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Old 05-06-2010, 08:18 AM   #26
bcj67chevy
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Re: Brake expert help needed!!!!

I will have to give prop valve thing a try this weekend?

Thanks guys!!
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Old 05-06-2010, 09:32 AM   #27
jpert
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Re: Brake expert help needed!!!!

IF you crack loose the line at the MC and no fluid comes out it is obvious the ports or fittings on the Mc are not open. This should be easy to check. If it was me I would remove the line at the Mc and gently blow air through the port or disassemble and inspect the ports in the casting. If it is new just take it back and have it replaced.
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Old 05-06-2010, 10:01 AM   #28
smn69
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Re: Brake expert help needed!!!!

Quote:
Originally Posted by bcj67chevy View Post
I must not be understanding something, if I try to bleed the rear brakes at the fitting that connects directly to the mc, before the fluid can go thru the prop valve, then how can the prop valve affect the fluid that is is coming directly out of the mc?

I'm not trying to be difficult i just don't understand!!

Thanks guys for being patient!
If you can't get any fluid out of the MC directly, you need to check the piston travel in the MC. If it is not coming all the way back to the snap ring where the rod goes in, it is not opening up the channel for the fluid to move through.
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Old 05-06-2010, 11:22 AM   #29
bcj67chevy
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Re: Brake expert help needed!!!!

Thanks guys, will give it a try.
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Old 05-18-2010, 08:41 AM   #30
bcj67chevy
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Re: Brake expert help needed!!!!

Changed the front caliper that had the broken bleeder, bleed the front brakes with no problem.

Then I bleed the rear, this time some fluid came out and i was able to get the air out, but the fluid didn't come with much force just a slow stream. Also when the brakes were pumped up the pedal was rock hard and only went down a inch or so, then when the rear bleeder was broke free the brake pedal didn't go to the floor. Shouldn't the pedal always go to the floor when bleeding??? When i bleed the front the pedal went to the floor like normal.

Should the pedal be rock hard like that from the beginning and not really be able to pump up the brakes??

If the rear brake hose was partially collapsed could this cause the issue??

Hopefully next week a will be able to take it for a test drive and see how it goes.

If the prop valve still needed recentered or was bad then i wouldn't get any fluid out of the rear at all right?

Anyone have anymore ideas to try??

Thanks guys!!
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Old 05-18-2010, 05:38 PM   #31
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Re: Brake expert help needed!!!!

You might want to check to see that you have some freeplay in the pushrod going into the M/C. If it is too tight, the piston will not return enough to open the return port . . . meaning no fluid to bleed at the wheel or M/C!
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Old 05-18-2010, 05:55 PM   #32
bcj67chevy
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Re: Brake expert help needed!!!!

I'm getting fluid now to the rear brakes just not much pressure, not sure how much there should be even.

My biggest thing was that the pedal wasn't going to the floor.

As far as the push rod, the brake pedal seems to go down very freely with almost no force for the first inch then rock hard. not sure if there is that much play before the rod actually reaches the piston or not. Thought about taking mc back off to see if the rod needs adjusted out or in.
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