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Triumph TR6 - Clutch slave

OK...here's a new one for ya. I replaced my clutch slave and it was a bitch to get bled. Replaced it just like the old one. I was just on another BBS and they were all saying that a lot of new clutch slaves come packaged wrong and that the bleed nipple should be on top, not the bottom. Always. Went out and checked my car, and sure enough it was on the bottom. The shop manual shows that it should be on top also. Any thoughts? I figure the two fittings should be interchangable.
RF Ickrath

If you were an bit of air in hydraulic cylinder, would hang out toward the bottom of the cylinder below the fluid or toward the top of the cylinder atop the fluid?

The bleeder goes to the top where the bit of air is hanging out.
SteveP1

Well, if everything was based on common sense, refrigerator motors would be on top! But point well taken.....guess I have to move everything around...
RF Ickrath

There were some early refrigerators that had compressors on top (Kelvinator for example) but it's just such a fundamentally different closed system from the hydraulic one that component placement is optional as long as you stay within the realm of the desired attributes (keeping the cold stuff cold). Going back to early refrigerators again, the contemporary Frigidaire models to those early Kelvinators used low mounted compressors (as far as I know). I love that name and can see why it was used, it does sound much better than "Rankineator."

Our simple hydraulic system doesn't involve any phase changes, just fluid/pressure/volume relationships, so gravity plays a more critical role in eliminating the air in the system. Of course there's always the option of a "reverse bleed." We were being driven crazy by a friends Land Rover one day so finally threw in the towel on conventional means and dropped the bleed hose into a container filled with fresh brake fluid and opened the bleed valve. From there we pulled a partial vacuum on the clutch master through a modified cap until fluid appeared without bubbles. Shut off the bleed valve and we were good to go after a bit of clean up.
SteveP1

Steve....so you remember what you used to create the partial vacuum at the modified cap? I just tried using the method on line of using an oil can filled with brake fluid to push fluid from the bleed nipple up to the master cylinder. Seemed to work but still no clutch. I think one of the main problems is that the slave is mounted on a slant....tilted so the bleed nipple is not truly on top. Hence, there is almost no way of getting that last bit of air out. I am starting to think that I could pre-load the slave cylinder and install it. Getting tired of jacking the car up and down though with no positive results.....especially since the weather is perfect right now for cruising.
RF Ickrath

Hi Bob

Are you sure your clutch master cylinder is OK?

If there is a bit of air in the slave you should still find that if you pump many times without stopping the air compresses and the clutch should disengage. Not what you want permanently but you should still be able get it to disengage. If it doesn't I suspect there is something else going on.

I don't recall the whole history of your problem. Was your car sitting for a while? I have had experience where the clutch plate was rusted to the flywheel and nothing freed it until we pulled the transmission off. (not a TR6 but a Tr3)

Can you mechanically move the clutch actuator with a extension bar? And does that disengage the clutch? If it can't be done mechanically , it won't work hydraulically.

How about the thrust movement on the crankshaft? Too much thrust movement (back and forth) and the clutch won't disengage - it just pushes the crank shaft forward. I had that issue with my Spitfire when a thrust washer fell out.

I have never had as much a problem with bleeding the clutch system as you seem to be having so I suspect there is another issue. . I had a problem with the slave cylinder after a rebuild and the cylinder bore had corroded too much and it wasn't sealing- replacement was needed. I had the ring on the clutch master cylinder (that retains the piston rod that attaches to the clutch pedal come off and the piston of the master cylinder almost pop out inside the car. That happened at a stop light and imagine my surprise when the clutch just quit working and I couldn't move the car - had to push it off to the side.
Michael Petryschuk

I bench bleed and pre-fill everything hydraulic. Messy, but I don't mind wasting hyd fluid for ease in bleed and use.
J.T. White

That was about ten years ago or more, hopefully I've got it covered memory wise.

We rigged up a system using stuff we had sitting around the shop. A small electric vacuum pump with a ball valve as a "bleed" to control how much vacuum was pulled on a tee between a quart thick plastic container with a screw on lid. A quick disconnect pair was fitted to the lid and to a hose running toward the tee. A second tube was inserted into the jug through the lid down to the bottom of the jug and sealed with a grommet. At the other end of that hose we had another quick disconnect pair attached to an old master cylinder cap and small extension on it so the fluid level would hopefully not overflow the master cylinder when we removed the cap. We had another container, this one open at the top, on the floor near the slave cylinder with a tube running from the bleed valve to it, with that tube looped at the bottom of the container to make sure it stayed at the bottom and under the fluid since it would be an intake.

We filled the lower container about half way with brake fluid and opened the bleed valve, then flipped on the pump and let it pull fluid up through the system. I seem to recall that we closed the bleed valve and shut down the pump once or twice and let things sit for a couple of minutes, then repeated the process. We stopped seeing bubbles in the top container and decided we were finished. I don't recall how much vacuum was pulled, but it was anywhere near what we would have considered a hard vacuum, just a few inches probably. definitely single digit type numbers.

What can I say, it was three guys with engineering degrees, two that were working as engineers and one as a pilot. Sometimes we just decided to do things because thought it be "interesting" and we had stuff on hand to have a go at it.
SteveP1

Thanks Steve....I think that is above my paygrade though. I am starting to think that after I replaced the slave cylinder, it was so strong that the master cylinder failed next. Some folks suggest replacing/rebuilding both at the same time, since the parts wear at the same rate. The clutch had been fine up to that point when I replaced the slave, so I doubt if is the clutch itself. Just have to double clutch down shifting since the tranny is original. One of these days I will invest in a 5 speed. There is a place in town that will do it...though they recommend staying will all Triumph parts. I think my plan is to win Powerball first though. In the mean time I bought a rebuild kit from Moss for the master cylinder. The difference in price for a new slave and a rebuild kit was insignificant, but since I have a Girling master in the car, the $12 for a rebuild kit is the way to go.
RF Ickrath

And speaking of the rebuild kit from Moss? I ordered it two hours ago, UPS Ground Preferred? I just got an e-mail from UPS saying it is scheduled for delivery tomorrow! Is this a great country or what?
RF Ickrath

This thread was discussed between 02/09/2014 and 09/10/2014

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