one for the mechanics

[tony46]

Right here we go, Maverick failed MOT, they said the servo was not working correctly(spongy brake pedal) they rang today to say the have tried replacing the servo to see if it that was at fault(strange when they said it was when they failed the MOT).They have checked all the brake pipes, replaced all the brake fluid, with no change.I have given them untill tomorrow to find the fault or I will bring it home and look into the fault myself, with some help from my friends on here,so has anybody got any ideas?
:doh

 

[Adz]

Could well be the calipers seized up & not working correctly

Cant see why the servo would fail & surely you would have brakes or no brakes :nenau

 

[The Patrolman]

Could be a 'Blebbing' brake pipe!!! If that makes sense??
If it was a sticky calipper the brake test should have shown low braking effort on one wheel??

 

[tony46]

Hi, well yes I agree, on the way to the MOT I tried the brakes and they stoped me on a sixpence,so I am more confused than ever.The mystery continues.:doh

 

[Adz]

Could be a 'Blebbing' brake pipe!!! If that makes sense??
If it was a sticky calipper the brake test should have shown low braking effort on one wheel??

Not always as mine was 1/2 siezed & scrapped it but naturally sorted it :thumbs

 

[Adz]

Hi, well yes I agree, on the way to the MOT I tried the brakes and they stoped me on a sixpence,so I am more confused than ever.The mystery continues.:doh

Goto a different MOT centre & ask if they will do a brake test for you :thumbs

 

[clivvy]

yeah,...this sounds odd. they should have put the car on the brake testing machine, so you either have brakes, or no brakes (or poor handbrake efficiency), so how at the MOT stage do they know its the servo>? seems to me a bit fishy. anyway, check the cylinder, check the flud and check the calipers, could be air in the system?

 

[11redrex]

Had a spongy pedal on my last car and it was something to do with the abs pump. it passed the brake test on the mot like it though. I thought if it passed the test on the brake meter that was that ?
just my 2p's worth.

 

[makeitfit]

Well before the beer kicks in too m uch!:sly
How long have you had the truck and have you ever changed the calipers?
Bizzarly the callipers are handed \BUT although they do fit both sides the bleed nipple can be at the bottom of the caliper not the top.:augie
Are you there yet?
Any road up , if that's the case brakes will work but any air in there say 'cause your garage refilled the fluid, then it cant be bled properly.
Worth a quick spy
The other thing could be the brake compensator thingy on the back of the truck.
Usual fix is lots of wd40 a big hammer and some er persuasion :naughty

 

[tony46]

Had the Maverick approx 18 months, never changed the callipers,however, have ordered some today from a member on here(thought best to have a few spares).

 

[makeitfit]

Compensator then, that has a nipple at the top and gets proper cruddy and forgoten about.
Ask the garage to check they've bled there too

 

[tony46]

when you say at the rear of the truck, where abouts? and is it easy to see.

Thanks

 

[makeitfit]

Walk under the back and look up over the back axle :thumb2
It's mounted up there in all the crud
Enjoy

 

[tony46]

Thanks will take a look tomorrow :thumbs

 

[makeitfit]

Just follow the brake pipes into the mud :lol

 

[Adz]

Its the small box over the axle isnt it

 

[rustic]

Its the small box over the axle isnt it

With a lever, and a large extension spring attached.

 

[tony46]

Well back to the drawing board, we have tried all of the above with no joy!!
Well I am thinking of renewing the whole of the brake pipes.

 

[Toolbox]

Have you checked the rear brakes are well adjusted?

 

[macabethiel]

MoT brake failure

Right here we go, Maverick failed MOT, they said the servo was not working correctly(spongy brake pedal) they rang today to say the have tried replacing the servo to see if it that was at fault(strange when they said it was when they failed the MOT).They have checked all the brake pipes, replaced all the brake fluid, with no change.I have given them untill tomorrow to find the fault or I will bring it home and look into the fault myself, with some help from my friends on here,so has anybody got any ideas?
:doh

If it has failed the MoT did they give you the readings on the brake test ? The rolling road MoT test will give you a percentage of braking for each wheel on each axle and an overall percentage plus the handbrake percentage. Finally the only actual brake servo test I am aware of is when they apply the brake pedal with the engine not running and whilst holding the brake pedal down you start the engine. If the servo is operating the pedal will go down slighly as the brake vacuum is activated.

Out of interest if you repeatedly pump the brake pedal with the handbrake off and the engine running does the handbrake light come on at all ? This is a shared function light on some models and would indicate a servo / brake booster fault. I had this on my motor and it was a perished vacuum hose on the T piece just off the servo. Fixed for about £5.00 worth of silicone tubing.