Finished up disc swap... now some questions

[crozetiga]

I just completed my disc brake swap and i have a few questions about some weird things. T

he first is question is about the brake pedal. I hooked up the 1978 booster/master cylinder assembly to the 1970 brake pedal and now the pedal sits alot lower. I still has enough travel so that it doesnt bottom out on the floor, It just looks weird with the clutch really high and brake pedal really low.

The 2nd question is that the brake pedal doesnt want come back up once it is pushed down. It has been bleed and it has stiffness to to pedal, it just doesnt want to come all the way back up once its down. I fabricated a spring bracket and spring to help it up as a temporary fix. What can i do to permanently fix the problem

Thanks in advance

Josh

[layedout72]

i believe there is a return spring u need, but it seems u made one. thats what ive gathered reading a couple threads about the swap.

[crozetiga]

I have one more question. To connect the booster to the brake pedal, there is a bolt. On both my truck and the donor truck, the little nylon bushing that takes the slack out was trashed. Is there anywhere that you can buy that or did you just fabricate something else so that there wasnt play between the brake pedal and the booster arm.

Let me know where or what you did to remedy the problem

Thanks
Josh

[mrsnicks]

There was a post similar to this somewhere.. the 1973 and up pedal does sit lower.. it was actually an advertised change to help in stop and go traffic... pedal sits lower and requres less movement and effort to step on....

Keith did a really good reply on it with a picture somewhere..... do a search you may be able to find it.

Patrick

[crozetiga]

I did a search and came up with this but didnt come up with my exact problem. Let me give more information

Here is my setup: 1970 3 speed F100 with brake booster and master cylinder from a 1978 f150. Connected the arm from master cylinder directly to the 1970 brake pedal. The nylon bushing that was on the bolt to connect the MC arm to the pedal was broken so I left it off, so there is a little bit of play in the connection between the 1970 pedal and the 1978 MC arm. If I can't buy the bushing (I looked at Dennis Carpenter and couldnt find it) I will drill out the hole and use a larger bolt to eliminate the play. I also dont really mind the lower pedal. these arent my main concerns.

I am more concerned about the fact that my brake pedal doesnt return all the way up. I have pretty stout spring on it but it still doesnt want to return up. It stops fine, and has a hard pedal but wont return up. I was wondering it has something to do with the booster (it and the MC donors from the f150) or if a leaky wheel cylinder in the rear may be to blame? Maybe I just dont have the spring attached in the right spot. For those who have done this, where did you mount the return spring? Should I use the 1978 pedal? (it is an automatic, will that make a difference?)

I just cant drive my truck right now cause I drove it to Home Depot the other day to get a lawn mower and right in the middle of the busiest intersection in my town, the brake pedal stuck down and went to take off and I about killed the clutch getting it to go. Once I figured out the problem, I have to put my foot under the brake pedal to lift it up before I take off which makes for some interesting coordination issues. (like I dont have any!!!)

Thanks in advance for any info you can help me with

Josh

[dotcentral]

I bet you could get that bushing in the "HELP" section of the autoparts store. If your local parts store doesn't have one of those sections, ask the counter guy for a bushing.

Carpenter's has them, pretty sure, if no one else does. You'll pay a premium for the DC name though.

Does it feel like the pedal is binding? maybe the lack of a bushing is doing that. Or possibly the older style pedal on a newer M/C since it 78 M/C is designed to travel less distance than your 70 brake pedal?

Try having someone push the pedal while your watching it. Watch it under the hood, in the cab, maybe you can findout if its hanging up one something. Good luck.

[fordman]

i'd try the 78 pedal and fix the leaky cylinder.

[cdeal28078]

I wonder if it is the adjustable pushrod needing adjustment. It had been a long time since I did this so bear with me.
The long pushrod that is about 1/4" has an adjustable end on it to. There are specs on the adjustments in the books about it, you can use it to adjust how much movement the pedel takes before the brakes come on.
I know that my brake peddle does'nt have any kind of return spring on it and it works just fine. So something is'nt right
Clint