Master cylinder help please

[7D2N]

My master cylinder has been leaking between the booster and the cylinder, the brakes worked fine or seemed to. Can I put a new gasket in or is this a sign of a bigger problem.

Thanks for any info
7D2N

 

[AJs72K5]

There's no fluid stored in the booster and as such no gasket between them. Using vacuum from the engine, the booster merely amplifies the pressure you apply with the pedal to the master cylinder piston. The leak you are seeing is likely coming from the cap of the master cylinder.

 

[sponsoredbydad]

For a split second I thought you had one of my old pictures.HA HA HA. Yea no fluid in booster itself , but it can leak from the back where the pin pushes in and there is a rubber seal there. BUT more likely than not he is right the cap is letting fluid weep and thus dripping down to eat all the paint. Change the master it's cheap insurance.

 

[4X4HIGH]

Brake fluid leaking from the rear of the master cylinder will eat the diaphram in the brake vacuum booster. I'll just about guarantee that the fluid IS NOT coming from the lid but rather from the rear of the master cylinder.

 

[Greg72]

Since I just fought with a braking issue like this not too long ago, I'll give you a bit of advice....

Once you replace the master cylinder you might be better off to also replace the booster at the same time (especially if you see any fluid in it when you pull the master off). The brake fluid will ruin the seal inside and it will be IMPOSSIBLE to bleed the system and get correct pedal pressure and braking power.

I didn't realize that and went through the entire swap of the master cylinder....then struggled for a couple hours trying to bleed and rebleed my brake lines. Once I finally realized that the booster was at fault and swapped it out the brakes bled instantly and performed awesome again.