Help! 86 Brk Master

[Marv02]

My Brake Master cylinder is bad on my 1986 I started toprice a replacement so far at Napa a new one $240.00+ a rebuilt $150.00 arebuild kit $130.00.
Yes I also thought it would been cheaper what other yearscan I use that will bolt up or Is there an aftermarket High performance one that willbolt up also for this kind of money might as well ask around and see if anyothers out there found a better bang for the buck.

 

[Marv02]

I ended up ordered a rebuild kit though GM Direct for $40.00.

 

[Hib Halverson]

When "rebuilding" the aluminum master cylinders on C4s, know that you cannot hone or otherwise abrade the bores if they are scored as we could do with the 82-earlier cars which had cast iron masters.

Disassemble the cylinder then inspect the bore. If it's scored, corroded or otherwise damaged, scrap the cylinder and buy a new one.

If you inspect it and find the bore free of any damage, then install the rebuild kit, flush the system and bleed per the FSM.

 

[Marv02]

I pulled the piston out cleaned checked the bore everything looks good.

Well this kind of a good thing I am fixing a oil leak as long it needs to be on Jacks to bleed the brakes anyways.

I thought it was a leaking rear main seal I lucked out it a bad oil pan gasket and I had a spare already.

I much rather pull the oil pan than pull the trans out to change out the oil seal.

When "rebuilding" the aluminum master cylinders on C4s, know that you cannot hone or otherwise abrade the bores if they are scored as we could do with the 82-earlier cars which had cast iron masters.

Disassemble the cylinder then inspect the bore. If it's scored, corroded or otherwise damaged, scrap the cylinder and buy a new one.

If you inspect it and find the bore free of any damage, then install the rebuild kit, flush the system and bleed per the FSM.

 

[Marv02]

I am tired of GM DIrect just seems like they say they stock a part but just about everytime I order though them they come back and tell me they dont have it.

I think they just lost a custormer.

I found a seal kit on Flee bay we will see if this works.