Hi all, I've got a few questions about a truckI just inhereted. I figured this would be the right place to ask.

It's an 83 f-100. I have no clue what the original motor was, but now it has got a 351w in it. This is a truck my grandfather was trying to finish, btu he passed away a week ago. The motor he put in I believe has forged pistons, reman rods, unknown specs crane cam, edelbrock performer high rise, edelbrock carb. unknown size. the truck was originally an automatic, but is now I believe a 5 speed with an aftermarket scattershield/bellhousing. It also has a 9" rear with 3.50 gears. I know it's a weird and truely frankenstein truck. But everything is well done, and should be fun and reliable.

On to the questions. Today I put a new master cylinder on the truck. I bench bled it. And I got in mounted and bled the rear brakes no problem. When I went to open the bleeders on either front caliper, no fluid or air would come out. I pulled the bleeders and cleaned them out, but nothing would still come out of either side. Is there some trick to bleeding these brakes? Or do I have two bad front calipers? I do have quite good brake pressure so I may just drive it like this for awhile.

Now for the exhaust. The truck has factory exhaust manifolds. I need the flanges that bolt the downpipes onto the manifold. I can't seem to find them online. Does anyone have a good source for these without going to a salvage yard?

Thanks guys, Jason

 

Nevermind about the brakes. I used the search button and found out my rubber lines are probably collapsed.



bump for some advice on exhaust

 

Or the shuttle valve in the brakes is stuck to one side....

Any decent muffler shop should have a flange for you.

 

Pardon my ignorance, where is the shuttle valve? And how do I adjust it?

 

No adjustment, if you loose pressure in one side of the M/C (front or rear) it can slide all the way to one side and become stuck.
I've never experienced it myself, but it was recently mentioned in a thread.
I could try "search" if you can't find mention of it....

 

Is it part of the proportioning valve on the frame rail?

 

Maybe I'm using the wrong term.
Yes, I believe it is.
Let me see if I can find the thread.....
It was about an inability to bleed the brakes.

 

Perhaps I'm FOS, I can't find it anywhere.
I have to get better at selecting search parameters...

Sorry.

 

Hey no problem Jim. I appreciate your input and I will try to find more info on a shuttle valve. If anyone else has an opinion please share.

 

You can tap the master cylnder very lightly with a rubber mallet and sometimes that will get the valve to release and slide back up. When I first got my truck I only had front brakes and no rear and had good pressure. Couldnt figure it out till my boss came and tapped on it a little and it released and all the sudden I had back brakes. For the exhuast, I got a part from a muffler shop that was actually like a new flange. Cost me 40 bucks for both sides and it works great.

 

The proportioning valve has a plunger that slides back and forth when pressure is lost in the front or the rear brake system. But all it does is activate a light, it doesn't block fluid flow. Some of the proportioning valves also have a plunger that you are supposed to push when bleeding the brakes, but I have never had to mess with it.

What I would do is loosen the brake line at the master cylinder that goes to the front brakes, and then push on the brake pedal. Some fluid should leak out. If it does, then work your way down to the front calipers, seeing if you have fluid. Possibly what happened on this project truck was that it has been towed at one time or another, and someone has crushed one of the metal brake lines going to the front.

 

Well guys I finally figured it out through research. I had to pull the little nipple out on the proportioning valve while bleeding the front brakes. I've also got the truck at the exhaust shop getting 2.5 turndowns done. Thanks for all the help and advice.

Jason