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Old 08-05-2011, 03:13 AM   #1
mud slut 350
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Squishy brakes suddely!!

So heres the story... on my 82 k10 i was installing the pedal setup for my conversion from a th350 to a sm465 which was a pain in the . I removed the column and in order to pull the pedal setup i had to pull the brake booster and master off the firewall so i could pull the pushrod out far enough to pull the pedals out. I DID NOT disconnect any brakelines or empty the master at all. all i did was pull the nuts off and back the booster and master off the firewall. put everything all back together with the new pedals and all. i went to drive the truck and the pedal went right to the floor . before i did this i could barely push the pedal all the way to the floor and even running 35x12.5s would lock up the front tires on bone dry asphalt. Now it will go to the floor easily. it still stops the truck but probably longer stopping distance than a semi hauling a full load of sod. also when i press the pedal it hisses in the hole the push-rod goes into the booster (obviously vacuum leak). fluid is full and there are no leaks anywhere. ive bled the brakes at least 4 different times and get solid stream with no bubbles. I know the booster is shot now obviously but thats no reason for a soft pedal it should be really hard still and i should still be able to stop. Any help would be great if i can get out of just buying a booster and use the master i have. any help would be great!
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Old 08-05-2011, 06:41 AM   #2
D13
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Re: Squishy brakes suddely!!

Did you use the correct length push rod? Hook the pushrod to the correct hole? If the pedal connection is positioned rearward or at a different angle the pushrod may not be working the MC until the very end of the stroke.
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Old 08-05-2011, 04:41 PM   #3
88Jimmy4x4
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Re: Squishy brakes suddely!!

Did you hook up the vaccum line to the booster?

check that plastic connection for leaks
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Old 08-05-2011, 05:29 PM   #4
mud slut 350
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Re: Squishy brakes suddely!!

Yes I did im not as concerned with the boster as I am the master if the booster sh**s out the master should still work on its own but with a hard pedal. My pedal goes right to the floor almost no braking power lines have been bled several times maybe blown seals inside master? Idk
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Old 08-05-2011, 08:35 PM   #5
burb1085
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Re: Squishy brakes suddely!!

I've seen a post some where that your front brake lines get worn out and cause that condition, but it still doesn't explain why it would decide to crap out after you disconnected the booster and master. Just saying it's worth taking a look.
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Old 08-05-2011, 10:22 PM   #6
motornut
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Re: Squishy brakes suddely!!

find any fluid between the master and the booster
or running down from the master/booster joint area
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Old 08-05-2011, 11:04 PM   #7
mud slut 350
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Re: Squishy brakes suddely!!

nothing runing out between them levels are still the same i never seperated the two just backed them off the firewall my buddy held them i pulled my pedals out put the new in and put the combo back on the firewall...
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