T-Series Where did my clutch fluid go...

[srmorse]

Uh oh...

Went for my first spring visit to the MGB to do do a bunch of tune-up things.

First thing I noticed was the clutch pedal felt awful strange...and after starting, it was clear that there was no clutch at all. I opened the master cylinder and there seems to be no fluid at all in it...although the cylinder itself looks pretty much brand new. There was another car on the lift, so I couldn't get a good look underneath, but there was no spot on the ground under the car. It's been kept in heated storage all winter, and the clutch was fine when I parked it in November.

I just bought the car last September and have a bunch of receipts. None mention the master (which looks new), but there was a replacement of the slave hose almost 2 years ago. My first guess is the slave is shot...but why don't I see a puddle?

If it is likely the slave, should I attempt to rebuild it, or is it generally better to replace it?

 

[Guest]

they are cheap replace it, but if you don't see fluid, it's probably the master cylinder, check the floorboards around the driver's feet

 

[urchin]

I once had a Triumph Spitfire which sat for a winter. When I went to move it, the clutch master was empty. The fluid can evaporate and unused clutch rubbers can harden and let air in to complete the evaporation. I filled it, bled it, and eventually had a clutch action restored. The moral is not to let the car sit. I drove my Spitfire and my MGB year round and they benefited from it.

Jeff Aronson
Vinalhaven, ME

 

[SteveT]

I have the same problem with my brake master. The rear reservoir is completely dry with no signs of leakage. There is nothing on the floor of the car or the floor of the garage; the only other place might be the rear drums? But there are no puddles around any of the wheels or anywhere in the garage. Can hydraulic fluid evaporate?

 

[Fox]

I've never heard of it eveaporating, but maybe it can? i think you should first try bleeding the system to remove any air (hardened rubber seals will let air in over time) then you will see what will happen, if it will drip out or not!

 

[Dave Russell]

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Fox:
I've never heard of it evaporating, but maybe it can? <hr></blockquote>
In the experiment I tried, fluid sitting for a long time in an open container, it didn't evaporate but actually gained some volume from moisture pick up.
D

 

[srmorse]

Well...got back up to work on the car and topped up fluid and pumped the pedal several times just for ha-has to see if I'd get any pedal. Still nothing, so while I was working on replacing the fiber washers on the fuel pump (a leak there as well) I noticed brake fluid collecting on the outside of the slave cylinder. I pulled the slave and inside was pretty pitted and the internal seal had completely disintegrated. The push rod was also very badly scored, so although I had a replacement slave cylinder, I dodn't replace it as of yet until I get another push rod.

Hopefully that will do it...I'll give an update when I find out...

 

[srmorse]

well...got the replacement pushrod and put everything back together. Bled the system and I had clutch again! Unfortunately I couldn't take it for a test ride to be sure all was OK (entrance was blocked). But I was able to get into all gears and everything felt better.

Next time I'll get there will be a week or so...so I'll keep my fingers crossed and see if I still have pressure when I get back...