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So from my last thread I finally got the hydroboost working. However, it feels like the car is dragging when I go to let off the brakes. Have you guys shimmer the MC to the hydroboost, or did I adjust something wrong? I set the depth and made a little adjustable pushrod. I figure that might be off a bit. So what might have I done wrong? I put about an 1/8 of washers as a shim, seems to be a little better. Any ideas?
You do need to make sure the brake pedal isn't all the way up. When the system heats up it expands somewhat and if it cant push the pedal up it presses the other way and pushes the piston in, applying the brakes.
M
If it's always dragging then it'll get even worse when it heats up
On mine, the pushrod ended up here
but that's not meaning yours would be the same
M
I'm going to pop it out again. I. Using a willwood MC. I used that H looking tool to figure it out, thought it was perfect. Only other thing, I have the return line plumed in to the brass T at the 90, rather than the straight through. Would that do it? It feels like it's slow to release
atthemattin
Is your adjustable pushrod readily accessible? Or room for more shims? If so I'd make the adjustment. A friend of mine had his brakes "apply" just from regular warming up because he was so close to the edge of applying them..... he gave himself some more room and had no additional problems. Not a terribly big deal for him but if I remember right he did have to wait to cool down to drive home (luckily he wasn't too far from home).
Do you have any project pics? I am also considering Hydroboost.
Originally Posted by atthemattin
So from my last thread I finally got the hydroboost working. However, it feels like the car is dragging when I go to let off the brakes. Have you guys shimmer the MC to the hydroboost, or did I adjust something wrong? I set the depth and made a little adjustable pushrod. I figure that might be off a bit. So what might have I done wrong? I put about an 1/8 of washers as a shim, seems to be a little better. Any ideas?
The rod should have about .010-.020 clearance between the MC and the HB and then the pedal itself should be at least 1/4" - 1/2" down from it's high limit, this is the clevis to brake pedal
I ran a Tee fitting for a couple of years without issue and then later when I had the PS pump out I added another return fitting but either way was fine. On the Tee, the steering goes straight through and the hydroboost return comes in at the 90 deg side.
Probably nothing new for you but here was my install
The rod should have about .010-.020 clearance between the MC and the HB and then the pedal itself should be at least 1/4" - 1/2" down from it's high limit, this is the clevis to brake pedal
I ran a Tee fitting for a couple of years without issue and then later when I had the PS pump out I added another return fitting but either way was fine. On the Tee, the steering goes straight through and the hydroboost return comes in at the 90 deg side.
Probably nothing new for you but here was my install
The rod that goes between the MC and the HB unit needs a tiny (0.01"-0.02") gap which you would have set checking with that H tool otherwise it's always pressing the brake slightly.
The brake pedal must be set (with the clevis) so the pedal isn't in the "all the way up" position. If you pulled the pin, the pedal should be free to move UP some.
Usually the return hose only causes problems during braking while turning type of thing.
If you add washers between the HB and the MC and it fixes the problem then it's either the rod of the brake pedal.
I don't know how your clevis is attached to the HB, I threaded mine so it's adjustable, If yours is as well, I'd pull the clevis pin and make sure the pedal it's at the top of it's travel. If it's ok, then shorten the HB/MC rod a little (not too much, then there will be a dead zone in the brake pedal movement)
M
The rod that goes between the MC and the HB unit needs a tiny (0.01"-0.02") gap which you would have set checking with that H tool otherwise it's always pressing the brake slightly.
The brake pedal must be set (with the clevis) so the pedal isn't in the "all the way up" position. If you pulled the pin, the pedal should be free to move UP some.
M
Gonna check the clivis. I was definitely to long on the pushrod. But what I noticed is that my boost extends when the motor is running by maybe a little under 1/8. Is that normal?
Not sure what you mean? What extends? The MC/HB rods moves 1/8" when you start the car? That shouldn't really move at all. Brake pedal dropping when starting is usually a restriction or faulty HB unit
Not sure what you mean? What extends? The MC/HB rods moves 1/8" when you start the car? That shouldn't really move at all. Brake pedal dropping when starting is usually a restriction or faulty HB unit
M
So yeah. I got maybe an 1/8 that extends when it turns on and fills up. I'm probably just going to set it to where it extends and then just leave it at that. But I'm not sure why it would do it. Would that be do to the peddle being to high? This happens when it's completely cold
Air in the system or restriction in the return line will also do that.
You could check the return fitting in the HB that goes to the hose, there's a small orifice in there that can get clogged with gunk. The Tee line should be large and free so not likely a problem, make sure the hose isn't pinched or kinked
Re-bleed the HB/steering, take your time
M
Air in the system or restriction in the return line will also do that.
You could check the return fitting in the HB that goes to the hose, there's a small orifice in there that can get clogged with gunk. The Tee line should be large and free so not likely a problem, make sure the hose isn't pinched or kinked
Re-bleed the HB/steering, take your time
M
Yeah I'm thinking a little air might be it. Gonna jack it up and rotate it. What size brass T are you using? Also, appreciate the help. Thanks
Gotta go see what Tee fitting size I have in it. I use fuel line for the return. I'm wondering if I just need to drive on it more. When you release the brakes, it's crisp and let's go instantly like vacuum?
Shining hydroboost to mc
