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Discussion Starter #1
I now have my carb on my 65 coupe and the engine sounds good, but I was pumping my power brakes last night because they felt spongy and I noticed a lot of blue smoke billowing out of the exhaust. Is this brake fluid being forced into intake manifold and is this normal? I notice that I am using a lot of brake fluid and I am not sure where it is going. I haven't noticed any obvious leaks, but I still need to check my brakes before I take it out on the road. Any help would be appreciated.
 

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Its awfully hard for brake fluid to get into the intake ;)

Is the smoke coming from inside of the pipe or just from everywhere...it could be brake fluid leaking onto a header and burning off....do you have power or manual brakes?
 

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You already know where the brake fluid is going.
You have a bad master cylinder. it is leaking into the booster and is being sucked out of the booster by the engine vacuum and being burnt
 

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You have all the indicators; blue smoke, spongy pedal, loss of fluid. Sounds like bad seals in the master cylinder to me that is allowing fluid back into the boost mechanism. If it was mine I would be getting in some other car and going to the parts store for a master cylinder. But... I have been known to buy the wrong part before. Maybe you get more opinions.
 

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Discussion Starter #5
Sounds like you are right on regarding the Master cylinder and power booster. The smoke is definitely coming out of the exhaust pipe and not just being burnt off the exhaust from a leak. How difficult is it to replace the master cylinder on the power brakes of a 65?
 

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its a pretty easy job.

Just need some line wrenches, a set of 3/8 drive rachets, a bottle of brake fluid and a few minutes....just remember to bend bleed the new MC first and if you are careful, you won't even need to bleed the lines.

whoops....bend bleed - BENCH Bleed....I'm all thumbs today
 

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Discussion Starter #7
Thanks for the advice. I am unfamiliar with the term "bend bleed" on the master cylinder. What exactly should I do to bend bleen the MC when I am putting it on?
 

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bend bleed"
= Bench Bleed. Personally I prefer to bleed it in the car using a piece of brake tubing (or 2 if you have dual MC) from the outlets of the MC back below the fluid level in the reservoirs. Pump it till no more air bubbles up from the tubing and then reinstall your brake lines and bleed the wheel cylinders.

Much less mess that way, IMO.

EDIT: Perhaps that's what Nick meant by bend bleed as you need to bend the tubing back into the MC reservoirs?
 

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I think he means "bench bleed" the master cylinder. There will be instructions in the kit, but usually, there are two plugs with the MC. You screw them into the brake line ports, fill the master cylinder with brake fluid, and then with a dowl rod or something similar, you pump the master cylinder (like you would when pumping the brakes) until there are no bubbles in the fluid. Make sense?
 
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