Mondial 3.2 QV Clutch Partial Engagement

I was a fine morning to take the Mondial out for a spin with a buddy and unfortunately ran into an issue I have not experienced before, the clutch, suddenly and without warning, seemed to be stuck in a position where it was only partially engaged. This happened at an intersection waiting for oncoming traffic to clear with clutch pedal fully depressed before turning left.

When the clutch was let out, the car barely crept forward and once through the intersection we pulled over and parked the car to investigate.

Clutch pedal felt normal, reservoir fluid levels normal and no sign of leaks under the vehicle. Could easily shift the car between gears but every time the pedal was let up to engage the clutch, only slight power was transmitted to the wheels and not enough to move it. Could also hear some slight rotational noise from inside the car but nothing that sounded catastrophic.

Let it cool for a bit, tried again but no joy. Called a neighbor and towed the car a short distance home. When home, tested the clutch again and low and behold, it worked normally.

My buddy suspects the throwout bearing. I agree in that the bearing itself is rotating as it should by somehow became bound between the bearing housing and transmission input guide sleeve.

Am I on the right track?

 

Year, mileage, export market? Give us some more information. No, I'm not going to search your profile to find out what car you have! Maybe we can tell you what it is if you provide more info. I think your clutch is probably worn out, either clutch disc itself or the throwout bearing, but without more information we don't know what to tell you!
Alden

 

My bad. US spec 86 3.2 QV w/49K mi. Flywheel resurfaced, clutch disk, pressure plate, release bearing replaced by previous owner at 35.3K.

Vehicle has not exhibited any usual signs of worn out clutch disk, ie clutch slippage. Tested for slippage after getting car home and it was gripping tight.

 

if your clutch discs and throw out bearing are new and not worn out or abused, you have a failure in the hydraulic system either in the master or the slave cylinder. That is not typical but may be related to heat degeneration or abuse.
Alden

 

Thanks Alden,

The clutch has never been abused in my ownership. So if I focus on hydraulics, as far as I know most failures there lead to clutches that do not disengage; air in lines, leaky seals and the like.

For the system to not fully engage, then something has to hang up, not allowing the throw-out bearing to fully retract.

In that scenario, it seems the likely culprit might be at the slave cylinder given that the pedal feel was unchanged before, during and after the episode.

Have you ever run across an instance where the slave or master for that matter were binding?

Brock

 

It's air in the lines. You have a big air pocket in there. Thoroughly bleed, not with a bleeder but with pedal compressions like old school and it will fix it guaranteed.
Alden

 

I will give it a try but I cannot follow the logic on how an air bubble impedes clutch engagement. Pressure from the clutch plate tines should easily overcome/compress any air in the system leading instead, to difficulty in clutch disengagement. Cheap and easy to do and can't hurt so we shall see.

 

I had an issue with the slave cylinder. I replaced it, bled the system old school method and was back on the road.

 

Air is way too compressible, that is the problem with an air bubble.
Alden

 

Thanks Alden, you are 100% correct and I agree on the compressibility of air vs liquids being the root of most malfunctions in clutch hydraulic systems. When pressing the clutch pedal with hydraulics containing large bubbles, essentially the work performed goes into compressing the gas thus there is not enough pedal travel to build up the pressure needed to move the slave piston/clutch fork/throw-out bearing/pressure plate to disengage the clutch. And yes, most of that energy goes into compressing the clutch plate tines to unclamp the clutch disk.

I guess I haven't adequately explained what happened in my car because clutch disengagement was not the issue, I could freely shift gears yet no engine power was transferred. So in my case the malfunction was the opposite to that encountered with an air bubble, the clutch was not engaging as evidenced by lack of power to the wheels. That implies that something in the clutch mechanism was bound up, preventing the pressure plate from moving back to a relaxed position clamping the clutch disk to the flywheel.

My premise maintains, that in the absence of binding, there is sufficient force behind the compressed pressure plate tines to force hydraulic fluid, with or without air bubbles, back to the engaged position after the clutch pedal is released.

After towing the car home, the problem completely disappeared and works as normal. FYI, I did bleed the clutch hydraulics yesterday with no discernible change. I am still scratching my head and need a plausible explanation to correct the malfunction before I can ever trust the car on the road again. It sounds like I have a winter project ahead of me to R&R the clutch.

 

Maybe this will give you some not so obvious possibilities to check. My thought is mechanical, probably pressure plate or linkage issue.

http://www.mymondial32.nl/

 

Thanks David, exactly what I was thinking, I just couldn't rationalize where or what could be hanging the system up, let alone allow it to return to normal after being towed. The only way I will be able to trust taking the car out for drives in the future is to have comfort in knowing the cause and that it has been corrected. My plan now is to pull the housing and give everything a good inspection. And because I have it apart, will go ahead and plan on replacing all of the wear bits.

I am just fortunate that it happened relatively close to home. The original plan was to take an extended loop but Aspen leaf peeping traffic was building fast at 7am so we decided to truncate the route.

Great info on your link, thanks for sharing!

 

I don’t have a 3.2, but it looks like there is an external clevis from the slave. Before you disassemble, it might be good to start by checking how much yours moves vs one that works. Maybe it hangs up then pops back later. Work your way inside the housing, lever arm, etc.

 

Yes, there is an external clevis and had the thought yesterday while inspecting the slave that it might be a good idea to remove it and see if it was operating smoothly. But my time on a neighbor's lift was limited and the slave was bone dry so I put that nugget in the memory banks for a snowy weekend.

Good plan to work from the outside in as it looks like doing the full clutch job is going to be an unpleasant undertaking.