I was out for a drive yesterday ( 71 OTS 4.2 ) when quite suddenly the clutch pedal seemed much stiffer and as though it was not returning completely or was returning very slowly. I was still able to shift into all gears without grinding but I headed home directly. I found the reservoir to be full and no apparent leaks at the slave or master… I’m sure it would benefit from a fluid change as its not been renewed during my ownership (3 years)
Does this sound like any specific problem ? I’m going to get the car up on stands for a better look but any and all advice would be greatly appreciated.
Suspect everything, assume nothing. But among the things to look at are the presence of the return spring on the slave…
Through the hole in the bellhousing you can get eyes on the throw out bearing and watch its action:
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I wonder if the rubber hose is consticting? Or the metal tube got smashed by a rock???
Tom
Another possibility - the return spring on the clutch pedal itself has snapped - very common problem. It’s a pain to replace, so many folks just improvise with a bungee cord or the like.
The return of the clutch actuating mechanism is almost entirely controlled by the spring in the clutch assembly and it is very powerful. The external spring on the slave cylinder is more involved with returning the piston assembly in the slave back to a position so that the release bearing is no longer touching the release ring on the clutch, and wearing, this action occurring after the clutch is fully engaged Your description of a stiffer return is a bit baffling as it implies a failure of some kind in the clutch diaphragm spring, or the fork assembly pivot perhaps freezing up. The latter would add stiffness to depressing the clutch as well…
Could be the steel rod that acts as the pivot has slipped halfway out of position. Fairly easy to check since there is a hole it was inserted through in the bell housing. Unfortunately, if this is the case, I don’t see how one puts it back in place and secures it without removing the engine/transmission.
They do slip out. I had one go completely AWOL in the 2+2.
Sounds like the rubber flex hose has swelled internally causing a resstriction both ways. Harder to push in and slower to return as the fluid passage is restricted. Seen it numerous times. Seems to be hard to diagnose the first time.
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Yes - I had one fall out, but it remained in the bell housing where it struck the flywheel and was driven hard enough to put an inside out dent in the alum. bellhousing.
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There is no return spring or remanence of one, on my slave cylinder. Am I to assume it’s the hydrostatic type of slave? (engine is 7r 11732-9) Also, are industrial methylated spirits the same as denatured alcohol? My Haynes manual says to remove the master cylinder after flushing to pour off accumulated spirits. The Jaguar manual makes no mention of removing the master. is that step necessary?
by rubber flex hose do you mean the one from the slave to the master ?
Every so often and for reasons I have never been able to ascertain, even after a complete White Post rebuild, is the clutch would occasionally stiffen up and be just like a brake pedal. The only thing I could ever figure out how to do was to tap of my foot, and then it would reset.
Yes, there is only one rubber flex hose in the pressure side of the system
Different, depending. Denatured alcohol is ethanol with an additive that makes it undrinkable. Industrial methylated spirit is also denatured but, if I’m not mistaken, has more methanol in it, as well as other nasties like acetone Another name for methanol is methyl hydrate. You can buy it by the quart or gallon at Loews or Home Depot or any other place that sells paint supplies.
My money’s on the flex hose. And I think you should be installing a return spring on the slave.
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I finally got around to sorting this out. Hats off to all those who suggested the flex hose as the cause.
It was really badly constricted. while I was at it: new seals in master cylinder, flush all hard lines, clean reservoir, new hydrostatic slave, new flex line of course. The return spring on the pedal is broken, and even though I ordered a new one, it looks like a big project to replace so I rigged up a spring that works pretty well. What a huge difference in clutch feel. I’ve been stomping on that pedal since I’ve owned the car (3 years) and not realized the problem. It seems to downshift into second fine now as well. Cheers!
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Any tips on replacing the clutch flex line or is it pretty straight forward ? When I was replacing my slave cylinder a few years ago it looked like it might be an unpleasant job. I have replaced all my brake flex lines but have not tried the clutch flex line yet.
David
68 E-type FHC
The upper connection of the flex line was a beast. It’s really hard to get to even with every offset and stubby wrench you have. I removed the small vacuum advance and brake vacuum hose from the intake manifold. In retrospect I should have drained the coolant down and removed the heater hose as well. Once I got the compression fitting slackened, I could not not budge the hex nut that secures it to its small L bracket. It it wanted to twist this bracket it was attached to. Even with someone under the car with a wrench on the back. Unbolting the L clip would have been an option but the hard pipe was directly over it and there was not enough flex in the hard line to remove the bolt. I ended up very carefully carving the top of the flex line and its nut up with a Dremel. The spring steel lock washer under it prevented the Dremel from damaging the L bracket . Before you secure the new flex hose, check alignment to the compression fitting. I had to tweak the L bracket slightly ( because I had twisted it ) and its much easier to do before the new hose is secured. Good Luck!
An understatement if I ever did read one…
Your description is pretty much what I found, too. That’s why I, when engines were out, I automatically always replaced that line.