[Healeys] troubleshooting rebuilt Girling BJ8 brake servo

[Bob Spidell]

I've had similar symptoms with a failed 'foot valve'--the little seal 
that lets fluid into the MC from the reservoir which should close when 
you apply pedal.

Bob


On 10/21/2015 2:02 PM, David Porter wrote:
> Call Tim or Martin at Power Brake in CA 408-292-01305 helpful folks..
> Dave
> GT6+
>
> On 10/21/2015 2:39 PM, Michael Salter wrote:
>> Hi Bob,
>> In my experience the Girling servo units can be very difficult to 
>> rebuild satisfactorily.
>> The symptoms that you describe are however more indicative of air in 
>> the system than those typical of servo difficulties.
>> If the servo is not working properly the typical symptoms are no 
>> servo action at all or brakes dragging and/or locking on.
>> To check the servo action pump the brake pedal several times with the 
>> engine not running then,  with pressure on the brake pedal, start the 
>> engine and the pedal should drop a little as manifold vacuum is 
>> established. If the pedal drops the servo is working.
>> The other problem is evident when you drive the car.. First the brake 
>> pedal will become quite "hard" and there will be no "free play" at 
>> the top of its stroke next the brakes will get very hot and 
>> eventually the car will stop moving because the brakes are locked on..
>> The usual cause of that problem is the failure of the large piston 
>> within the servo unit to return fully to its rest position when the 
>> brakes are released. That is where the "thinner sponge" thing comes 
>> in. The correct solution is to have the inside of the servo "chest" 
>> re-coated with a special slippery coating. There should be more 
>> information on that way back in the archives.
>> Hope that helps,
>>
>> Michael S
>> BN1 #174
>> (4 wheel drum brakes ..no servo)
>>
>>
>>
>> On Tue, Oct 20, 2015 at 6:24 PM, R. Cobb <rcobb at earthlink.net 
>> <mailto:rcobb at earthlink.net>> wrote:
>>
>>     Unit was rebuilt using kit from Moss.
>>
>>     Symptoms, following bleeding hydraulic brake system (no
>>     differences noted whether car running or not): On first try of
>>     brakes, nearly no braking, with pedal going almost to floor.
>>
>>     Second try, sometimes a release is felt in the pedal (with an
>>     associated, slight "pop" sound) with a bit more braking and less
>>     travel of pedal.  By the third try, the pedal travel seems more
>>     normal, and the braking is improved, though not up to the level
>>     expected.
>>
>>     The above pattern has been replicated numerous times, with the
>>     thinking that perhaps if something were binding, it would
>>     work-in. No such luck.
>>
>>     Any thoughts?
>>
>>     I recall that some months ago a contributor mentioned having had
>>     to install a thinner sponge rubber ring for under the piston
>>     seal...because of binding(?).  Could this be the issue?  Would
>>     this result in the behavior I'm experiencing?
>>
>>     Thanks in advance.
>>
>>     Bob
>>     _______________________________________________
>>     Support Team.Net http://www.team.net/donate.html
>>     Suggested annual donation  $12.75
>>     Archive: http://www.team.net/archive
>>     Forums: http://www.team.net/forums
>>
>>     Healeys at autox.team.net <mailto:Healeys at autox.team.net>
>>     http://autox.team.net/mailman/listinfo/healeys
>>
>>     Unsubscribe/Manage:
>>     http://autox.team.net/mailman/options/healeys/michaelsalter@gmail.com
>>
>>
>>
>>
>> -- 
>> /If you can't fix it with a hammer, you've got an electrical problem./
>>
>>
>>
>> _______________________________________________
>> Support Team.Nethttp://www.team.net/donate.html
>> Suggested annual donation  $12.75
>> Archive:http://www.team.net/archive
>> Forums:http://www.team.net/forums
>>
>> Healeys at autox.team.net
>> http://autox.team.net/mailman/listinfo/healeys
>>
>> Unsubscribe/Manage:http://autox.team.net/mailman/options/healeys/frogeye@porterscustom.com
>>
>
> -- 
> Dave Porter Porter Custom Bicycles 2909 Arno St. NE Albuquerque, NM 
> 87107 505-352-1378 Go HERE: my world www.porterbikes.com/
>
>
> _______________________________________________
> Support Team.Net http://www.team.net/donate.html
> Suggested annual donation  $12.75
> Archive: http://www.team.net/archive
> Forums: http://www.team.net/forums
>
> Healeys at autox.team.net
> http://autox.team.net/mailman/listinfo/healeys
>
> Unsubscribe/Manage: http://autox.team.net/mailman/options/healeys/bspidell@comcast.net
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20151021/20a7615f/attachment.html>