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Old 05-15-2014, 11:59 AM   #1
White70C20
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Brake issues...

Hello all,

It has been a while since I was on here last. I've been busy with schoolwork.
Anyway,
Both of my pickups are having brake issues.

The green C20 seems to have a leak, even though I can't see any fluid leaking out on the ground. The only fluid I see collects on the underside of the master cylinder in little drips. The brake pedal also seems to require more movement than it should (it has power drum brakes). After driving 30-40 miles nonstop, the pedal can seem a little bit spongy. Also, the rear section of the reservoir on the master cylinder seems to loose fluid. I've never let it go dry, but whenever I check it (every couple weeks) it's always down half an inch or so, whereas the front section never seems to go down. Does anyone have any idea where the leak may be coming from?

The blue C20 (my grandfather's) has an entirely different problem. I am in the process of rebuilding the brakes on it. When I took off the drums I realized it still had asbestos shoes on it (hadn't had brake work done since the 80s!!!)
Anyway, the wheel cylinders are seized. I have attempted removing the bolts holding the wheel cylinders on several times (I have soaked them in penetrating oil, heated them up, etc.) and nothing seems to loosen them up. Does anyone have any ideas on how to remove those pesky bolts? I need to get the brakes put on over the next three days so I can lower the truck back down on its wheels so I can put the engine back in.

Thanks!
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Old 05-15-2014, 12:46 PM   #2
Mr Chevorlet
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Re: Brake issues...

What i have done in the past,when the heat will not work is to tighten the bolts until they twist of and replace all with new wheel cylinder and bolts. it the quickest also. air Impact also does wonders. with getting bolts out.
And your other issue could be leaking fluid to the inside of your cab. Pull your mat or carpet back and you will see it. If so, time for a master cylinder change.
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Old 05-15-2014, 01:08 PM   #3
cdowns
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Re: Brake issues...

+++ 2on breakin the bolts it's the easy way to do it

i think your leak needs a new master cylinder
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Old 05-15-2014, 05:28 PM   #4
White70C20
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Re: Brake issues...

Thanks guys!

I just had the master cylinder replaced a year ago. Could it be a bad unit? I see a drip on the underside of the master cylinder that never seems to go away. The booster is dry as a bone. The master cyl. bolted tight to the booster as well. I just can't see how it could be leaking down into the cab, and how is that drip on the underside of the master cyl. getting there?


In regard to the stuck bolts, I agree that twisting them off would be the best bet, but I can't get a socket in there. The wrench I was using on the one side is too big for the other side's bolts. I'm not sure if I'll be able to twist off the bolts using a wrench or not.
Also, one of the wheel cylinder bolts is rounded off. How do you recommend I remove that bolt? I'll be heading out to work on the truck this evening, so I hope I can get them removed tonight.
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Old 05-15-2014, 05:34 PM   #5
Mr Chevorlet
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Re: Brake issues...

Your correct, my bad didn't see you had power brakes and you will not see any brake fluid in the cab but only in the booster. But one way or another your master cylinder is leaking
It needs to be replaced.
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Old 05-15-2014, 06:14 PM   #6
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Re: Brake issues...

Either leaking out back which would run down front of booster or your rear fitting is leaking which allows fluid to drip down to bottom of master.
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