Hi all, I just started the restoration of my 68 FHC and am now in the disassembly process. As I removed the vacuum tank I noticed it was full of some kind of liquid. Drained some of it and it is sort of oily. Is this normal? I didn't think there was supposed to be any fluid in it. Any idea where this fluid could have come from?
All input is appreciated.
Thanks,
Bill.

 

likely brake fluid. Should not be there.

 

Hi Alfred,
Thanks for your input. Brake fluid does make some sense since the vacuum tank is part of the system to assist the brakes. But how in the world did the brake fluid get in the tank. As I recall, the hoses that are attached to the tank are connected to the intake manifold and to the brake booster. However, as far as I can tell there isn't any brake fluid in the booster. Or is there?
Thanks,
Bill.

 

A while back I was loosing brake fluid. I was told to check the pressure tank and if there was brake fluid in there then it was coming through the booster. Bad seals were the suspects.

 

OK Alfred, thanks. I did not think that there was a connection. The brake booster is coming out next. Will definitely take a look at rebuilding it if it is possible.
Thanks again for the information.
Bill.

 

Hi Bill,
I'm in the middle of a major brake overhaul on my '66 E coupe and I also found the vacuum tank about half full of brake fluid. So at least you are not alone with these problems. We should keep in touch and compare notes.
As Alfred said earlier in this thread, defective seals in the booster are the likely cause for fluid to make it all the way to the vacuum tank. After i removed the servo from the car approx. 3/4 of a pint of brake fluid drained out of the servo outlet ports. so be ready !
Good luck
Charlie

 

If you have a look on any supplier website that shows the Jaguar parts diagrams, (such as SNG Barrett), you'll see the seals that separate the vacuum chamber from the slave cylinder in the booster. I believe there are rebuild kits available, or service exchange boosters

 

Thanks Charlie and Fraser.
It is good to know that I am not alone in this discovery. I really didn't know that there was a way for brake fluid to get into the vacuum tank. I will take a look at a parts catalog as Fraser suggested so I can better understand the connection.
Thanks again for the input guys.
Bill.