Struggling with rear brake balance MOT 1.9

[ScoobyJawa 23]

Put the car in for MoT and failed on rear brake imbalance. It’s had new callipers a few years back and they still are in good shape, garage said they appear fine.

 

he swapped the rear brake compensators from one side to the other and sure enough the low force moved with the compensator.

 

I ordered 2 new compensators (4861.49, the E model) and the garage has told me they just fitted them and now both sides have low force.  He said they only fit one way due to pipe sizes so defo on right way round. I find it hard to believe that both would be faulty….

 

he says the pedal has good force and feel, no sponginess so not air trapped anywhere.

 

We’re both at a loss now where to go now, defo need to install the new brake fluid rubber washer I got, but I can’t imagine that could cause the issue?

 

could it be the master cylinder?

 

Any advice would be most appreciated, poor thing is marooned at the garage with no MOT

 

it’s a 1990 1.9 phase 1.5, for info.

Edited June 27, 2022 by ScoobyJawa

[Tom Fenton 1,542]

The standard brake force on a 1.9 is quite low on purpose otherwise it will lock the rear wheels. The low force that moved with the limiter valve is the correct brake force. The high force at that time is the failed limiter valve. Politely tell your mot man that is how it is supposed to be.

[ScoobyJawa 23]

Thank you very much Tom, that makes perfect sense based on everything I've read about the rears, I've gone back to them so lets see what they say!

[welshpug 1,657]

I'd agree with tom, as long as it actually passes the minimum is fine.

 

 

worth making sure the pistons are properly adjusted, slacken and unhook the cables and give the pedal a good stomping, then re-adjust the cable.

[ScoobyJawa 23]

Thanks, I'm awaiting an update, they said they would try again to see if they can get enough efficiency.

 

If not I'll call it quits and book it in for an MOT at my usual place thats more used to old Citroen/Peugeots and let them sort it.

[ScoobyJawa 23]

Ok, he showed me the readout and the fronts were about 240-260ish IIRC, and the rears were high 40's/50.  I've seen some other figures on here that were roughly similar to that, so I guess thats about right?

 

Got it through with a bit of tweaking!  Will take it to my usual place next year for a full once over.

Edited June 30, 2022 by ScoobyJawa