Mysterious clutch fluid loss

[DaveatMoon]

I have a '75 TR6 that was "restored" about 10 years ago. I bought it in 2006. It's weekend driver at best, but most of the mechanicals were redone, some better than others.

This winter around Feb. I noticed that all clutch fluid had suddenly leaked out of it. It was full when I put the car away, and functioned OK in Nov. and Jan. I'm just now getting around to fixing it.

In pulling the clutch hose I noticed that the hose was not very tight to the slave cylinder. It was beyond finger tight, but not by much. The slave cylinder looks to be brand new. The (red plastic type) hose had no obvious failures, but it, the pipe, and the master cylinder look to be original to the car.

My question is this, how can a clutch function with a likely too loose hose connection for a few years, and then suddenly loose <span style="font-weight: bold">ALL</span> it's fluid at once sitting for weeks on end in a cool (45 degree) garage? Or, can an apparently new slave cylinder be defective and lose the fluid itself in this manner?

Thanks for any insights you can give!

 

[TR4nut]

Dave-

Not sure how it can happen, but I can confirm that the fluid can leak out the slave cylinder - happened to me after changing the clutch on my TR4 and I apparently disturbed the cylinder too much. I'm not sure it is spontaneous, you might develop a slight leak in the seal, then over time it just drips out.

Randy

 

[frankenstang57]

Same thing happened to my Herald. I got it running in Sept. and had no clutch fluid in Dec. Then again, the hydrolics need to be rebuilt. My guess is the slave cylinder in both cases. Was yours new 10 years ago? Alot can go south on a car that is not driven regularly...

 

[Geo Hahn]

...My question is this, how can a clutch function with a likely too loose hose connection for a few years, and then suddenly loose <span style="font-weight: bold">ALL</span> it's fluid at once...

Little dudes came in and loosened it. Same guys who put fingerprints all over your eyeglasses when you set them down or hide your car keys from you.

 

[Tabcon]

Are the clutch hydraulics boosted in any way, like with a brake booster?

I had this happen once with my AH 3000, but with the brakes. The booster uses the vacuum from the intake manifold and because the seals in the booster were worn out, the intake was sucking all the fluid into the intake. It happened slowly at first, then more quickly as the seals got worse.

 

[Moseso]

You're gettin' weird, Geo...

I have never encountered a "mysterious" hydraulic fluid loss. It's always been readily apparent to me just exactly where the stuff is getting out. It's VERY messy stuff!

Rebuilding a clutch slave is a quick, easy and inexpensive job. If in the least doubt, just do it.

 

[Keoke]

Did you hear what that fellow Tabcon said above ?? He knows of what he speaks and it is pretty common knowledge among LBC owners with boosted breaks..__Keoke

 

[TR3driver]

Mysterious leaks into the brake booster are all too common on cars with a brake booster.

But there's no booster on the clutch. A leaking slave will generally leave a noticeable puddle on the floor or driveway; but I have seen people not notice that their carpets are soaked from a leaking MC.

 

[DaveatMoon]

Thanks for everyone's help. TRF has all of their clutch stuff on sale through today so I'm just going to replace the whole system to be sure.

There is a puddle under the car in a drip pan I had for small oil leaks. It's oddly located several inches away from the line, which is bone dry throughout, so it must have been running along the underside of the tranny. Also the driver's floor is bone dry as well, so I'm pretty sure it was either the slave cylinder or the connectio to it.

At any rate it had DOT5 fluid in it, so paint is not an issue. And yes, there is no booster on a TR6 clutch.

 

[frankenstang57]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]There is a puddle under the car in a drip pan I had for small oil leaks.[/QUOTE]

Mine must have been attacked by a brakfluidacabra, no puddles, just dry. Time to set the traps...