Troubleshooting Clutch Issue

A

austinx19bill

Daily Driver
Background.

1981 X1/9, acquired in 2017, let it sit idle for about a year (triaged other projects).

When I got to it a couple months ago, it wouldn't start and the clutch pedal went to the floor and wouldn't return.

Starting issue was the starter, pretty straightforward replacement. (It had been intermittently failing but I ignored it, hoping it would heal itself, thankfully not a more complicated ignition or other wiring issue.)

Turning to clutch, the slave looked like it had failed, so replaced master and slave. (What a PITA to work on the master.)

Flushed all the lines before installing new master and slave and bleed hydraulic clutch circuit after install until clear fluid (no foam).

Clutch release arm now moves via the slave cylinder, but still no clutch (disengagement).

Did I get the adjustment wrong?

Or has the throwout bearing failed as well (so no clutch release) and the throwout and slave cylinder failures were just coincidental?

Any thoughts on how I can determine what the problem is?
 
Possibly the clutch disc is stuck to the flywheel. I seem to recall a seeing a way to try and free it by rocking the car in gear, but need to be careful not to over do it and bend something in the tranny. Definitely don’t do it in reverse. If the release arm is moving then it’s either that or you are looking at dropping the transmission. Hopefully more knowledgeable folks will chime in.
 
In addition to Rogers suggestion....
Not sure if it may be related, but there are two little "hairpin" clips that hold the throwout bearing to the clutch fork. They are not a great design in my opinion and seem to fall off easily. I've found them loose or missing on several trans. If one or both has come off then the TO bearing could either be jammed or not in place any longer. The fork pivot also seizes commonly, but you say that works. Notorious for air to be trapped in the hydraulic system despite persistent bleeding, but you say the slave is working.
Does it feel like there is any resistance from the pressure plate springs? If so then most likely a frozen plate that Roger detailed. Any connection between the engine and trans? By that I mean when the trans is in gear will the car roll easily or does it have resistance from the engine compression?
 
Roger is likely correct and its a common problem. Typically, when a car sits for an extended period the clutch disk will stick to the pressure plate and flywheel. Having somebody push the pedal to the floor and rocking the car in 1st gear, will break it loose.
 
Another method can be to lift the car, put it in first hold the clutch down and then heal and toe the brake and gas to break it free.

I have also seen the following but don’t suggest it: With the car on a jack start the car, rev it up in gear hold the clutch down and with a healthy bit of gas, drop the car on the ground and it will break the clutch free.

Make sure you are pointed at an open garage door.
 
years back I had this happen on an old piece of farm equipment. We did the gentle approach and were down to pulling it apart, but really did not want to take the old thing apart. It would run, you could start it in gear. to add to things it had no breaks, so we had another tractor chained behind it to act as breaks. Got everything moving forward with the clutch held down the tractor behind would add a lot of drag (dropped the disk into the ground. a little of this and the disk broke loose from the flywheel and we never did take that thing apart. But on the other side, tried it again on a hold homemade forklift, ended up ripping the disk in two, destroying it. (got lucky on this one as the transmission was belt-driven from the motor and was an easy removal and found a disk at an old tractor shop.

unless you are going nuts with how violent you are getting I can only see you are risking damaging the disk (which you would replace anyway if you removed the trans anyway) there is not much risk to trying to break it loose before pulling it.

I hope you keep us in the lope of what you do and what happens!

We LOVE!! pictures,
 
kmead said:
Another method can be to lift the car, put it in first hold the clutch down and then heal and toe the brake and gas to break it free.
Click to expand...

Or, if the car is on the street with no other car in front of it, what I did in the past, when my clutch hydraulic wasn't working, I put the car in gear (first) and turn the key. It's not what is the best in the long run for the car longevity, but it may force the car to move forward and may help you find the problem. (Basically, what is Rod also suggesting, I think).

BTW, the intermittent starter is often cured by the brown wire mod, extensively discussed in past threads.
 
I'm not sure, but if the clutch disk is frozen and you manage to break it free, would you want to replace it anyway? Seems it wouldn't last very long after the whole incident. And IF that was the case, then why not just go straight to removing the trans and replace it in the first place? That gives you the opportunity to verify the condition of the flywheel, pressure plate, TO bearing, etc, and also do some maintenance of things (fork pivot, etc).
However on the other hand I'm sure the disk might be usable for some time after freeing it up. Honestly I've never had one stick, likely due to the mild climates I've lived in, so I'm not certain what you'll end up with.
 
I wonder if there is any amount of force you can put on the fork lever manually to determine if the clutch is frozen (i.e., if its not stuck, can you push it yourself as if it was being pushed by the slave), or can that only be done by hydraulic force? I'm thinking if you can move the fork, you'll know its not a frozen clutch and look elsewhere for the problem.
 
Mike, I suppose the disk could be stuck to the flywheel while the pressure plate (and fork) still moved about?
 
I used to do stuff like that (run cars while on stands). I guess I've either become wiser or more afraid, but I wouldn't do it that way either.
 
Yes this is what is happening, the disk is stuck to the flywheel and the clamping force of the pressure plate is no longer on the opposite side of the disk. The pressure plate has been moved away from the disk by the fork.

This is why you hold the clutch down while moving the car with the engine running and then using the brake to create a force the clutch disk being the ‘soft’ intermediary will then shear the rust attachment of the it to the flywheel.
 
well if you don't break the disk lose before you pull it. you will have to do it afterward, don't know how tough that would be.
 
I'm really bad about leaving cars parked for years. I've freed clutch disks using the method Karl suggested and it always worked for me. I raise the rear wheels and warm up the car in neutral. Then I start the car in first gear. I then slowly apply brake with the clutch pushed in. More gas and more brake add shear in a controlled way to prevent clutch damage. At some point the clutch pops free and everything is back to normal. Lower the rear wheels and take it for a drive riding the clutch a bit to polish the surfaces and remind yourself not to leave your car parked so long!
 
Wow, lots of replies -- too bad I wasn't getting email notifications of all the action on this thread.

First Daniel Forest: tested wiring, and it was was all good (no brown wire issue - whew), put old starter on bench, couldn't get it to engage at all from 12V battery, took to autozone to test, definitely dead, Auatozone "carries" starter for $50 but none in stock nationally and no line-of-sight as to when they would be in stock, so just got a rebuilt for $40 after core exchange on Rock.

Got the clutch pivot to finally have tension in it last week -- not sure what the issue was but maybe the disc stuck to the flywheel.

Just rocked it a bunch like everyone suggested and suddenly the clutch pivot arm magically developed resistance.

Changed oil/filter, gas filter, cleaned K&N air filter.

Didn't ride the clutch to polish off the rust, but filled it up with pure gas (no ethanol), drove it in a spirited fashion about 75-80 miles (at an average of 85-90mph) with no more clutch issues to a friend's ranch where I entrusted the keys to his 15 year-old son, who offered to drive up and down their ranch road (RR here in Texas) "test track" occasionally for me. As he texted his friends "guess what I'm driving? a mid-engine Italian sports car".

Still has an issue that the fuel pump can be finicky at startup -- sometimes it runs with the switch on, sometime not. But once running doesn't die in the middle of a pass on the interstate or anything like that. Guessing it is in the ignition key wiring.

So fingers crossed the clutch doesn't stick again or else I am just going to dive in and do a clutch job. (Would be a good excuse to start a rotisserie restoration?)

Otherwise, the most fun I've had under 100mph in a while. Engine revs freely and feels like it'll run all day at 4,500-5,000rpm.

Looking forward to a full restoration of it in a couple of years (hopefully -- or sooner if the clutch goes).

BTW, looks like Cratecrusher and I are kindred spirits.

My stable (shared in part with my brother):

'32 Deuce Coupe (with Saab 2.0 motor, weird but popular in UK and Sweden, brothers)
2x '40 Fords (brothers, one a decent roller, one nicknamed "tetanus")
2x VW Sandrails
'73.5 911T (full body-off restoration, pride of the collection, mine)
'73 Vette
'74 914 roller
'79 Firebird Formula (brothers)
'81 X1/9
'82 RX7
3x 85' 944s (hope to get 1 outta the three, brothers LS 948)
1x 86' 944 (son's)
'86 928s
'88 924s
'92 Ninja
'99 Boxster (brothers)
'00 Boxster
'04 Land Rover D2

Think that's it. About half actually run.

Not including wife or kids cars.
 
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