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Discussion Starter #1
Good golly Miss Molly! Yesterday I needed make an evasive move to avoid a traffic jam. I did a hard 60 degree left turn going faster that I would like. As soon as I completed the turn, white smoke started billowing out of my tailpipe. James Bond would have been proud of the smoke screen I laid down. The smoke only lasted about 10 seconds then went away. Car drove fine during the smoke screen and after. Today at lunch I did a U-turn at a bit of speed and lo and behold, the smoke screen came back.

What can be causing that? I put a new head gasket on last summer. Car never smoked like this before, and I am sure I have made spirited turns in the past. I will get an occasion puff of blue smoke, but I know I need a valve job(this winter). Never anything like this.

1750 engine
 

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Discussion Starter #3
Dolmon, I thing you may on to something. I posted previously that I have noticed my low brake fluid light has gone on twice in the last two weeks and I needed to fill the reservoir. I was told to check the booster. Being a dunce, I'm not sure what that means. My car has a single booster. What am I checking?
 

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Take off the hose on the booster and stick something down in there and if the end is wet you need a new booster .It has a leak.
 

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If there is fluid in the booster (which seems a likely cause) then your brake master cylinder is leaking, not the booster. The fix is a new MC.
 

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Discussion Starter #6
I was told to undo the bolts hold the MC to the booster and if the back of it is wet, then the MC is bad. I will do the "dipstick" trick too. thanks
 

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leaky booster/mc or not... i reckon the reason brake fluid is coming out of the tail pipe as white smoke is the check valve from the intake port to booster has failed allowing fluid into the motor.

the check valve is the silvery thing that on the intake manifold runner closes firewall with hose attached to it. disconnected it, plug the hole and drive it to test it to see if it still smokes. be extra CAREFUL since your pedal effort has doubled or tripled without the vacuum assist.
 

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But Mad North-Northwest
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leaky booster/mc or not... i reckon the reason brake fluid is coming out of the tail pipe as white smoke is the check valve from the intake port to booster has failed allowing fluid into the motor.

the check valve is the silvery thing that on the intake manifold runner closes firewall with hose attached to it. disconnected it, plug the hole and drive it to test it to see if it still smokes. be extra CAREFUL since your pedal effort has doubled or tripled without the vacuum assist.
That's not how the check valve works. The check valve allows flow from the booster to the engine. If there's fluid leaking into the booster it'll get into the engine even with a perfectly functional check valve.

The check valve is there so if the engine shuts off or you've got low engine vacuum you still have vacuum stored in the booster to enable power brakes.
 

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That's not how the check valve works. The check valve allows flow from the booster to the engine. If there's fluid leaking into the booster it'll get into the engine even with a perfectly functional check valve.

The check valve is there so if the engine shuts off or you've got low engine vacuum you still have vacuum stored in the booster to enable power brakes.
you maybe correct come to think of it... i forgotten, its been many years since i removed my boosters and welded that check valve shut! thanks
 

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I had brake fluid in the booster many years ago. I mopped it up with paper towels and it has been fine since then. No removal, disassembly, etc.
 

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But Mad North-Northwest
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Yeah, if you take off the MC and just kinda swab the booster out with some soap and water it'll probably be okay. The fluid isn't great for the rubber diaphragm but it's not like it's an instant death sorta thing.
 

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Discussion Starter #13
Hi all. Weekend plans to dig into the MC and Booster. Weird thing is, almost all you mention is brake pedal feel. I feel no change in the effort to push the pedal. Car stops as it always has. Hopefully it's just a bad MC and not the whole booster.
 

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Weird thing is, almost all you mention is brake pedal feel. I feel no change in the effort to push the pedal. Car stops as it always has. Hopefully it's just a bad MC and not the whole booster.
No, that makes sense. The booster hasn't been harmed (yet) by the presence of brake fluid. And the MC is working OK - it's just leaking fluid from its rear seal.

You could run this way forever as long as you added brake fluid periodically - sort of like dealing with an engine that burns/leaks oil but otherwise has good oil pressure and compression.

The issue is that eventually the brake fluid will damage the booster diaphragm. At that point, your brake pedal will become harder. And of course, you look silly with all that white smoke on every hard turn!
 

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Discussion Starter #15
Thanks Jay. I didn't want to mention that I am still driving the car, knowing from what has been posted that the diaphragm is slowly being eaten away. Kids being home from college, leaves me no other car to drive.

The braking system on my car was completely replaced by the previous owner around 15 years ago. So I am guessing that the in the lifespan of an MC, that mine is relatively young. Or maybe not. Is an MC repairable? Or it's just not worth the hassles and just go for a new one for $75 from Centerline.
 

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Don't count on current aftermarket cylinders lasting that long.
 

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Remembering all the time that brake fluid eats paint.... so whatever you do booster / MC & brake fluid-wise, mop up, clean up, rinse well & dry with clean paper towels.....

Been there, done that, rebuilt the boosters several times

Ciao
Greig
 

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Lots of water is all that is required to save paint from brake fluid. What you do after the water is a personal choice and irrelevant ... 🙂
Pete
 

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Is an MC repairable? Or it's just not worth the hassles and just go for a new one for $75 from Centerline.
Yea, you answered you own question. Sure, you can rebuild a MC. But the kit costs a few bucks and rebuilds aren't always successful. So if you can get a new one for $75, it's probably the better deal. Especially when you factor in your time to R&R the MC and bleed the brakes.

alfaparticle said:
Don't count on current aftermarket cylinders lasting that long.
Right! So if you got 15 years out of the last one, you're doing well.
 

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Worn valve guides could let a lot of oil flow into the cylinders when g’s from a hard turn piles the oil up to one side of the cam tray. My 88 Spider sucks it down the exhaust valves on hard right hand turn. Believe the exhaust side has no valve stem seals.
 
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