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Well, i'm stumped. I have read and been told that the braking system on the M8 and M20 vehicles are a biatch, but how bad could it really be , right? Well, I gotta say that they are the most difficult ones I have ever done and I have hit a wall with an issue that they have.
Rebuilt the MC..same one as a deuce, blew out all the lines and flushed them, replaced the two axle to knuckle rubber lines due to swelling internally and rebuilt the wheel cyls with updated parts. On assembly, gave the shoe clearance .010 all the way around. Rebuilt the hydraboost.
We have bled the pee pee out of them and I am positive that there is no air in the system...put a gallon through it yesterday alone. Here's the issue. If you step on the pedal, it goes to the floor, but not like it is full of air. There is definatly fluid resistance there. Let up, re apply and perfect pedal. Check this out. If you TAP the pedal, as in depress it 1/2 inch and let up..perfect pedal on the next stroke. All 6 wheels will lock upon the second application and release fine.
The pistons in the new style wheel cylinder kits are shorter than the old ones, but, once the fluid has filled the system, that shouldn't be an issue because the stroke of the MC piston will still pressurize the cylinders the same amount as with the old pistons, there is just more total volume, correct? There is freeplay in the pedal and it, the MC, is returning to the top of the stroke, no leakage from the wheel cyls.
I looked for kinked/pinched lines and saw none, that should cause slow application and release of 1 or more wheels, but it isn't doing that.
I thought that it might just need to be driven, so I took it for a spin around the museum grounds, it does the same thing. If you apply the brakes once using the pedal to the floor or the slight tap, it stops great on the 2nd application, release it, drive 50 feet, same thing, two pedal actions to stop. Any help or ideas will be greatly appreciated.
Rebuilt the MC..same one as a deuce, blew out all the lines and flushed them, replaced the two axle to knuckle rubber lines due to swelling internally and rebuilt the wheel cyls with updated parts. On assembly, gave the shoe clearance .010 all the way around. Rebuilt the hydraboost.
We have bled the pee pee out of them and I am positive that there is no air in the system...put a gallon through it yesterday alone. Here's the issue. If you step on the pedal, it goes to the floor, but not like it is full of air. There is definatly fluid resistance there. Let up, re apply and perfect pedal. Check this out. If you TAP the pedal, as in depress it 1/2 inch and let up..perfect pedal on the next stroke. All 6 wheels will lock upon the second application and release fine.
The pistons in the new style wheel cylinder kits are shorter than the old ones, but, once the fluid has filled the system, that shouldn't be an issue because the stroke of the MC piston will still pressurize the cylinders the same amount as with the old pistons, there is just more total volume, correct? There is freeplay in the pedal and it, the MC, is returning to the top of the stroke, no leakage from the wheel cyls.
I looked for kinked/pinched lines and saw none, that should cause slow application and release of 1 or more wheels, but it isn't doing that.
I thought that it might just need to be driven, so I took it for a spin around the museum grounds, it does the same thing. If you apply the brakes once using the pedal to the floor or the slight tap, it stops great on the 2nd application, release it, drive 50 feet, same thing, two pedal actions to stop. Any help or ideas will be greatly appreciated.