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Triumph Repair/brakes/carb


applying brakes i hear a sound like an air leak then white smoke in abundance comes out of the exhaust. I have a 1973 TR6

Hi Douglas,

That sounds like a leaking master cylinder into a vacuum brake booster. The white smoke is most likely brake fluid and you should note loss of brake fluid too.

When master cylinder seals go bad, the fluid can leak into the vacuum booster and then the manifold vacuum draws the fluid into the combustion chambers and burns it, thus the white smoke. The two sources of white smoke out the exhaust are coolant and brake fluid. Yours is most likely brake fluid. The noise you hear when stepping on the brakes is air and brake fluid entering the vacuum of the intake manifold.

You should fix the brake master cylinder and that has probably damaged the brake booster too.

Let me know,


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Howard M. Fitzcharles III


Triumph TR-4 up & Spitfire, and Engine theory


Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.

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ASE Master Auto with L-1 certification up to 2000

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