover.
I’ll check end float to see if in spec.
6) cam rear end plug set too far in and rubbing on end of cam.
7) #2 main bearing thrust bearings worn out or missing
I’ll check end float
8) spun main or con rod bearing
9) Loose or bent baffling in the oil pan
Unlikely as noise affected by clutch pressure.
10) Oil pump drive shaft bushing worn and allowing the shaft to chatter
Unlikely as noise affected by clutch pressure.
11) Loose advance mechanism in the distributor and/or worn bushings allowing unit to chatter
I’ll check with stethoscope
12) Starter or dynamo bearings worn, allowing the armateur to contact the stator coils
Eliminated by removing belt. Noise still present.
13) Worn water pump, allowing rotor to contact housing.
Eliminated by removing belt. Noise still present.
 
Crank Shaft end float is 0.0085”. Spec is 0.004” - 0.006” but from what I’ve read, that’s not critical. Manual says 0.015” is the wear limit.
Not sure what that tells us other than the crank is not moving too far forward.
 
When you say some are not affected by clutch pressure, you must remember that when pressing the clutch pedal, you are physically pushing the crankshaft to its forward limit. When the pedal is released, the crank tends to fall to its rear limit, as the engine sits angled rearward in the car. when revving with the pedal released, the crank will tend to "bounce" off the rear limit by dynamic forces. My point is that literally everything in the engine is connected in some way to the crankshaft and can be affected when you are moving the crankshaft for and aft with the pedal...
 
I figured that forward and aft pressure wouldn’t transfer much to the cam shaft, but possibly it is via timing chain? If it transfers, then I’ll include distributor and oil pump as well. Hopefully stethoscope tonight can isolate the noise a bit more.
 
Well no luck. With mechanics stethoscope couldn’t detect the noise by touching the following: Water pump, fuel pump, generator, starter, distributor, valve train, oil pan front, oil pan back, bell housing, transmission, block front, block back, clutch cover plate. May have to remove the pan and check oil pump and bearings.
 
I take it you still have the tunnel cover off so while you have the stethoscope check the exhaust where it goes through chassis, remembering the noise only starts after the engine has warmed up. I can't think of anything in the drive train that would be affected by heat expansion, but the exhaust could be.

Graham
 
I’ll check it, but the noise is definitely rotational, increasing/decreasing with RPM. One other observation, if I run longer (more heat), the noise is persistent, not just over 1200 RPM. If I let it cool down over a few minutes (while putting on jack stands after a drive), the noise will go back to just over 1200 RPM or if I let it cool down a few more minutes, noise is gone again. I can bring the noise back by idling on jack stands.
 
Over the last 55 years, I have had transmissions that would grind shifting when the engine warmed up, but while the engine was cool the transmission was fine and much quieter. Maybe that helps---- still guessing

Steve
 
Shortly after I finished my TR2, it started to make a strange rattle when accelerating in 1st gear. I went through a similar diagnostic hair puller to what you are going through. Here is a fun thread I posted guessing what it ended up being...


Well...within 6 months, the car started making a similar sound, only when starting from a stop in 1st gear...again! I immediately assumed it was the same problem. It wasn't. I then went through the items that could possibly cause a breakdown. I finally gave up. I decided the amount of work finding it was not worth the annoyance of the slight rattle. If I let it get worse, then I could address it later. That was 6 years ago!! The car still has a slight rattle when starting from a stop. It has gotten no worse, and even after many tune-ups, oil changes, and grease jobs with the car on the racks, I still have no idea where it comes from.

My point is you may reach a point where your sound is like mine. If it is something bad, it will get worse and become easier to diagnose! Just a thought.
 
You could try the old cure-all for rattles and squeaks, turn the radio up and they all disappear.

Graham.
 
I considered letting it ride, but the noise gets louder and more persistent the longer I run, so I hope to fix it.
Focusing on the list CJD provided, I plan to remove the starter and push start the car to eliminate the starter from the list.
 
I also confirmed at lunch today that just the SLIGHTEST pressure forward causes the noise to start (after hot of course).
The parking lot at work has just enough grade on it where I can roll forward in neutral.
No noise while rolling but when I press the brakes just enough to stop the car from rolling, the noise is present.
When I let off and car rolling forward (even just an inch), the noise stops.
I repeated this several times.
Of course there is nothing moving in the brake system while stopped, so it is the forward pressure on the drive train that does it.
Amazing how slight the pressure is to cause it.
 
Before you take the starter motor out, which is not an easy mission, (the rear carburetor has to come off to get the starter out), with the engine running put some forward pressure on the engine transmission to see if you can reproduce the noise.

Graham
 
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