TR2/3/3A TR3A clutch hydraulic problem

[mapleaf]

One last shot before I take it to a professional.
After having the clutch master cylinder sleeved and rebuilt and installing a new slave cylinder kit and bleeding the system numerous times I still can't get it working right. Here's what i have observed.
Initially no pedal resistance.
Pump the pedal 2 or 3 times and I get normal resistance and normal shifting.
Take my foot off the pedal and it loses complete resistance in a few seconds, but if I keep slight pressure on the pedal (at top end) it maintains normal resistance.
I have also noticed that when I depress the pedal, even when there is no resistance, the slave cylinder pushrod extends?? but probably not the full distance since it won't shift gears.
Any thoughts, ideas, tips, hints etc. will be greatly appreciated. TIA

 

[TR3driver]

Are you sure the slave cylinder is properly adjusted? Sounds a lot like the adjustment is way off (perhaps due to a broken taper pin).

 

[mapleaf]

Thanks Randall, at this point I don't even want to think that it could be a broken taper pin so I've checked the slave cylinder adjustment and it is the recommended 2mm. Just wondering if there is an adjustment for the M/C. that may be incorrect. I know from my manual there seems to be an adjustment for the Lockheed M/C and the earlier TR3s that have the bolts on the front of the M/C mounting bracket. Is this adjustment just for pedal height or does it affect the M/C operation?
I'm looking for any other possibilities or suggestions before I start to seriously consider tackling a broken taper pin job.
Thanks again.

 

[Geo Hahn]

Well, for what its worth, my TR3A clutch works fine so long as I do not have a return spring connected on the slave.

If I connect a spring it behaves more or less as you describe.

So, you might see what happens w/o that spring.

Yes, there is something wrong with mine (might be the clutch fork pin) but since it works for now I'll live with it.

 

[TR3driver]

The MC pushrod adjustment (on cars with front disc brakes) can be used to raise the pedal height a little. But it's important that there be some freeplay, so if you have the pedal stop adjustment (the bolts in the mounting bracket), it needs to be backed off to maintain at least the recommended .010" of freeplay.

Are you certain the piston was bottomed in the slave when you measured the 2mm ? The comment about the pushrod moving with no pedal resistance says there must be a problem in that area, since normally the pushrod will meet with firm resistance (supplied by the springs in the pressure plate) as soon as it has taken up the free play.

As a test, you might try adjusting out all of the free play at the slave and taking a brief test drive. I suspect that after the drive, you will find it loose again. (In any case, be sure to set it back to the recommended clearance before continuing to drive the car.)

 

[mapleaf]

Well, I think I found the problem and you were right Randall, it was related to the slave cylinder/pushrod/adjustment. Apparently the DCO installed the slave cylinder on the wrong side of the mounting bracket. Gotta take pictures. But in my own defence all my reference catalogs and manuals show it installed from the engine side.
Thanks guys

 

[TR3driver]

But in my own defence all my reference catalogs and manuals show it installed from the engine side.

Actually it is supposed to be on the engine side of the bracket.

BTW, you really should get a copy of "Practical Hints for the Maintenance of the Triumph TR3", preferably the edition that matches your car. It has a lot of that kind of information, that changed during production (and was never updated in the workshop manual).
Here's a copy of the 6th edition, suitable for cars after TS60,000
https://docs.google.com/file/d/0B2H...M2U2LWJhYWUtMjEyZDgxMzUyNzUw/edit?usp=sharing

I hope to get the others scanned eventually, but haven't made much progress recently.

 

[mapleaf]

Randall, thanks for the copy of Practical Hints, up until now I've been working off a hard copy of the 1st Edition which, as I am sure you know, was for the TR2. It will come in handy. Anyway, the clutch seem to be working fine now. so thanks again guys.

 

[luke44]

... Apparently the DCO installed the slave cylinder on the wrong side of the mounting bracket...

Nice to follow posts of stuff I have coming up. Dumb question. What's a DCO?

 

[HerronScott]

Darn Current Owner?

Scott