Brake upgrade and now no brakes!!

[Lucian_rider]

Hi all,

My son and I have just completed an engine swap in a 180 SX that originally had an RB20 swap but as it was in poor shape and the swap was lousy to begin with we have done an SR20 swap.

The original owner had put a set of Skyline four piston caliper front brakes and supposedly the master cylinder and booster. I have my doubts as the MC piston is only 7/8" and I believe they should be at least 1".

We had a complete front cut of an S13 so we took the MC and booster as they are in much better condition, the piston size is 15/16" which is marked on the side of the MC. The previous system worked strongly but there was an excessive amount of pedal movement before the 10 pistons would all take up. I was hoping that the new MC would have alleviated most of the play.

Anyway after bleeding the system with the engine off, (there was no engine installed at the time), a quick test run today reveals almost no brake pedal travel and very poor stopping performance.

The vacuum line from the manifold sucks but kind of slowly. I have yet to check the non return valve or an airtight check as per the manual.

Could this be a proportioning valve problem?

I want to get this sorted tomorrow so I would love some suggestions as to what I should do first. There does not seem to be any air in the system as the pedal hardly moves.

Thanks in advance for any help.

Chris

[Lucian_rider]

Well I found the problem.

Mud wasps had again built a nest in the vacuum line for the brake booster whilst the engine was out of the car....

Removed line, dug out nest, reinstalled and now the brakes work perfectly.

If I could now figure out why the engine is running hot!