Advice and recommendations - clutch stuck

[lancsman]

I would appreciate some advice and guidance from the mechanically minded TR7 owner who may have encountered this problem before.

My TR7 has had an enforced garage "layover" but I now want to move it and proceed to MOT.

However, the clutch pedal was solid and wouldn't move so I assumed the slave cylinder had seen better days and possibly seized.

Unfortunately, before I could stop him, a big booted friend jumped in the car and stomped on the clutch pedal resulting in it moving to the floor and staying there!!!!!

My question is "what is the probable diagnosis and recommended course of action"?

I'm assuming the clutch plate is probably as one with the flywheel anyway but if I can get a functioning clutch pedal then maybe I can free this off using some perseverance and a warm engine.

I have a replacement clutch slave cylinder already so does the panel think a simple replacement and bleeding will restore the pedal? Are there any pitfalls to be wary of when swapping the slave unit?

All advice gratefully received.

Thanks.

Lancsman

[Dave Dyer]

Hi Lancsman,

My money would be on the clutch Master cylinder being jammed (is there fluid in there), you could crack the hose, if the pedal stays where it is its the master, but if it returns it could be the slave.

Dave

[Hasbeen]

First go to the workshop manual section Lancsman, & read Mildred's excellent instructions for overhauling, plus R&R the slave cylinder. It is essential to not disturb that pushrod when removing it.

Have you found any fluid under the car? The plastic pipe from the master to slave cylinders can fail.

I also think the rubbers may have been displaced in the master cylinder by your friend. It is exactly like any other master cylinder to overhaul. No special problems to be avoided.

The clutch plates do stick to the flywheel on occasions. There have been a few threads describing different members method of freeing them. I suggest you try the search facility. It often takes a couple or more goes to get to threads which are back in time.

There is another more nasty possibility. The clutch fork pivot has a tendency to wear through the fork. Every 7 I have owned with 100,000 kilometers had already been repaired & strengthened in that area, so must have failed.

This can give your symptoms, or have the pedal operate normally, but have no effect at the clutch.

Personally I'd start at the master. Good luck, & please report your findings.

Hasbeen

[busheytrader]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Hasbeen</i>




There is another more nasty possibility. The clutch fork pivot has a tendency to wear through the fork. Every 7 I have owned with 100,000 kilometers had already been repaired & strengthened in that area, so must have failed.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

When this happened to me at 60,000miles the clutch pedal went down to the floor, returned back up and then went solid. On that basis I' d check the master cylinder first as per the other learned advice here. It's quite easy to remove and recondition it yourself. The kits are cheap compared to a new or recon one.

Replacing the fork was an engine and gearbox out job for me. 2.0L engine went out and V8 replaced it. [:D]





TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, S/S Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes all round, Anti- Dive, Strut-Top Roller Bearings, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 14" 5 Spokes or Maestro Turbo 15" Alloys, Cruise Lights, S/S Heater Pipes, Replacement Fuel Tank. No Door Stickers. Mine since July 1986, V8 from 1991 courtesy of S&S V8 conversion kit (built not bought) and big brake kit.

[FI Spyder]

If you are going to rebuild the master and slave cylinders (not a bad idea any ways) I would spend a few extra bucks and get a brand name kit.

Example of probably good (considering source) but brand X kit

http://www.bpnorthwest.com/triumph/tr7-tr8/brakes/brake-master-cylinder-kit-mgb-75-to-80-tr7-tr8-2027.html

Example of brand name kit (TRW), the one I used:

http://www.bpnorthwest.com/triumph/tr7-tr8/brakes/brake-master-cylinder-kit-mgb-75-to-80-tr7-tr8.html

My first thought was the pivot through the clutch fork but hope not. When I replaced my clutch at 100,000 miles there was only a little wear at the pivot point so I left the fork in. The pivot isn't round at the end but has a cicular indent with sharp corners. Don't know why but seemed all the better to dig into the fork. I took a Dremel and rounded those sharp corners off a bit, greased it an put back in. I think I used my clear synthetic grease but if I did it again I would use my grey brake grease, heavy and designed not to migrate in hot conditions, important in rear drums but also important in clutch area.

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[lancsman]

Thanks for the suggestions so far.

I'll set aside some time in the next couple of weeks and let you know what I find.

Lancsman

[Cobber]

My money is on the pivot having punched it's way through the fork!

"Keep calm, relax, focus on the problem & PULL THE BLOODY TRIGGER"

80'Triumph TR7, 73'Land Rover (Ford 351. V8),
'89 Ford Fairlane
'98 MG-F, 69'Ford F250.

[busheytrader]

Impetuous big booted friends aren't allowed near my cars anymore.........

Probably because they're near the top of the hydraulic system and the rubbers are more likely to be oxidised, I've gone through a number of m/cylinder rebuild kits or even whole units when available cheap on eBay over the years. The slave cylinder is still original and untouched. I keep waiting for it to fail buy it hasn't so far. Both master and slave are relatively easy to remove and refurbish.

Replacing the clutch fork is another matter. If removing the slave cylinder be careful not to dislodge the pushrod that clips on to the clutch fork. The clip is fairly brittle and if that breaks then it's an engine and gearbox out job to rectify it, unless you're cleverer than me (most are [:)])

Good luck,

Adam

[Workshop Help]

Oh, Dearie, just take the car back to the dealer and he'll fix it under the warranty.

What's that you say, Abner? We IS the warranty now? Well, never mind.

Mildred Hargis

[whitenviro]

A picture is worth a thousand words:
[/URL]


[/img]
1980 Pageant Blue DHC with removable hardtop.

[FI Spyder]

Indeed it is. You can see the indent in the pivot, all the better to gouge out metal on the arm. I don't for the life of me figure out why they didn't just make it round. It's that circular edge I took the Dremel to.

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[busheytrader]

That picture took me back a few years.....

When I replaced the fulcrum pin for my V8 conversion it was machined from solid and didn't have the ridge as per the photo.