Need help with brakes

[My84TType]

Can someone tell me how to adjust a Brake Master Cylinder pushrod! I recently replaced the brake Hydro Booster and the Master Cylinder on my 84 Ttype, now the master cylinder will not seat flush against the brake hydro booster because the master cylinder pushrod end is sticking out little too far. I have no idea how to adjust the pushrod. The pushrod end that is sticking out turns left and right, however, it will not go in or out. The rod that comes out of the backside of the brake hydro booster and connects to the brake pedal also turns left and right but it will not get shorter or longer. What’s wrong here? This is the first time I am replacing these two units and I can’t remember if there was a spacer behind the brake hydro booster unit where seats against the firewall. I am anxious to get this car back on the road again, as it has been sitting for almost eight months because of brake problems and I really missed driving it. Help help!!

 

[REDS HOT AIR]

you are talking about both ends of the booster.....

from what i gather is if you put the master cyl up on the booster the center piece (plunger) is hitting the rod sticking out the booster

now does that happen with the other rod not hooked to the pedal?? or only if its hooked to the pedal

 

[My84TType]

Originally posted by REDS HOT AIR
you are talking about both ends of the booster.....

from what i gather is if you put the master cyl up on the booster the center piece (plunger) is hitting the rod sticking out the booster

now does that happen with the other rod not hooked to the pedal?? or only if its hooked to the pedal

 

[My84TType]

Thanks, good point, I left out one small detail. Yes, if I disconnect the rod from the brake pedal, the master cylinder connects to the booster just fine, however, the rod will not connect to the brake pedal anymore.

 

[REDS HOT AIR]

screw the brake light switch and cruize control switch out a lil and it should let the pedal come forward more...

that would be the easiest way

check it out and see what happens and post back

 

[HOTSIX]

Do you have regular old vacuum assisted brakes or that damn Powermaster system or Hydraboost system (uses pwr steering pump + lines)?

I converted my Powermaster system on my '85 GN to regular vacuum brakes two months ago. What a relief...

The only problem I had with my plunger was that it wasn't lining up with the
brake pedal. If you bench bled the system (which ya usually should depending on ur brake problems...) then just make sure the plunger is coming back out when you bleed it...if not - defective plunger/master cyl i'd say.

If thats ur problem - hope this helps. Like I say...I got rid of the troublesome Powermaster...it sucks..plus it's a fortune to replace or fix. If ya got one with problems...do yourself a favour - get a good old G Body vac assist brake booster / master cyl combo. The conversion is on gnttype.org. It's not as hard as I thought.

 

[Mike70gtx]

I just started having problems with my 84 GN. What type of system will be on the 84? Is there some info on gnttype.org?
I do know if I hit a water puddle just right, I lose my power steering and my brakes for a few seconds.
Symptoms now are loss of fluid in forward chamber and not much pedal left and brake light comes on a bottom of pedal.
P.S. Hope you don't mind me jumping in on this thread.
thanks

 

[My84TType]

Regarding the brake and the cruise control switches, they are both removed, the brakepedal freely moves all the way forward but it won't allow the plunger to hook up. It needs at least 1/2 an inch more to be able to connect the plunger, then the brake pedal need some play room, at least 1/2 to 3/4 inch. By looking at your hydro booster unit whare it mounts to the firewall, is ther a spacer there. May be that's what I am missing??

As far as what type of brake system I have. It's a hydroboost setup that works off of power steering's hydraulic fluid. Both units (Master Cylinder & Hydro booster) are rebuilt parts that I purchased them from Auto Zone.

 

[REDS HOT AIR]

sounds like they may have gave you one for a full size car or something..

do you have the old one to compare the rod lenth?

i dont think there is an adjustment to make on the rod

maybe go and pull another one at the parts store and see if yours may have been boxed or ordered wrong.

 

[My84TType]

I don't have the old one to compare, it was turned in as a core. I don't recall checking the rod length, I was mainly looking at the unit itself and the location of the hydraulic lines and the fitting sizes which they all matched. The problem is, that not too many places have these units in stock for me to compare. One other thing I am thinking about doing is maybe have a welding shop cut the rod and shorten it. I think this will work. See what happens. Thanks for your time, I will keep you guys posted.

 

[HOTSIX]

I'd be real hesitant to having the rod cut.

Not when your dealing with something like brakes anyway.

I still go with get rid of that old Hydroboost system - convert to vac brakes. Heck your doing the whole job anyway.....installing etc

 

[My84TType]

Ya, I know what you mean about welding. I had no idea that the vac brakes would work on these cars, otherwise I would have changed it. I have spent around $200 on the HB & MC. I will have to take mine out and call around to see if someone has it in stock and hopefully find one with a shorter plunger. Thanks, I'l keep you posted.