My Brake Light Keeps Coming On When I Put My Foot On The Brake The Light Flickers.need Some Help .mikeson2@sbcglobal.net 847 870 -0370.1987 Buick Grand National 16k Miles
the '87 GN (and other 86/87 TurboRegals) used a brake system called the Powermaster that is known to develop problems no matter what the mileage or use the car has seen. Basically - since the turbo engine develops little vacuum (actually negative vacuum which is boost under load) they went with a system that uses a pump and accumulator ball to store vacuum for brake applications. Ever hear that buzzzing noise after you step on the brake a few times ?? thats the pump developing vacuum for the accumulator ball so you have brakes the next time you hit the pedal. Anyway - Im willing to bet your brake lite problem has to do with the pedal "resting" too far down because the powermaster isn't working properly. I'd do a search on one of the turbo buick sites like www.turbobuick.com or www.turbibuicks.com
Usually this is an indication of the accumulator ball / bowl being bad. :spank: Here's a good site with alot of look and read info with a link to the brakes page. http://www.gnttype.org/techarea/brakes/brakespage.html Kirbans is a good source of powermaster parts and rebuilt units, although not cheap. https://secure.mysuperpageshosting.com/kirbanperformance.com/index1.htm They sell on ebay also with some good deals too. http://search.ebay.com/_W0QQfgtpZ1QQfrppZ25QQsassZkirbanperformanceQQssPageNameZSTRKQ3aMEFSQ3aMESOI If fixing on the cheap and not worried about keeping the car stock looking alot of guys install vacuum brakes from other similar year G body cars with no problems. Good luck. :beer
I'm not sure what does what. But I do know what a complete brake failure looks like on a GN. I bought a new one in '87 and with 15k on it mine failed with no warning. My entire engine compartment was covered with brake fluid and had no brakes at all. My wife was driving and was able to coast to a stop. Very lucky. I would suggest diagnosing/fixing before driving too much. -Mike
Several years ago I purchased a rebuilt unit from Advanced Auto for about $150. It came with a lifetime guarantee. I have replaced it twice since then with no questions asked by Advance Auto. The price has gone up since I bought mine, but I think you can still buy one for around $300. One of the best investments I ever made. Whenever I have any kind of trouble with the powermaster out it comes and I go get another newly remanufactured unit for no charge. Definitely the way to go. Some of the other auto parts stores may have the same deal. Just make sure it comes with a lifetime warranty and keep your receipt.
Mine does the same thing (blinks the light). The brakes seem fine, and the accumulator has been replaced, but it still does it.
That's right about the accumulator; but no longer available stock; Kirban has a reproduction one. I got entire remanufactured one from Advance Auto in 1995 (The actual customer did not have his core or the money at that time. Talk about being in right place at right time: VISA to MY rescue; He couldn't pay for it. Having already been ordered and received, they were glad to sell it to me.) but it is special order item now from A-1 CARDONE; Part number 529702. available various sources; Rockauto.com lists for 397.79 plus 75 core, total 472.79. prices going up up up. i will be converting to power brakes as used on 1989 turbo trans ams (same basic drivetrain, they used vacuum system tee'd off top block on throttle body (must get aftermarket vacuum block from kirban/ poston/ others) Piece of mind is having reliable brakes. Master Power(ha ha) sells entire conversion from powermaster system to vacuum system, but i robbed ENTIRE system, pedal and all, from salvage yard INTACT. Get correct plugs for lines. Moisture is enemy to brake systems. Good luck
By the way, the larger of three black relays (25527402) that controls the powermaster, is discontinued... don't know of any replacement or other relay in its place...another reason to convert to vacuum brakes. Be sure to install at least one new check valve in the line, and an vacuum accumulator canister, for more reserve vacuum. I have heard of some people using an electric vacuum pump like used on leveling systems, but no experience there. Good luck; the parking brake is all you got when it finally gives out; Only about 20-25% braking capability then.
