Brake problem.

Let me start by saying discs in the front, drums in the rear.
I haven't driven my truck in over a week. Today I got in, cranked it over and stepped on the brake before I shifted. The pedal traveled about an inch and felt rock hard. Booster is working. I opened the line at the front "T" connector. Pedal went right to the floor. Closed it and opened the rear "T" connector. Pedal was hard with only an inch of travel, yet fluid was squirting out. Pedal did not go to the floor.
This seems like a two part problem. It seems like fluid is being diverted to the front brakes and the front pistons are frozen.
Before I go tearing it apart, what do you guys think?

Lakota said:

It seems like fluid is being diverted to the front brakes and the front pistons are frozen.
Before I go tearing it apart, what do you guys think?

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Lakota,
Is it parked outside?

BoB

Parked right out front in the sandy driveway. We had rain here everyday for almost a month. Could that have caused a problem?

Sometimes rust isn't so good!

Lakota said:

Parked right out front in the sandy driveway. We had rain here everyday for almost a month. Could that have caused a problem?

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Lakota,
I had the same problem on the Daytripper. It has 4 wheel disc's & am now in the process of replacing 3 of the calipers... they're cheap & it's just easier. Thank goodness I have a place to keep it inside now!!! This is the 1st week in a couple of months it *hasn't* rained.

BoB

I'll make more tests today. The brake lines were left open for months. I'll open up the bleeders and if I have a good flow, then I'll know for certain that the pistons are frozen. I can't see how rust can get in there, that's a sealed unit. There's a rubber "O" ring on the piston so there's no metal to metal contact in the cylinder. Maybe a good whollop with a BFH will straighten it out.
When I swapped out the rearend, I replaced all the brake parts. I do remember one of the old brake cylinders had a blown seal and had leaked fluid everywhere. I forgot to reset the combo valve, I wonder if this is why the fluid is being diverted to the front brakes?

Update:

I checked all the lines, all clear. Rear brakes are working properly and grabbing. Believe it or not, the front brakes are actually working. There's still only about a 2 1/2" pedal travel. I'm beginning to think my rear brakes are not adjusted right. Too tight ???

Check out the current Rod and Custom magazine. There's a whole article about trouble shooting brakes. If I had had that article, I coulda trouble shooted the brakes before I sold it.

Will do!

gassersgarage said:

Check out the current Rod and Custom magazine. There's a whole article about trouble shooting brakes. If I had had that article, I coulda trouble shooted the brakes before I sold it.

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Gasser,
Thanks... I'll go ck that out this weekend!

BoB

could it possibly be a wrong master cylinder meby

could it possibly be a wrong master cylinder meby

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Nope...Frame, brakes, M/C, and combo valve are all 89 Chevy S-10.

I remember doing the rear brakes. I tightened them until the wheel stopped moving, then backed off a few clicks. I think I was supposed to back off a full turn, or 10 clicks.

I don't think they are adjusted wrong. If I'm thinking correctly they set themselves everytime you brake in reverse. My bet would be with that combo valve you're talking about.

I've forgotten so much about brakes. I used to do all my own brake work. But discovered that having a shop do them is a little costly in the beginning, but they're done right and if anything goes wrong, I can take it back to them and get it repaired free. Not only that, but if I have an accident and the brakes are at fault, My butt is covered.

Could be combo valve. It seems strange. When I open the rear bleeders, fluid comes out, but I still have a hard pedal.

Yup, it was the combo valve. I bypassed it by hooking the lines directly to the M/C, brake problem went bye-bye.