Clutch Sticks

[Penni]

The clutch on my 58' TR3 A is sticking... today I pushed in the clutch peddle and it stuck down. Car won't go into gear.
Think I should check the clutch fluid? Okay... where do I look for it ? Also, if I put more in, do I bleed it or will it bleed itself from use?
You guys know everything !
Thanks, Penni

 

[TR3driver]

Sounds to me like you have multiple problems. Even with no fluid (and therefore no force from the clutch or the return spring on the slave), the pedal should still return to the top. That probably indicates that the pedal pivot is binding. Normally the pivot only requires a drop of oil every blue moon or so, but if it is binding that badly, I would want to disassemble, clean and lubricate it.

The fluid is in a can near the wiper motor (under the hood/bonnet), item B in the photo below. Since the clutch shares the fluid reservoir with the brakes, it is something you want to check rather more often. There is a divider so that, in theory, a leak in the clutch cannot disable the brakes, but it is still a good thing to keep track of.

 

[Penni]

Thank you so much for this information. Especially the photograph.

 

[Member 10617]

Penni,

Randall is no doubt correct that your problem is not with the clutch fluid. But while we're on the topic, here's a few things to remember when checking and topping off the clutch/brake fluid. (1) The top of the can, because of corrosion, is sometimes very difficult to remove, so work at it carefully. (2) Check the fluid level. Don't overfill. And don't leave the top off too long as air will contaminate the fluid (so I am told). (3) Don't spill any fluid on the paint in your engine compartment because it will remove the paint very quickly.

If the fluid needs topping off, pour it in slowly so as to avoid bubbles. If the can is not empty (dry), you won't have to bleed the brakes or clutch. And be sure to use the correct fluid.

These are all lessons I had to learn when I started driving my car.

You might also check the return springs for the clutch: one under the car and one attached to the clutch pedal in the driver's compartment.

 

[TR3driver]

And don't leave the top off too long as air will contaminate the fluid (so I am told).

It's true that if you use conventional (DOT 3/4/5.1) brake fluid, air will contaminate the fluid over time (the fluid absorbs moisture from the air), but leaving the cap off doesn't make much difference. Newer cars have a barrier built into the cap, but the TR3 does not. As a result, conventional brake fluid should be changed every few years. Also, you should always discard a can of new brake fluid once it has been opened (the deterioration process starts as soon as you break the seal on the can).

Some people (myself included) prefer to use DOT 5 "silicone" brake fluid, which does not absorb moisture, will not attack paint, and does not need to be changed so often. In my experience it also helps the other brake components last longer. It was originally developed for the US military, who wanted to be able to store vehicles unattended for long periods of time and have them ready to go on a moments notice. It does have some disadvantages though, so it's not for everyone. Some of the disadvantages are that none of the brake component manufacturers "approve" of it, it is slightly more compressible (meaning you get a somewhat softer pedal), and it is both expensive and hard to find. (Although the last two aren't too bad if you buy in quarts from Roadster Factory.)

I'm not trying to reopen the brake fluid wars, just make Penni aware of the tradeoffs.

BTW, that photo is from "Practical Hints for the Maintenance of the Triumph T.R.3", which was basically the factory owner's manual, PN 501528. It is a very good reference to have, IMO, as it has more up-to-date information than the workshop manual does. The 4th edition would be most appropriate for your car (TR3A up to about TS50,000), but unfortunately all I have at the moment is the 6th edition https://docs.google.com/open?id=0B2H2NJt34OffNjQ4MTkyNjItZTVmYi00M2U2LWJhYWUtMjEyZDgxMzUyNzUw

But 4th editions do occasionally show up on eBay. Here is a 5th edition, going for what I consider a reasonable price (considering condition):
https://www.ebay.com/itm/c1959-Main...h=item564fef3dfe&ssPageName=RSS:B:SHOP:US:101

 

[Penni]

This Maintenance book is amazing. I hope to print it out. Thanks so much

 

[Member 10617]

Randall,

Whenever you post something, I learn something new. Many thanks.

I had heard that brake/clutch fluid should be changed periodically, but I didn't realize that it should be changed "every few years." I assume you are recommending about every two years.

So here is the question: As a half-way measure, am I safe in removing "most" of the fluid from the reservoir -- not so much that I would have to bleed the entire system -- and refill or "top-off" the fluid level? I know that doesn't refresh what is in brake lines, but it may mix new with old.

I have Valvoline Synthetic DOT 3 & 4 Brake Fluid currently in my system (installed about 12 months ago). When it is time to replace or refresh, I am planning to use Castrol GTLMA Synthetic Brake Fluid, DOT 3 & 4 -- recommended by Moss and purchased from them. Any problem in mixing the two?

MOSS sells Silicone Brake Fluid. I assume it is DOT 5, but the catalog doesn't say.

And finally, if I open a container of brake fluid and use some but replace the cap immediately, is it really necessary to dispose of the unused fluid? The amount of air in the container is going to be pretty small. I don't mind disposing of the unused fluid, but wonder just how necessary this is. The instructions on the container say: ""Keep container clean and tightly closed to prevent absorption of moisture."

 

[Marvin Gruber]

Another clutch sticking issue that is quite common is the hyd hose to the slave cly has swollen and not letting the fluid return. If your hose is old I recommend changing it out as well.

Marv

 

[TR3driver]

Good point, Marv. But it still shouldn't keep the pedal from coming up.

Ed, I'm not really "recommending" anything, just repeating information from other sources. I switched to DOT 5 a long time ago, and I don't bother changing it at all (until something else goes wrong, of course). But GM, for example, recommends changing DOT 3 fluid every 2 years. I'm sure that is very conservative, probably it can be extended a long time without ever seeing a problem, especially for someone that drives as conservatively as you do.

The thing is, the absorbed moisture lowers the boiling point of the fluid. If caliper pistons ever do get hot enough to boil the fluid, chances are good that you won't live to make the mistake again, as the result is sudden, total failure of the hydraulic brake system. And the handbrake, while certainly better than nothing, does a very poor job of stopping the car from high speeds.

There was a paper presented to the SAE many years ago (by GE, who may not have been entirely impartial as they used to make DOT 5 and the paper was pushing the advantages of DOT 5), that claimed they found "real world" cars with water contents as high as 6.7% after just 23 months of operation. That is enough to lower the boiling point to just slightly above that of plain water (260F according to the SAE standard test method).

The old brake fluid also seems to become rather conductive and corrosive, a particular problem in the clutch slave and rear brake cylinders, which are aluminum housings with steel pistons. That same SAE paper reported finding salt in the brake fluid of 65% of the tested vehicles, and showed how both water and salt can be absorbed right through the brake lines.

Also, FWIW, once upon a time I bought a pair of new rear brake cylinders and for reasons I can't quite explain, decided to fill them with Castrol brake fluid and store them that way (using bolts to block the fitting). Several years went by, and when I finally tried to use them, I found that they were corroded beyond even rebuilding. I don't have a photo of them (didn't own a camera at all back then, let alone a digital one), but here is a more recent photo of a clutch slave showing similar damage:

Anyway, what I'm trying to say; if I were only going to do a partial change, then I would want to change what was in the cylinders rather than what is in the reservoir. Just bleed at each corner until what you get out looks like clean, fresh fluid; then top up the reservoir and bleed the next corner.

 

[Member 10617]

Randall,

Understood.... As usual, you have provided very useful information. I'll stick with DOT 3 & 4, just because that's what I have been using, but if and when I "refresh" the fluid, I'll bleed the system and run fresh fluding throughout, as you recommend.

But, now, these questions: (1) Is it enough to just bleed the fluid from the brakes, or do I have to do something with the clutch as well?
(2) When you say "bleed the corners," I assume you are referring to each the brake lines at each wheel .... just want to make sure I understand.

You are right about my driving conservatively. A couple of months ago, I was in line with some other car club cars and we were heading down the mountain from the Blue Ridge Parkway. When we got to the bottom, the fellow in the car behind me (a new car) said that my brake lights didn't seem to be working because he never saw them come on as we went down a very steep road with many hairpin turns. I told him that they were working fine... I just didn't use my brakes. Went down in third gear... at times in second gear... never more than 20-25 mph. Can't do that in most modern cars!

 

[TR3driver]

But, now, these questions: (1) Is it enough to just bleed the fluid from the brakes, or do I have to do something with the clutch as well?

I would, to avoid the kind of damage pictured above. But you don't "have" to, many people simply ignore the problem and replace the slave cylinder when it gets pitted beyond use.

(2) When you say "bleed the corners," I assume you are referring to each the brake lines at each wheel .... just want to make sure I understand.

You understand just fine.

 

[Member 10617]

Many thanks, Randall. Sage advice, as usual.

 

[Penni]

And the answer is: My mechanic put in a new master cylinder.
Just wanted to let you know.
Thanks for all the answers. Cheers. Penni