I don't claim to be an expert on the Tiger servo (mine has been sitting on
a shelf for 20 years, you can stop ok without it) but I doubt your problem
is caused by the vacuum piston sticking. If that was the problem it should
still stick after the engine is shut off. I think you have a problem in the
valve that controls the vacuum. The piston is probably still under vacuum
even though the pedal has been released. On a related subject, I suspect
that you may also have a faulty or missing vacuum check valve in the line
from the intake manifold. If there is no leakage the servo should not
loosse vacuum when the engine is shut off, though an air leak at the servo
could give the same symptom.
Doug Leithauser
----------
> From: Wayne Pierzga <w_pierzga@email.msn.com>
> To: tigers@autox.team.net
> Subject: Brake Servo Rebuild Questions
> Date: Saturday, February 28, 1998 8:23 PM
>
> Hi:
>
> I have rebuilt the brake servo on the Tiger I am restoring. It is the
model
> with the large drum. The rebuild kit included "special lubricant" to be
> applied to the leather gasket on the vacuum piston. There really was not
> much of this lubricant in the kit.
>
> I reassembled the servo and reinstalled it on the car and bled the
brakes.
> When I start the car and apply the brakes they stay on until I shut off
the
> engine. At this point the vacuum is released and the brakes disengage.
When
> I start the car the brakes remain off until I depress the brakes at which
> time they lock up again until the engine is off and the vacuum is
released.
>
> My suspicion is that the vacuum piston is not moving smoothly in the drum
-
> that the spring is not returning the piston to the end of its travel.
Hence
> the brakes stay on until the vacuum is removed.
>
> Can anyone suggest a simple fix for this problem? I am tempted just to
cycle
> the engine on/off until the piston moves smoothly (assuming that this is
the
> problem).
>
> If cycling the engine on/off does not solve the problem then I suspect
that
> I will take the drum front cover off and lubricate the piston. Can anyone
> suggest where I might find more "special lubricant"? (Or tell me what it
> is?)
>
> Many thanks,
>
> Wayne
>
>
>
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