Pilot bearing / clutch noise

[moodyblue]

I have just changed the gearbox mounting on my wedge, the old one had swollen to double size due to the usual oil leak. The job was a bit of a pain with the L/H side of the car jacked up. Everything was cleaned and a 1mm profiled steel cover was installed between the mounting spacer and the gearbox to protect it from oil contamination, as discussed elsewhere on this forum.
Now for the problem, when starting the car the starter makes a strange noise, the pilot bearing is grinding (stops when I press the clutch), it's harder to select gears and there is more vibration when ticking over and driving.
Could something have changed when the car was jacked up and the gearbox supported with a jack?
All this for changing a mounting, nightmare!

[dursleyman]

Don't see how bearing noise can be connected with your job. Are you sure it is the pilot bearing?

Russ

1980 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

[moodyblue]

That's what I don't get, very strange. I think the gearbox must be resting partly on the drip shield I fitted and not fully allowing the mounting to do its job. The bellhousing would still be taking the weight so any upward pressure wouldn't affect the pilot bearing, but it's got all the signs of that problem. Anyway, tomorrow morning I'll remove the metal shield and see if that sorts it.

[Workshop Help]

Okay, I'll start the speculative abuse and official ponderings.

Just to get ourselves organized:
1. Your custom oil shield has nothing to do with this new development.
2. A 'strange noise' when you hit the starter.
3. The 'pilot bearing' is 'grinding' then stops with the pressure plate disengaged.
4. Vibration and sticky gears.

So, after divining in the crystal ball we borrowed from the Wizard of Oz, I mystically peer into the near future to behold you personally supporting a LT77 gearbox on your chest as it is pulled from the flywheel. Oh! What wonders will you see? To begin with, will the throwout bearing have a gritty kind of sensation as you spin it? Is the pilot bearing all dry and lightly scored? Is the dimple on the clutch fork about to turn into a drain hole for errant clutch push rods? Are all the teeth on the flywheel ring gear intact?

Because of our prurient nature, we will thrill to your upcoming photos and adult documentary in answer to these questions. Just remember, the only thing less fun than pulling the gearbox, is putting it back in.

Mildred Hargis

[Hasbeen]

There is just a chance your problem may be inexpensive, & easily fixed.

There should be a round steel spacer about 2" diameter & an inch or so thick included in the mount system. It should be immediately under the box, & above the rest of the mounting paraphernalia.

It is not shown or mentioned in the early workshop manual, but does appear in the Rimmer Bros. catalogue.

I believe it is a late afterthought addition by Leyland after they discovered how much an oil soaked rear mount would sag. You see it sags enough to allow the gearbox to actually sit on the subframe.

When this happens you get the symptoms you described. With the physical contact between box & body, via the subframe, all the mechanical noise of the spinning meshed gears is transferred to the body,

The noise is amplified to reverberate through the body. The first time I heard it, I thought the gearbox was about to disintegrate, in a shower of shot bearings.

The noise being simply nothing more than reverberating normal mechanical noise is nothing to worry about. It also DISAPPEARS, when you step on the clutch pedal, disengaging the clutch, & thus stopping the gears rotation, if the car is at rest.

Two things to check;

1/. Is your gearbox sitting on the subframe. Probably not as you mention the spacer.

2/. Is your carefully fabricated gearbox mounting umbrella sitting on the subframe, or other body part. If so it is probably guilty of the same noisy result as sitting the box on the subframe.

I have been known to be wrong on more than a few things Triumph in my day, but I really hope I am right on this one. Do make sure the car is sitting with everything loaded as it is when not jacked up, with a driver onboard.

If no other facility is available, a narrow ditch the car could straddle could perhaps be found. Jacked up by the chassis could give clearance where none occurs when on it's wheels.

Good luck, & happy ditch hunting.

Hasbeen

[moodyblue]

Thanks Hasbeen, you're spot on. Thank goodness! It was my oil shield creating the problem and it was all vibration. I'm going to take this back to the original post now and load a picture of the oil shield as I should have posted on there and not opened a new topic, sorry folks, I'm still new to this.