Clutch issue

[hottigr]

I have a clutch issue that just started a couple of drives ago. A little background- the clutch is a McCleod 10.5-inch unit that Rick was selling in 1990. I believe it was a 2200 lb. clutch that Rick was taking off every other spring to give it 1700 lb. of pressure so as not to overwhelm the Tiger’s hydraulics. I have the stock close-ratio Toploader. The clutch is almost 35 years old but doesn’t have a lot of mileage on it. It shifts fine, travel and engagement while underway is fine. Where it’s not happy is in stop and go traffic, where a few pushes of the clutch pedal in a short amount of time causes a gear-grinding sound occasionally while the clutch is trying to release or engage. Note that I am not changing gears; it’s happening in 1st gear while just pushing the clutch in and releasing it. Happens at the bottom of the travel. I could understand the gear grinding if I was shifting but I’m not. That’s the head scratcher for me. Opinions? Thanks. Kirk

 

[IvaTiger]

Sounds like a hydraulic problem even a small amount of junk or decomposition of the rubber parts in the master or slave cylinders can lead to slow release or engagement of the clutch Sticky seals.
Try flushing and replacing the fluid or best to rebuilt both cylinders

 

[hottigr]

Any idea why I am hearing gear grinding when I'm not shifting- just pushing the clutch in and out in 1st gear?

 

[pfreen]

If you are lucky, it is the throwout bearing on its last legs. I suppose it could be the spigot bushing also. If you are not lucky, it could be the transmission.

 

[hottigr]

I would suspect throwout bearing or pilot bearing also, but I can't get my head around anything that would cause gear grinding when it's already in gear and I'm not shifting- just depressing the clutch and letting it back out again.

 

[boss-tiger]

Probably a good idea to consider a new clutch setup and rebuild clutch master/slave just to cover the bases. Also confirm your flywheel is ok (?if any problems, hard spots, stress cracking), ring gear, new pilot bushing - plenty of opportunity for you to spend $ McCleod clutch/treasure plate combo was a beast (but the brand I heard most often recommended for Tigers back in the 80's, I had one and it had some serious pedal effort required for sure). I have now and highly recommend you look at Centerforce clutch components.

 

[HolyCat]

I would suspect throwout bearing or pilot bearing also, but I can't get my head around anything that would cause gear grinding when it's already in gear and I'm not shifting- just depressing the clutch and letting it back out again.

Taking a shot in the dark with my very limited knowledge of tannies, when you press in the clutch and let it out while car was in gear and you are hearing grinding noise, is it possible that there is a bearing (or two) in your tranny which allows the gears to not mesh properly when the tranny is unloaded? I hope I am wrong, since R & R your tranny is not cheap, nor is rebuilding your tranny. Good luck with whatever is causing the problem.

 

[hottigr]

Taking a shot in the dark with my very limited knowledge of tannies, when you press in the clutch and let it out while car was in gear and you are hearing grinding noise, is it possible that there is a bearing (or two) in your tranny which allows the gears to not mesh properly when the tranny is unloaded? I hope I am wrong, since R & R your tranny is not cheap, nor is rebuilding your tranny. Good luck with whatever is causing the problem.

Dave, that is something I had not thought of, and sounds reasonable, although I'm hoping it's not!

 

[woody6]

Here's a possibility, albeit an unlikely one. When I got my car 37 years ago, the clutch was heavy, and it was even more so after I put a heavier duty clutch or pressure plate in it. It would also act funny at the bottom of the pedal travel, like it was trying to engage the clutch rather than to disengage it. Upon disassembly I found out the the previous owner had put a larger bore master cylinder in it, which was causing the throwout bearing to press the clutch release fingers so far down that they would start touching the clutch disc. I do not recall a grinding noise when this happened, but it would explain what you describe.

 

[hottigr]

Interesting... having rebuilt my clutch and slave cylinders many times I can safely say they are stock. Glad you figured out what was causing your noise!

 

[woody6]

Interesting... having rebuilt my clutch and slave cylinders many times I can safely say they are stock. Glad you figured out what was causing your noise!

Glad you can eliminate that as a possibility without taking things apart. I would otherwise suspect a throwout bearing, but I cannot imagine what would be making grinding sounds when the pedal is moved only near the bottom of the travel. Good luck, do let us know when you find the solution.

 

[hottigr]

Took the Tiger out today...it was good on the drive (45 minutes), but, while attempting to get the car straight into the garage (which requires some back and forth on the uphill driveway apron) I was able to replicate the sound. While out driving I tried to pretend it was my first time in the car, taking note of every little thing. Some things I may have taken for granted that might contribute on the whole to the problem I am having. I normally don't depress the clutch all the way to the floor while shifting, trying to minimize the RPM drop to mesh the syncros. It's not much, maybe a half-inch off the floor, but today I depressed the pedal all the way down before shifting gears to make sure there was no possibility of that being the issue. Another thing I noticed was the clutch pedal engagement, while certainly not immediate, was closer to the first half of travel than at the top of the travel. Something else- my idle is set around 850 RPM's. I've had it slower in the past, as low as 600 RPM's, but the car is much happier at the stoplights at 850 right now. This idle speed might keep the pilot bearing spinning a little between shifts. In addition, the age of the throwout bearing, combined with a little extra stiffness in the clutch springs due to age might be causing the throwout bearing to bind on the shaft sometimes. Any or all of these things could come into play, and probably do when the issue presents itself. That's all I got for now! Thanks for everyone's input.

 

[Austin Healer]

Here's a possibility, albeit an unlikely one. When I got my car 37 years ago, the clutch was heavy, and it was even more so after I put a heavier duty clutch or pressure plate in it. It would also act funny at the bottom of the pedal travel, like it was trying to engage the clutch rather than to disengage it. Upon disassembly I found out the the previous owner had put a larger bore master cylinder in it, which was causing the throwout bearing to press the clutch release fingers so far down that they would start touching the clutch disc. I do not recall a grinding noise when this happened, but it would explain what you describe.

this is the most likely culprit.... but it could also be lack of free play in the master. When your foot is off the clutch pedal there has to be some free play or the master can't bleed off pressure. This will cause it to do the same thing as having an oversize master...

 

[hottigr]

Well, after a few more drives and a couple more incidents, I think David Wilson is our winner! The problem doesn't appear to be clutch related after all. I'm not a transmission expert, but it appears to be in the first gear cluster. The clutch operation is normal. If it didn't have enough free play, it would be riding on the throw out bearing. If it didn't totally dis-engage at the bottom I would not be able to shift or I would have creep with it in gear and the pedal depressed. Clutch engagement is fine. The gear grinding (and it is gear grinding) happens when I'm in first gear and have to depress the clutch a lot- like trying to get the Tiger into just the right spot in the garage to park it. There is no shifting involved. Something about loading and unloading the gearbox in just the right (wrong?) conditions in first gear causes it to happen. Thanks for all the input.

 

[0neoffive]

Well, after a few more drives and a couple more incidents, I think David Wilson is our winner! The problem doesn't appear to be clutch related after all. I'm not a transmission expert, but it appears to be in the first gear cluster. The clutch operation is normal. If it didn't have enough free play, it would be riding on the throw out bearing. If it didn't totally dis-engage at the bottom I would not be able to shift or I would have creep with it in gear and the pedal depressed. Clutch engagement is fine. The gear grinding (and it is gear grinding) happens when I'm in first gear and have to depress the clutch a lot- like trying to get the Tiger into just the right spot in the garage to park it. There is no shifting involved. Something about loading and unloading the gearbox in just the right (wrong?) conditions in first gear causes it to happen. Thanks for all the input.

Wobble !! One of my clients sent me a Tiger with similar issues and other defects to remedy. I found that the pilot was very worn and oversized hole. The input needles were marginal as was the input bearing. As pressure changed with the throwout moving the input shaft would wobble enough to allow the selection guides to make contact. 2 cents

 

[hottigr]

And there you have it! Perfectly explains what is happening!! Just took someone with enough expertise to figure it out. Now, if I was 3000 miles closer to you, I'd be set LOL! This is not something this 70-year-old is going to try and do on his back in the garage with the Tiger on jack stands! I'll continue to drive it until it gets much worse, or I find someone in Socal that I can trust to do it. My local Tiger guy passed away a few years ago...Thanks, Randy! Kirk.

 

[0neoffive]

And there you have it! Perfectly explains what is happening!! Just took someone with enough expertise to figure it out. Now, if I was 3000 miles closer to you, I'd be set LOL! This is not something this 70-year-old is going to try and do on his back in the garage with the Tiger on jack stands! I'll continue to drive it until it gets much worse, or I find someone in Socal that I can trust to do it. My local Tiger guy passed away a few years ago...Thanks, Randy! Kirk.

I'll be in SoCal Christmas week haunting the Sandy Eggo grandkids. Will also drift down to Smitty's with my coffee mug and rag pick thru his assortments of booty. The shops here will be shuttered while most of the crew trailers their toys south.