R8rPhan
Full Access Member
- Joined
- Feb 5, 2017
- Posts
- 452
- Reaction score
- 42
- Location
- California
- First Name
- Mark
- Truck Year
- 1973 (1979?)
- Truck Model
- C10 long bed (Frankenstein truck)
- Engine Size
- 307
Okay, so it's not the push rod length.. I took the mounting nuts off the master cylinder, and when I push on the pedal, I can feel it being pushed off of the booster (and hear it drag on the studs) within about a quarter inch of pedal travel... So that's eliminated...
I don't think it's the rears, but not sure.. I think there is an issue with the fronts... either application (mismatch of what the MC puts out and the calipers need), or the proportional valve (a distinct possibility), or one of the calipers (since it pulled to the right before this all started and still does, that wins the 'most likely' award right now)...
As far as the proportional valve goes, there is a quarter inch line that goes from the front side of the MC to the valve, and an eighth inch line from the rear port of the MC to the valve, then a quarter inch line that goes out of the valve to the rear brakes and two eighth inch lines that go to the fronts (one to the left and one to the right)...
I'll bleed everything again and check that left caliper/pads before I play with the P valve.. I also need to figure out why it's so hard to push fluid to the rears when bleeding.. Think I'll pull the lines off of the wheel cylinders (and go ahead and replace the other back one) and try pushing fluid through it then.. (maybe a blockage???)..
That P Valve looks like a beotch to replace, so I hope I don't have to go there.. Was hard just to get my hand in there to push the reset button...
So anyway, next break in the weather is Monday.. I better start working on getting a ride into town to take care of what business I need to do this week, and I'll keep researching and learning..
But... I got the new thermostat in, and redid the temp sensor, and now the temp gauge works and the truck warms up nice and quick and isn't running cold anymore.. Should be easier on the engine and improve mileage some..
Figured out a mounting place for the intermittent wiper module I bought, removed the circuit board mounted pot from it and extended it with some ethernet cable so that the module can be mounted under the dash near the ashtray and the pot can be mounted right next to the stock wiper control... Made up a little harness with a couple turn signal indicator LEDs because the ones in that digital dash I bought stopped working (and I don't want to mess with having the assembly replaced right now), so I can install them in the dash gauge cluster bezel, and I won't be driving around with my turn indicators on anymore... I can put the LEDs and the wiper control in over the next couple days...
I'll get the brakes fixed before long, if I have to replace every damn part in the system to do it (including the booster/MC I just put in)..
But as soon as weather allows, I'm gonna pull the wheels off again and get to the bottom of all this, one way or the other... In the mean time, I'm gonna try to research/compare caliper piston sizes, wheel cylinder sizes, and master cylinder piston/stroke to try and eliminate a mismatch issue... I kinda doubt that's the issue though, as I would expect it to do 'something'... I barely have brakes at all.. eBrakes work great though..
I don't think it's the rears, but not sure.. I think there is an issue with the fronts... either application (mismatch of what the MC puts out and the calipers need), or the proportional valve (a distinct possibility), or one of the calipers (since it pulled to the right before this all started and still does, that wins the 'most likely' award right now)...
As far as the proportional valve goes, there is a quarter inch line that goes from the front side of the MC to the valve, and an eighth inch line from the rear port of the MC to the valve, then a quarter inch line that goes out of the valve to the rear brakes and two eighth inch lines that go to the fronts (one to the left and one to the right)...
I'll bleed everything again and check that left caliper/pads before I play with the P valve.. I also need to figure out why it's so hard to push fluid to the rears when bleeding.. Think I'll pull the lines off of the wheel cylinders (and go ahead and replace the other back one) and try pushing fluid through it then.. (maybe a blockage???)..
That P Valve looks like a beotch to replace, so I hope I don't have to go there.. Was hard just to get my hand in there to push the reset button...
So anyway, next break in the weather is Monday.. I better start working on getting a ride into town to take care of what business I need to do this week, and I'll keep researching and learning..
But... I got the new thermostat in, and redid the temp sensor, and now the temp gauge works and the truck warms up nice and quick and isn't running cold anymore.. Should be easier on the engine and improve mileage some..
Figured out a mounting place for the intermittent wiper module I bought, removed the circuit board mounted pot from it and extended it with some ethernet cable so that the module can be mounted under the dash near the ashtray and the pot can be mounted right next to the stock wiper control... Made up a little harness with a couple turn signal indicator LEDs because the ones in that digital dash I bought stopped working (and I don't want to mess with having the assembly replaced right now), so I can install them in the dash gauge cluster bezel, and I won't be driving around with my turn indicators on anymore... I can put the LEDs and the wiper control in over the next couple days...
I'll get the brakes fixed before long, if I have to replace every damn part in the system to do it (including the booster/MC I just put in)..
But as soon as weather allows, I'm gonna pull the wheels off again and get to the bottom of all this, one way or the other... In the mean time, I'm gonna try to research/compare caliper piston sizes, wheel cylinder sizes, and master cylinder piston/stroke to try and eliminate a mismatch issue... I kinda doubt that's the issue though, as I would expect it to do 'something'... I barely have brakes at all.. eBrakes work great though..
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