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I'm really stumped on an issue that's recently come up with my 86 Turbo HCI. Hoping one of you guys may have an idea, or be able to point to something that I've been overlooking.

Problem: I can't shift into gear while the engine is running. Presumed it was a clutch hydraulic issue and replaced the clutch master and slave cylinders, and hydraulic line this weekend. Still can't shift into gear.

Background: The last time I drove the car, it gave symptoms of the clutch hydraulics going out. I was having trouble shifting into gear, and could feel the car pulling while stopped with the transmission in gear, clutch in. It got progressively worse in a hurry, and at the end of the drive I couldn't get the car in gear at all with the engine running. Unfortunately I had to let the car sit for a while I traveled for work, but when I came back nothing had changed. I checked the clutch master cylinder reservoir, and found it was empty.

After swapping out the entire hydraulic system this weekend and bleeding, I verified proper movement on the pushrod and release fork. However I haven't been able to locate a spec on how far the pushrod/fork should be moving, but visually it looks like it would be adequate. ( I do have the 22 mm on the release fork adjuster screw).

Even after this repair, the car is stuck--won't go into gear. After a brief bit of research it sounded like maybe the pressure plate had stuck to the flywheel. I tried to break it by heat soaking the transmission, letting the car idle for quite a while with the clutch pedal depressed, stopping the engine, then hitting the starter with the car in gear. Nothing.

What am I missing here? Is it possible or common that the release fork has broken inside the transmission? I can verify operation externally. I'd really appreciate anyone’s input or suggestions.

As an afterthought, anyone happen to be located near Greenville SC?
 

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On Esprits with the UN1 transmission there is a small square port or access opening in the bell housing. You can see the throwout bearing a part of the clutch fork from there - and you can get a small inspection mirror or boroscope in there to verify the proper movement of the TO bearing and fork. I don't know if the Citroen trans had such an arrangement.

The fork is pretty beefy - hard to imagine it just breaking. It may have somehow fallen of its pivot point. That I think is more likely than it breaking.
 

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Oddly enough, my friend's fork broke twice on his S4. I'm assuming it was misadjusted in some way.

The original poster has a Citroen trans, but I'd say more bleeding is needed before going any further.
 

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Honestly, it could be quite possibly that you simply hadn't bled enough. S2Mikey and I just replaced his clutch master cylinder on his 87 HCi today, and after bleeding, we started the car and couldn't get into gear.

A whole lot of further bleeding later and it was fine. These cars seem to take quite a bit of bleeding to get right.

Also, on your slave cylinder, where is your bleed nipple oriented? Is it in the bottom position, or the top? If it is in the bottom, you will never bleed it adequately. If that is the case, flip it around and then bleed it again.
 

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Honestly, it could be quite possibly that you simply hadn't bled enough. S2Mikey and I just replaced his clutch master cylinder on his 87 HCi today, and after bleeding, we started the car and couldn't get into gear.

A whole lot of further bleeding later and it was fine. These cars seem to take quite a bit of bleeding to get right.

Also, on your slave cylinder, where is your bleed nipple oriented? Is it in the bottom position, or the top? If it is in the bottom, you will never bleed it adequately. If that is the case, flip it around and then bleed it again.
Mega-dittos on this. We bled, then we bled some more.... and just when you are 100% certain there isnt anymore air in there: Bleed it a little more. Yeah. The systme traps air like crazy and even a tiny amount screws the whole system up. I bet thats your problem.
 

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Discussion Starter #6
Well, thanks for all the input. Obviously it would be good news if it's just more bleeding, but I thought I'd done quite a bit so far. I’ve actually been bleeding the system with the slave out of the mount (slave vertical), bleed nipple vertical. This would be even better than as mounted (slave horizontal), bleed nipple on top, yes? The last time I bled I was able to get 4 or 5 pumps without seeing any air, but I’ll give it another go in the next couple of days.

Ideally I’d have a way to verify this is the issue. Can anyone give me a rough estimate of how far the pushrod/fork should be moving for full travel? Has anyone figured out a way to push/hold the release fork while the slave is out, just so I can try and rotate the rear wheel and check that nothing inside the transmission is screwy? If I try and hold the clutch pedal down with the slave in, pushrod and fork actuated, I can't rotate the rear wheels.
 

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Wingless Wonder
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I've had good luck with clutches by propping the pedal down to the floor overnight. Sometimes this allows any air bubbles to escape out of the reservoir.


It's Quick, Easy, and Fun. :p






Another technique for removing air is to give the pedal two or three quick strokes at the beginning. This pushes the air to a section of the line where it can be more easily bled by the usual, slooow, pedal depression method (which prevents air bubbles).
 

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I back bleed a clutch slave on a Saab, think it required putting a hose on a front brake caliper open nipple and attaching the other end to the slave nipple opened.
Kind of a 'reverse' action. It's a sealed system but the fluid coming out of the caliper pushes the air up through the slave into the master. Must make sure rags are placed over the master cap to avoid leakage.

Did you jack up the rear so the air will travel up? There is so much line air bubbles get trapped. When I worked on VW Vans the radiator was in the front with engine in the rear so you had to jack the rear to bleed the system.
Air will go up, not down.
 

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Brake guy here. Not familiar with your clutch reservoir but i have had good luck getting air out of brake systems by pulling a vacuum over the reservoir. Get your hands on a mighty-vac and i have used any number of things to cap the reservoir, a hockey puck with a hole in the center works well. Put the puck on top of the reservoir in place of the cap, a little brake fluid helps it seal and use the mighty-vac to pull a vacuum on the reservoir through the hole in the puck. You can leave it on as long as you want. The air in the system will propagate back to the reservoir and any microscopic air dispersed in the fluid will come out. Doesn't beat a normal bleed but usually gets that last bit of air you can't force out.

Sent from my MB860 using AutoGuide.Com Free App
 

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I've had good luck with clutches by propping the pedal down to the floor overnight. Sometimes this allows any air bubbles to escape out of the reservoir.

It's Quick, Easy, and Fun. :p

Another technique for removing air is to give the pedal two or three quick strokes at the beginning. This pushes the air to a section of the line where it can be more easily bled by the usual, slooow, pedal depression method (which prevents air bubbles).
Funny, Atwell. :D

The 2 or 3 quick presses to start is a new thing to me. Might have to try that next time. Also, I didnt realize that going slowly with pedal presses is better than just flooring it pretty much right away. maybe that was part of our problem: Not enough clutch bleed foreplay. -eek- rotfl

Well, at least its set now. This is my second clutch master in two years but the last one we put on was probably a 25 year old NOS part. The rubber seals were likely on their way out when it was installed. I doubt Ill have the same problem. The slave was replaced last year and is good.

I can tell you this - Im a clutch hydraulics professional now - me and delomike can get ya in and out in less than an hour.... :)
 

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Now that you are good at bleeding the system you should do it annually so you do not forget how to do it. Don't forget the brakes too. A lot easier than replacing the hard parts when the brake fluid gets corrosive.
David Teitelbaum
 

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Discussion Starter #12
I bled about a quart of fluid through the system today, and the car is still stuck. Take a look at the pictures for an idea of how far the pushrod/fork is moving. I am pretty confident the system is totally bubble free.

I'm leaning even further towards it being an issue inside the transmission, but I'm still hoping someone can maybe point to something that I'm overlooking. Any ideas?
 

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I would second this method. It also helps to periodically remove the vacuum (you can leave everything attached), pump the clutch pedal firmly a number of times, then restore the vacuum. Do this a few times over an hour or two and you should have good results.

Brake guy here. Not familiar with your clutch reservoir but i have had good luck getting air out of brake systems by pulling a vacuum over the reservoir. Get your hands on a mighty-vac and i have used any number of things to cap the reservoir, a hockey puck with a hole in the center works well. Put the puck on top of the reservoir in place of the cap, a little brake fluid helps it seal and use the mighty-vac to pull a vacuum on the reservoir through the hole in the puck. You can leave it on as long as you want. The air in the system will propagate back to the reservoir and any microscopic air dispersed in the fluid will come out. Doesn't beat a normal bleed but usually gets that last bit of air you can't force out.

Sent from my MB860 using AutoGuide.Com Free App
 

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This would be even better than as mounted (slave horizontal), bleed nipple on top, yes?
No, the bleed nipple should be at the top uppermost point when bleeding, air rises to the top of the slave cylinder and is released out of the nipple.

Bleeding with the nipple to the side or at the bottom of the cylinder will just cause the trapped air to further airate the fluid.

If the clutch pedal feels spongy, there is still air in the system.

Bleed on brother.
 

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tap the cylinder with something hard just before opening bleed valve: releases the air bubbles clinging to the metal.

If pumping the clutch a few times before putting trans in gear works or helps, you still have air in lines.

I just use a hand vacuum pump and bleeder kit, both from Sears, and find it works beautifully.
 

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Wingless Wonder
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Looking at those rear brake rotors...pretty rusty.

Has the car been driven much? Is it possible that the clutch release splines (input shaft) are rusty and causing this symptom?
 

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Discussion Starter #17
I figure I'd better give everyone some closure...

I was finally able to get the thing working after picking up a mityvac, and generously applying teflon tape to all the threaded connections in the clutch hydraulic system. As much as I hate to admit everyone else was right, looks like the issue was just air in the system.

Interesting side note, I tried the stuck clutch procedure of starting the car in 2nd, then brakeing to unstick before the above. After push starting, the clutch seemed to be working ok as I drove around for a few minutes. After I stopped and idled for a few minutes, it was back to stuck. Wonder why it seemed to work after I got moving initially.

Anyway, thanks for all the input, and most importantly everying is working! For now.
 

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I figure I'd better give everyone some closure...

I was finally able to get the thing working after picking up a mityvac, and generously applying teflon tape to all the threaded connections in the clutch hydraulic system. As much as I hate to admit everyone else was right, looks like the issue was just air in the system.

Interesting side note, I tried the stuck clutch procedure of starting the car in 2nd, then brakeing to unstick before the above. After push starting, the clutch seemed to be working ok as I drove around for a few minutes. After I stopped and idled for a few minutes, it was back to stuck. Wonder why it seemed to work after I got moving initially.

Anyway, thanks for all the input, and most importantly everying is working! For now.
Great to hear. Ive found in my travels that clutch hydraulics on this car are quite finnicky and have zero tolerance for air or any other abnormality. Ive also found that once the master or slave starts to go, the other aint far behind. I recommend changing/bleeding out the clutch fluid every season too.
 

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Clutch Issue

We service a number of little driven Ferrari's and have encountered the same type of issue. It very well may be a bleeding issue but there is another possibility. Perhaps the disc is stuck to the flywheel. Even if the pressure plate is releasing the disc is turning with the flywheel not allowing you to shift the transmission.

Once you have determined there is enough movement to release the clutch, I would put the car in gear with the motor not running. Then depress the clutch and try and rock the car back and forth to see if its still locked up with the clutch pedal depressed. If it is the disc is stuck to the flywheel.

If so, there is a way to break it loose. roll the car out where you can start it in gear, once started push the clutch pedal down several times and that usually breaks the disc loose. We reccomend making a rod to depress the clutch pedal to the floor when leaving the car in storage for any length of time.

Ferrari guy:cool:
 

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I would add that the amount of tolerance at least for the UN1 transmission friction disc is very small. Don't ask me how I know, but using an aftermarket friction disc resulted in my having to remove the tranny a second time and replace it with the stock Valeo disc on my '89 Turbo. The difference? The Raybestos (sold as being a drop-in replacement for the OEM friction disk) measured at 8.6 mm. The valeo is about 8.1 mm. With the Raybestos I had enough clutch drag to make is impossible to get the car in reverse with the engine running (no synchro on reverse, can't have any clutch movement). I pulled out the trans (which I had just put in a few days before) put in the Valeo disc (from JAE) and the clutch behaved quite properly. Only 0.5 mm over stock is enough to cause a problem in the Esprit clutch. I am told that the OEM spec for the friction disc is 8.0 mm with a +/- of 0.1 mm.

Live and learn!

:sad:
 
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