MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - bleeding brakes again ...

good evening all
1500 midge single circuit brake system. New rear wheel cyl Bled with easy bleed and had a hard pedal but a lot of travel..Pedal almost to floor. Back shoes are wound up tight and hand brake on. There is no spongyness to indicate air in system. Previous to fitting the new rear brakes the pedal was not a lot higher but always just passed mot I have just been out for a ride hoping the pedal may come up, but no. During the bleeding exercise i tried the pedal with the easybleed still powered up and connected..The pedal was hard with virtually no travel.It is almost as if the pushrod is too short. BTW i also have a servo and this is angled up as advised to prevent airlock in servo
Should i ditch the servo or fit new mcyl if so what make
rgsd tony
tony boyle

ditch the servo leaving all else the same, and report back.
David Smith

hi david
thanks your reply..i was thinking that..i will bipass the servo and see what is what
Job for later in the week !

rgds tony
tony boyle

Servo is a bit unnecessary on a midget IMHO. Even on the MGB it was optional.

I had considered fitting one to my B, but decided it wasn't worth it.
Dave O'Neill 2

I struggled with getting a good pedal feel last year. In retrospect I think a sticky handbrake linkage was part of the problem, it wasn't allowing the rear shoes to move enough to self adjust.

Service brakes were good enough for MOT, even with long pedal but it failed on handbrake. Once I stripped, cleaned and lubricated that it passed and the pedal improved too.
AdrianR

hi all
just reinstated original brake system and hey ho a
hard pedal with no free travel !!!
Anyone want to buy a servo ??? !!!!!

tony
tony boyle

Assuming it is fitted correctly, my understanding is that it's impossible for any servo to create excessive pedal travel (in any car).

The servo diaphragm sits in contact with, and between, the pedal-end and BMC push rod. How can it create excessive pedal travel? Can somebody please enlighten me? Thanks.
J Thomson

That is because you are talking about a Direct action servo, and Tony is talking about an indirect action servo, have a read up and you will see that they work differently.
Andy Tilney

Re. direct action servo vs indirect action servo. Thanks, Andy. I see the difference. I must say, the indirect action variety would present a serious problem if it had a major failure. Potentially one could lose all footbrake. Unlike the direct action servo, where worst case failure would 'merely' result in a very heavy pedal.
J Thomson

Yes you are right, a fault on a indirect servo can cause a complete loss of your brake pedal, with all your brake fluid going out the exhaust pipe, but most times you will get a bit of a clue before this happens
Andy Tilney

hi
when i bought the servo the seller warned me to make sure the servo was 'pointing uphill', which is a bit fiddly on the midget. the
reason was,he said, that they can be difficult to bleed if they are fitted horizontally..Anyway problem solved, no servo and excellent brakes
thanks all your interest

tony
tony boyle

You don't always get a warning before an indirect servo fails. On the V8 Register board a handful of MGB GTV8 owners have suffered total and sudden loss of the brakes. Not good for the underwear. A Midget surely doesn't need a servo and I can't imagine why anyone would fit one. Even the MGB's brakes are perfectly fine without a servo - not heavy and a much better pedal feel without.
Mike Howlett

If you regularly or perhaps irregularly switch between driving a modern car with heavily servo assisted brakes and a Sprite/Midget with no servo after the first few unpleasant surprises you might decide it's worth the bother to fit a servo.

I suppose if you have a lovely wife/girlfriend with amazing slim sexy but not very muscular legs drive your Sprite/Midget that might also be a reason for fitting a servo to the car.

On the other hand if you only ever drive old cars without brake servos you will most likely live happily ever after until you have a hire car (you'll be glad you wore a seat belt).

If you can't bleed the brakes with a remove servo mounted horizontally either the servo is faulty or you have pipe runs with loops that are trapping air that you need to remove with conventional or assisted bleeding.

My Sprite does have a remote servo but it's the large disc and brake caliper conversion that gives it excellent stopping power, helped by the lighter than average weight of car and driver. The only thing I have against the servo is the weight penalty that comes with it.


Daniel

My exquisitely beautiful girlfriend with sexy legs had no trouble driving Arthur and he has no servo fitted.
Midgets are rather light anyway so not a lot of force required to stop them.
My philosophy is if it ain't broke, don't fix it and the guys who designed my car know, or with the passing of time, knew more than me.

Clive from Canada
Clive from Canada

All Midgets are not equal in how much pressure is required at the brake pedal or how much they weigh and that's why the 1500 Midget has a brake pedal with a different ratio to the pedals found on the earlier cars.
Daniel

This thread was discussed between 10/06/2018 and 18/06/2018

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.