Brake system failure?
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These cars will wear you out! Both monetarily and patience wise! I'm dumb enough to have 3. I should put Hydroboost in 1 so I can have all 3 systems and make a logical deduction.
Really though, don't try to fix the PM through "normal" means if it's a 30 year old non maintained system. When I used to wrench for a living and everyone wanted to go fast, the first thing I would look at was brakes/suspension. If that was lacking, I wouldn't make it go faster. After all, it might be you I see in my rear view mirror
Funny thing is that the issues with this car have yet to bother me as much as those I had with my 71 Buick GS clone. My wife might say otherwise after today. With the 71 no matter how much $ I put into the car she just did not want to be happy and that's why I called her Christine before I sold her. Right now the 86 is known as Sue! LOL
I always wanted one of these cars so I am in it for the long haul but will have LOTS of questions as I move forward. I am very greatfull for this site and all the info available.
I always wanted one of these cars so I am in it for the long haul but will have LOTS of questions as I move forward. I am very greatfull for this site and all the info available.
Read, read, and read some more. Most of your questions will have been answered here already. I stalked the site 5 years before I became a member, and when I couldn't find the answer, someone here had it. I was very impressed with the "going fast with class" attitude of this site.
If I may add, TurboLou and AZGN on the West coast are superb, as is Richard Clark on the East coast. To quote Spoolfool2, Happy Spooling!
If I may add, TurboLou and AZGN on the West coast are superb, as is Richard Clark on the East coast. To quote Spoolfool2, Happy Spooling!
Kirbans has it inclusive
Update:
OK so today I took the car on the highway to a car show after replacing the 30 amp fuse last time and having NO issues for the last few weeks. Car was fine, arrived at the show at 10:00 am and parked her. Went to leave at 3:00 PM, started her up and the fuse blew right off and I never applied the brake. I replaced the fuse and about half way home after getting off the highway she blew again. I replaced the fuse and two minutes later she blew again. Got her home, let her sit for a bit, replaced the fuse for the 4th time and low and behold even after beating her up a bit around the neighborhood I could not get the fuse to blow. I have read the post on servicing the system as suggested and I admit I am guilty of not at least flushing the system but have not had the time and I did not see an answer to my question. I am however as a NEWBIE trying to gain a general understand as to why this happens. Is the pump just running too long? It never sounds or runs for the same period of time twice. Still considering a full bleed (if this might actually help), replacing the accumulator ball which was replaced sometime prior to my purchase (is there a way of checking it) prior to committing to a whole system change. I see there are many kits at Kirbans and on Ebay to convert for around $300 that change most everything including the brake pedal. However, I have been in a coupe of cars with the system changed and the brakes just don't feel the same when everything works as it should. My biggest question is can any of the above be done by a weekend mechanic or is it best left to a GN/T Type specialist?
Thanks
OK so today I took the car on the highway to a car show after replacing the 30 amp fuse last time and having NO issues for the last few weeks. Car was fine, arrived at the show at 10:00 am and parked her. Went to leave at 3:00 PM, started her up and the fuse blew right off and I never applied the brake. I replaced the fuse and about half way home after getting off the highway she blew again. I replaced the fuse and two minutes later she blew again. Got her home, let her sit for a bit, replaced the fuse for the 4th time and low and behold even after beating her up a bit around the neighborhood I could not get the fuse to blow. I have read the post on servicing the system as suggested and I admit I am guilty of not at least flushing the system but have not had the time and I did not see an answer to my question. I am however as a NEWBIE trying to gain a general understand as to why this happens. Is the pump just running too long? It never sounds or runs for the same period of time twice. Still considering a full bleed (if this might actually help), replacing the accumulator ball which was replaced sometime prior to my purchase (is there a way of checking it) prior to committing to a whole system change. I see there are many kits at Kirbans and on Ebay to convert for around $300 that change most everything including the brake pedal. However, I have been in a coupe of cars with the system changed and the brakes just don't feel the same when everything works as it should. My biggest question is can any of the above be done by a weekend mechanic or is it best left to a GN/T Type specialist?
Thanks
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If you are interested in determining why the 30 amp fuse blows intermittently and correcting the problem you may want to buy the PowermasterTroubleshooting and Repair book that Richard Clark and I wrote. It's available from Kirban Performance.
There is a troubleshooting flow chart on the subject of blown fuses. That failure mode could be due to a number of issues including a faulty ground connection on the Powermaster wiring harness to firewall. A bad fan relay could also blow Powermaster related fuses.
The book also walks you through steps for testing the major components, including the accumulator ball that you recently replaced. The tests can be done with common household items and tools.
There is a troubleshooting flow chart on the subject of blown fuses. That failure mode could be due to a number of issues including a faulty ground connection on the Powermaster wiring harness to firewall. A bad fan relay could also blow Powermaster related fuses.
The book also walks you through steps for testing the major components, including the accumulator ball that you recently replaced. The tests can be done with common household items and tools.
If you are blowing the fuse and don't have an obvious short to ground on the power lead then the short is internal. This happens because the pressure switch fails and the pump continues running when it shouldn't be. The motor overheats and the windings burn and short to ground. The fix is a new motor and pressure switch or replace the unit if you can't obtain a new motor
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TexasT
Texas, Where are you from
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Just be sure to pump the pedal(10 times) with the key off to relieve the pressure in the system before you work on it. Spraying high pressure brake fluid around isn't fun on any level.
As far as any special skilz to work on your brake system, it isn't rocket science but you do need to be able to properly bleed brakes. These cars are getting to be thirty or so years old and might not have had top notch anal maintenance so some things might need attention. When I did my hydroboost I bled it all out until I got clear fluid out of the bleeders. I know it hadn't been changed as I bought the car new. It was crusty and chunky and I had to pull and clean the bleeder screw several times on each rear wheel to get it to keep bleeding. I think the people who come and post they have a spongy pedal or the pedal drops either have a bad rebuild on the mc or they aren't getting all the air out of the system. I learned in the eighties on my GS that you just keep bleeding until you have a firm pedal. Air can be trapped and the mc if not bled properly before you start on the wheels just puts air from it into your system and you have the spongy pedal. Another thing I like to do when bleeding is put a 2x4 piece of wood under the pedal. My pedal pusher is usually one of my kids or the wife if I can talk her into it and they will put the pedal to the floor and this can overstroke the mc and put air into the system too.
Mu result is brakes that'll put you into the windshield on a panic stop. Brakes are way better than any powermaster equipped car I ever drove. I have confidence it will stop now.
As far as any special skilz to work on your brake system, it isn't rocket science but you do need to be able to properly bleed brakes. These cars are getting to be thirty or so years old and might not have had top notch anal maintenance so some things might need attention. When I did my hydroboost I bled it all out until I got clear fluid out of the bleeders. I know it hadn't been changed as I bought the car new. It was crusty and chunky and I had to pull and clean the bleeder screw several times on each rear wheel to get it to keep bleeding. I think the people who come and post they have a spongy pedal or the pedal drops either have a bad rebuild on the mc or they aren't getting all the air out of the system. I learned in the eighties on my GS that you just keep bleeding until you have a firm pedal. Air can be trapped and the mc if not bled properly before you start on the wheels just puts air from it into your system and you have the spongy pedal. Another thing I like to do when bleeding is put a 2x4 piece of wood under the pedal. My pedal pusher is usually one of my kids or the wife if I can talk her into it and they will put the pedal to the floor and this can overstroke the mc and put air into the system too.
Mu result is brakes that'll put you into the windshield on a panic stop. Brakes are way better than any powermaster equipped car I ever drove. I have confidence it will stop now.
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TexasT
Texas, Where are you from
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Nos4gn, kirban not sure about other places. I got mine from the dealer when they had the recall. This was after they canceled my warranty for breaking too many transmissions so I told them they couldn't put it on.
626gn
Well-Known Member
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Sometimes (not always) brake fluid in the switch connector is a sign of a bad switch. Replacing the switch is easy enough. Just depressurize the system by pressing the brake pedal (in key off position) until you get a hard pedal. It may take 5 or more pumps. Disconnect the plug on top the switch, unscrew the switch, then screw your new switch in and reconnect the plug. IIRC, you may have to reuse your o-rings...
The motor on the other hand is harder to come by as they don't make them anymore to my knowledge. Finding someone who salted one away is not easy and if you find one, will be expensive. You could always buy a used one but you'd be rolling the dice on how long it will continue to work, if it works at all.
You're at a point where you need to make a business decision. Continue to throw parts and money into your current Powermaster and hope for the best until it fails you again, buy a whole new PM setup for $600-$700? and hope it doesn't fail you, or heed the advice given to you at least 4 or 5 times in this thread and go vacuum (~$300) or hydroboost. Whatever you choose, please stop driving the car the way it is now. You and others around you may not be as fortunate as you have been next time.
The motor on the other hand is harder to come by as they don't make them anymore to my knowledge. Finding someone who salted one away is not easy and if you find one, will be expensive. You could always buy a used one but you'd be rolling the dice on how long it will continue to work, if it works at all.
You're at a point where you need to make a business decision. Continue to throw parts and money into your current Powermaster and hope for the best until it fails you again, buy a whole new PM setup for $600-$700? and hope it doesn't fail you, or heed the advice given to you at least 4 or 5 times in this thread and go vacuum (~$300) or hydroboost. Whatever you choose, please stop driving the car the way it is now. You and others around you may not be as fortunate as you have been next time.
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626gn
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If you decide to stick with the PM you should NEVER allow your brake fluid to go black like oil. It needs, at minimum, yearly changes. I do mine every six months or so together with an oil change. Once you got clean fluid in there you don't need a full bleed every time you change the fluid. Just depressurize the system and suck the old fluid out of the reservoir with a syringe or turkey baster. Fill with DOT 3 or 4 (I like 4) to the fill lines inside the reservoir. This is important as most people don't know what the proper fill levels are. When the system is pressurized the front passenger side chamber should appear less than a third full.
If your passenger side chamber is currently more than a third full I would suggest you take some fluid out before depressurizing. Otherwise the chamber will overflow as you depressurize and brake fluid will seep or shoot out making a big mess. If it gets on your paint, well we all know what happens then...
If your passenger side chamber is currently more than a third full I would suggest you take some fluid out before depressurizing. Otherwise the chamber will overflow as you depressurize and brake fluid will seep or shoot out making a big mess. If it gets on your paint, well we all know what happens then...
Thanks for the info guys. I do agree the car is unsafe at the moment and will probably look into swaping the system. Like I said I was trying to understand the flaws of the system and cause of my particular issue. If the switch could be had for cheap I was considering giving it a try just to see what happens. I see them going for $100 but I do not wish to through good money after bad.
In doing some reading into converting to a regular vacuum system as suggested I see that a conversation its not recommended if there are certain modifications to the engine. Would any of these cause an issue?
TA49 turbo
36# injectors
100# valve springs
turbo tweak chip
In doing some reading into converting to a regular vacuum system as suggested I see that a conversation its not recommended if there are certain modifications to the engine. Would any of these cause an issue?
TA49 turbo
36# injectors
100# valve springs
turbo tweak chip
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