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Contaminated brake shoes - can they be cleaned?

AR67GTX

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Made a dumb error and didn’t get the wheel cylinders rod connected to the shoe somehow. The piston over extended and leaked some DOT5 on the shoes. Of course the internet has 50% saying it can be cleaned with brake cleaner and 50% saying it can’t.

So those that do a lot of brake work, what do you say? Does DOT5 make any difference?
 
I did an apprenticeship as a car mechanic 50 years ago.
If only a tiny area you may be ok but the worst thing is the side that didn't get doused will most likely be a stronger brake. The brake imbalance could show up in the wet weather.
They should be replaced - no real way to get the fluid out.
 
How much is your peace of mind worth? Did the same thing 46 years ago on front driver's side. Was slowing down for a red light thank god I was early on the brakes. That little extra time to ge in the gutter and not hit him, stopped at the passengers door. I had driven 10/15 miles before it popped so it was a shock.
 
Yeah, that silicon seems to be the unknown element. Bummer, had good stopping power too. Guess I’ll get in contact with Craig at Mobileparts.
 
They should be replaced - no real way to get the fluid out.
Totally agree.....once those shoes are soaked, it's time to replace them.

Why risk your pride & joy with dodgy brakes?
 
In most cases ,
Your LIFE is a lot more valuable than a set of Brake Shoes.......

Sometimes , better to say , " Aah , bleep it , sh!t happens "

I will take care of you on a second set , such that it is more palatable....
At least it will be less painful.....

Once contaminated with Brake Fluid of any DOT , best to label them " done " .....

Yours , Craig.....
 
Well I go against the grain ... brake shoes are usually very dense and spilled fluid doesn't get very deep. I wipe them down with a very generous amount of lacquer thinner. I do it a couple or more times - wipe with a wet paper towel then with a dlean dry one to soak up the stuff - never using the same towels twice. When there is no more "wet spot" I give them a good dousing with brake cleaner.
 
Well I go against the grain ... brake shoes are usually very dense and spilled fluid doesn't get very deep. I wipe them down with a very generous amount of lacquer thinner. I do it a couple or more times - wipe with a wet paper towel then with a dlean dry one to soak up the stuff - never using the same towels twice. When there is no more "wet spot" I give them a good dousing with brake cleaner.
I'm mostly with you but silicon is not a liquid, in pure form it melts at around 1400C, the problem as I see it, it's never going fully away until the lining wears out away. The liquid that transports it as brake as a fluid silicone compound will likely at some point be removed by abrasion and/or evaporation, but not any decomposed silicone.
 
Laquer thinner and a litle 100 grit sandpaper. Fluid doesn't soak very deep into the shoe material.
Doug
 
We used to clean them with carbon tetracloride but that was taken off the market in the 70's as a nasty cancer causing agent.
 
Used to race FV in the SCCA and had a rear seal fail allowing ATF from the trans to completely saturate the left rear brake shoes. Replaced the seal, cleaned off the ATF from the brake hardware and hand sanded the shoes. Reassembled and the rear brakes worked find. No problem stopping from 100+ mph on the track. Just hand sanding the saturated left brake shoes worked for us at the track that day.
 
Well gang - riddle me this.

I have new shoes for the front ordered but in the meantime I needed to move the car. So I cleaned the drums and shot the shoes with Brakekleen, sanded with 120 and wiped them down 3 or 4 times with 99% isopropyl alcohol and temporarily reinstalled them. They looked pretty good.

Here is the mystery. It was the left front shoes that got DOT5 on them - and probably only the inside inch roughly. What caused me to start investigating was the car suddenly started diving off to the left when I hit the brakes. You can feel it steering the car so I figured something up front. But, why would it pull in the direction of the contaminated side??? So, after cleaning and readjusting, verifying the primary shoe was up front on all corners (it wasn’t - the contaminated set was reversed - not sure what iteration that occurred in - maybe after cleaning and absent mindness), primary spring hooked first, and adjusting for no drag - I couldn’t resist a test drive down the street and it still dives off to the left. Back off the adjustment some more on the left side and it still dives left.

The last test after more adjustment I noticed the steering was getting slow in the center (all power steering just added). After a few minutes I remembered I’ve been here before when I replaced the power steering box in my 67 - the dang box to frame bolts that I tighten the heck out of had gotten loose. Thinking maybe this is part of the problem, I pulled the bolts, doped up with blue Loctite and tightened the heck out of them again. Just went down the street again and steering is good again but the car still steers left when applying brakes!!! Crap.

The only thing I originally did with the brakes was replace all wheel cylinders, both front rubber hoses, flush the hard lines, replace the MC and add DOT5. Why would the car steer in the direction of the contaminated side?

Could it be the rear brakes? This car has a later Dana in it with self adjusting brakes. Just before this all started I did a couple rearward stops to make sure the brakes were adjusted up OK in back. I went back after this and adjusted them as best as I could - even checked them with a temp gun to get them as even as I could by backing a few clicks off on the warmer side. It’s difficult with sure grip and all the differential drag.

With my wife operating the brakes, the MC seems to be releasing pressure fine. But I’m wondering if I should just replace the hoses and wheel cylinders again. Alignment is good, tire pressure is even. The brakes have been fully bled twice and pedal is hard. I’m hoping the new linings miraculously solve the mystery. But I’m not much for miracles.

Anybody got any ideas? Probably be next week before I get the new linings and install them.
 
It is not likely to be the rear brakes if it is "winding" the steering wheel to the left.
The rears can have a huge imbalance before they cause the steering wheel to pull around.
You could try bringing the right hand side up a bit tighter to try and balance the application point.
If after both brakes apply the steering does not "balance" up and stop pulling so hard I would say you have another issue.
Your description was good but you have to go on gut feel a bit.
Front drums can be painful to get right.
 
Well you seem to be a sucker for punishment so why not swap the shoes sise to side and see what happens.

Another thought is a pinched right line or similar restriction.
 
Well you seem to be a sucker for punishment so why not swap the shoes sise to side and see what happens.

Another thought is a pinched right line or similar restriction.

Well, now that’s an original thought. With the wheel covers off I can swap brakes pretty quick, although I need to double check my work more carefully. I just may try that out of curiosity.

Thanks.
 
Well gang - riddle me this.

I have new shoes for the front ordered but in the meantime I needed to move the car. So I cleaned the drums and shot the shoes with Brakekleen, sanded with 120 and wiped them down 3 or 4 times with 99% isopropyl alcohol and temporarily reinstalled them. They looked pretty good.

Here is the mystery. It was the left front shoes that got DOT5 on them - and probably only the inside inch roughly. What caused me to start investigating was the car suddenly started diving off to the left when I hit the brakes. You can feel it steering the car so I figured something up front. But, why would it pull in the direction of the contaminated side??? So, after cleaning and readjusting, verifying the primary shoe was up front on all corners (it wasn’t - the contaminated set was reversed - not sure what iteration that occurred in - maybe after cleaning and absent mindness), primary spring hooked first, and adjusting for no drag - I couldn’t resist a test drive down the street and it still dives off to the left. Back off the adjustment some more on the left side and it still dives left.

The last test after more adjustment I noticed the steering was getting slow in the center (all power steering just added). After a few minutes I remembered I’ve been here before when I replaced the power steering box in my 67 - the dang box to frame bolts that I tighten the heck out of had gotten loose. Thinking maybe this is part of the problem, I pulled the bolts, doped up with blue Loctite and tightened the heck out of them again. Just went down the street again and steering is good again but the car still steers left when applying brakes!!! Crap.

The only thing I originally did with the brakes was replace all wheel cylinders, both front rubber hoses, flush the hard lines, replace the MC and add DOT5. Why would the car steer in the direction of the contaminated side?

Could it be the rear brakes? This car has a later Dana in it with self adjusting brakes. Just before this all started I did a couple rearward stops to make sure the brakes were adjusted up OK in back. I went back after this and adjusted them as best as I could - even checked them with a temp gun to get them as even as I could by backing a few clicks off on the warmer side. It’s difficult with sure grip and all the differential drag.

With my wife operating the brakes, the MC seems to be releasing pressure fine. But I’m wondering if I should just replace the hoses and wheel cylinders again. Alignment is good, tire pressure is even. The brakes have been fully bled twice and pedal is hard. I’m hoping the new linings miraculously solve the mystery. But I’m not much for miracles.

Anybody got any ideas? Probably be next week before I get the new linings and install them.
There must be a reason, where as I don't believe in magic. Whether I am smart enough to figure it out is anybody's guess,

My guess the BF and cleaning solvents softened/changed the grip of the lining. Now whether that is permanent or not is another guess, A number of hard stops with adequate cool down cycles would be next test/discovery or not.:lol:
 
I’ll swap the linings and drums in the morning. If the swerve moves to the right then somehow those contaminated shoes just mysteriously became grippier. But the new shoes should resolve that. If it stays to the left then I will probably change out the wheel cylinder and hose again on the right and double check the hard line. Something did get kicked up under my car and dented the oil pan. Always possible it somehow got the brake line too.
 
Why not in the morning just go do 3? 50 to zero hard stops, park it. wait a half hour, have breakfast, repeat again, wait another half hour, and then test drive, and all with only washing hands once for breakfast? Or tear it all apart and see if you have moved the problem?:luvplace:
 
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