Jump to content

Remote Brake Servo problems


Recommended Posts

Has anyone got experience of the aftermarket remote servo kits being sold? I've had two now, brand new, having exchanged one as faulty. Neither work properly, with variable braking and also with brakes remaining on after pedal pressure has been removed, random duration, but for as long as a couple of seconds sometimes... rather disconcerting when you're braking into a corner at speed! And the latest one i've had is practically non-existent when straight out the garage, improving after it's been pumped a few times. A local mechanic here reckons it is the piston sticking or something similar, not a bleeding issue. But I'm about to give up and chuck the lot in the bin. Does anybody have any views or advice? unfortunately the unit is out of the warranty period as I took a long time to put it on. Thanks! Frank

Link to post
Share on other sites

Has anyone got experience of the aftermarket remote servo kits being sold? I've had two now, brand new, having exchanged one as faulty. Neither work properly, with variable braking and also with brakes remaining on after pedal pressure has been removed, random duration, but for as long as a couple of seconds sometimes... rather disconcerting when you're braking into a corner at speed! And the latest one i've had is practically non-existent when straight out the garage, improving after it's been pumped a few times. A local mechanic here reckons it is the piston sticking or something similar, not a bleeding issue. But I'm about to give up and chuck the lot in the bin. Does anybody have any views or advice? unfortunately the unit is out of the warranty period as I took a long time to put it on. Thanks! Frank

Frank have you asked the manufacturer for advice, they should be able to isolate your problem.
Link to post
Share on other sites

I had this problem with a Lockheed-6 type servo with silicone brake fluid - really annoying!

 

When I had a Mot-a-Vac unit rebuilt, the internal seals were coated with "Molycote" silicone O-ring grease (as advised by servo guru Paul Norton), and all has been well for over 5 years (still using silicone fluid).

 

Adey

PS: if you need a servo rebuild, there's a place in Castleton near Rochdale that did mine. J&L Exports I think they're called.

Link to post
Share on other sites

Many moons ago I was eyeing up a natty little servo on a GT6 with a view to 'improving' the TR4A brakes.

 

Ian Cornish came along and asked if I was able to lock up the brakes. 'Yes' I said.

'Then why do you need a servo' says he.

Did I detect a slight smuggness there, perhaps not.

 

Roger

 

 

Servo 0 No Servo 3

Edited by RogerH
Link to post
Share on other sites

It would be useful if those in favour of fitting a servo could state their reasons.

The only one I know of is simply the pressure required with unassisted braking which can be a problem for older drivers (as can the clutch, particularly the early non-diaphragm type) and also younger drivers that are not used to driving without one.

(Just trying to be constructive and not condemning those who want or need a servo).

Link to post
Share on other sites

I agonised over this and read through posts passim about the pros and cons of fitting a servo. On balance, and being a lazy s*d I went for a servo. One of the best features of my newly back on the road 4A is how good the brakes are especially compared to my previous TR6.

Link to post
Share on other sites

Peejay,

 

You have a point, but it may be biased: TR6 and TR4 have the same braking system but in the TR6 what you have to stop is an extra 50 bhp plus an extra 134 kg (1016 vs 1130). So you can't really compare.

 

Badfrog

Link to post
Share on other sites

Peejay,

 

You have a point, but it may be biased: TR6 and TR4 have the same braking system but in the TR6 what you have to stop is an extra 50 bhp plus an extra 134 kg (1016 vs 1130). So you can't really compare.

 

Badfrog

My 6 has a Non Working Servo :o No Problem Stopping or Locking Up and i aint on Green Stuff Pads either, Thank God :P .

 

4 to 1 Keep Counting.

Edited by TR NIALL
Link to post
Share on other sites

No Servo on mine anymore, brakes perfectly OK in my view.

 

If a remote servo sticks on then either the hydraulic piston that operates the air valve is sticking or the air valve itself isnt sealing properly. Remember, the servo works by having vacuum both sides of a 'big piston' when brakes arent applied .....and allowing air in to one side of that piston when the brakes are applied...if the brakes drag/don't release cleanly then there must be air when there should be vacuum.

Link to post
Share on other sites

I have the remote servo on my 4A and its most effective at town speeds where a light touch stops the car easily. When braking from higher speeds with a heavy foot the difference is not so great

So I am for it.

Link to post
Share on other sites

Thanks for all the feedback! Replying in some sort of order.....

I'm using new fluid, normal dot 4 stuff from Halfords.

It's Powertune, and I haven't asked them yet. I returned the first one to the TR spares supplier I bought it from; they swapped it and the replacement is just as bad, it's all out of warranty now so I will ring Powertune next. I was hoping all you experts out there might have come up with a simple answer:)

Thanks Dave in Malaysia for your view - this stacks up and points to a problem with the servo - again.

The brakes work(ed) ok before, which leads me to agree with the obvious trend here.... maybe a waste of money. I'm not sure what I was really expecting - something like Potts4A I guess. It seemed like a reasonable modern improvement. (I keep all the original bits but I'm not concerned about maintaining originality for my driving experience). I'd also like a headlamp flash on the steering column, and dip beam there too etc etc And a heater that works. Sacriledge :)

Frank

PS I can't really vote in your survey, Badfrog - never having experienced a servo that works....

Link to post
Share on other sites

the servo on my TR4, with the Mark 1 XJ6 calipers is nice, suits me, but I would like power steering as well don't condemn it until you've tried it.

 

borrow it for a try at Malvern no charge orders taken later on. With apologies to Mr Cornish, but I'm not as strong as him.

Link to post
Share on other sites

Frank,

 

Do you have a 'non return valve' in the vacuum line from the manifold? and is it fitted the correct way round?

 

Could be the cause of your problems.

 

I'm for the servo!! I acknowledge that TR brakes are good as standard and quite capable of locking up, the skill is stopping without locking the brakes.

 

I fitted a servo so that the difference between daily driver and TR was less noticeable.

 

Cheers

 

Graeme

Link to post
Share on other sites

Hmm ... Mr Cornish is aged (well past 70 - definitely well, and also past) and not very strong (10 stone weakling), but ran TR2s without servo in the 1960s, threw away the servo on 4VC as soon as he bought the car in 1969, and still runs the car without such assistance.

Like so many others, he loves the progressive feel that TR brakes give - push harder, stop faster!

 

As long as his right leg continues to work, he has no intention to fit such a piece of kit (even if he could find room for it).

 

Signed: Miss PA

pp Ian Cornish

Link to post
Share on other sites

I don't wish to appear rude but it's each to his own. Those that choose not to have a servo will not convince those that have a servo that their choice is somehow "not in keeping". And vice versa of course and that is the beauty of personal choice.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.