Last post on Feb 29, 2012 at 3:08 PM
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Brakes, Electrical, Engine, Coupe, Convertible, Hatchback, Truck, Sedan, Wagon, SUV, Van
This topic will hopefully allow the more knowledgable of our community members share what they know with those seeking a good explanation for "how things work" in a car; or, this is a good place for equally knowledgable people to discuss the finer points of a technology.
#382 of 401 Re: 05 Impala Transmission [sk2b1]
May 22, 2009 (12:51 pm)
Try Lubegard Red... or the pre-flush conditioner.
#383 of 401 Brakes start fine, then start dragging progessively worse
Jun 03, 2009 (8:51 pm)
Our '97 Montero Sport just started having a brake issue. When you first get into it, the pedal is fine and everything works great. After a few miles, the brakes start dragging and it gets increasingly worse until you just pull over. The first time it happened to our son and he was only about 5-8 miles from our house. He was getting a couple of tanks of propane filled. By the time he was done paying, it was okay again. He returned home and told me about it. I took it out for just a bout 5 or so miles and saw no symptoms. The next evening, we took it out for another drive Round trip had to be about 30 miles, but we did have a 10 minute stop in between. We did not really notice the dragging, but we did notice the pedal got much higher (very little play). It could have been dragging a little, but I had my wife driving because it is her car and thought she would notice the differences better. The only thing she noticed was the decresed play in the pedal. My son was again driving it to school the next morning and he only made it about 7 miles before they started dragging really bad. I went and took him to schood. We were going to have it towed, but by the time we got back it was again normal so we drove it home. Since I was unsure of which wheels may have issues, I went out that evening and I jacked up all 4 corners and they turned freely. Tonight I drove the car around here for maybe 5 or so miles. I did some start and stops and some normal braking, but I did not drag the brakes on anything out of normal. I noticed the pedal play getting shorter so I headed towards the house. By the time I got home, it was dragging pretty bad. I then jacked up all 4 corners and every wheel was locked up if you were just trying to spin by hand. Since it is pretty much all 4 wheels reacting the same, I am thinking the master cylinder or the booster. Anyone experienced this before. I wouldn't think it would be the rubber lines since it is affecting all 4 wheels equally, but I am guessing there could also be a valve that is getting clogged and acting like a check valve.
#384 of 401 Re: Brakes start fine, then start dragging progessively worse [kbc6313]
Jun 03, 2009 (9:17 pm)
Well, I would have said a rubber brake hose is collapsing inside and not relieving the pressure. But, when you said all for wheel seem locked - I don't know.
#385 of 401 Re: Brakes start fine, then start dragging progessively worse [kbc6313]
Jun 04, 2009 (1:32 am)
I don't know anything specific to your model vehicle. However, the symptoms are common and similar to defective wheel calipers, except normally you would detect the problem on the fronts (which do the majority of the braking).
Moisture and crude gets into the brake system, and collects down in the calipers, behind the pistons. It can corrode the inside of the caliper. The problem usually surfaces after a brake pad change, when the pistons are pressed back into the caliper (required to make room for the thicker brake pads). Pressing the piston back, forces the piston back onto the area of crude and corrosion, and the piston begins to stick and not 'float freely' as required.
Putting on the brakes puts tremendous hydraulic pressure on the piston, and it is able to force the piston out okay. However when you take your foot off of the pedal, the piston isn't able to float back and the pad stays engaged with the rotor. Your rotors start to get very hot (and can warp), you can usually smell the overheating, and the brakes stay engaged. Pads wear out quickly.
I usually replace the calipers with every 2nd set brake pad change. They're cheap enough, easy to do. Flush the fluid with every change.
How old are those calipers? and how often have you flushed the brake fluid?
If this was my vehicle, I'd do a complete brake job replacing all calipers, pads, fluid, and rotors.
#386 of 401 Re: Brakes start fine, then start dragging progessively worse [kiawah]
Jun 04, 2009 (4:10 pm)
Thanks, but I have looked into both the rotors and calipers. If it was just one or even two different wheels, I would think the calipers could be the issue. I have had those go bad on other vehicles in the past. The fact that I can recreate the problem and they always work fine for a short while then they all fail at the same rate tells me that one of the major components must be failing. That is only a logical guess, but it does not seem to be related to one or two of the wheels and their components.
#387 of 401 Re: Brakes start fine, then start dragging progessively worse [kbc6313]
Jun 04, 2009 (4:40 pm)
Well okay. If you have moisture and crud in the hydraulic, you could easily have multiple calipers failing. They'll turn when they are cold, but as they're driven they'll heat up the rotor which will expand, and they'll drag more and more. The more they drag, the hotter they get, the tighter they get.
You haven't indicated that you've done previous maintenance of flushing hydraulics or replacing calipers, so for a vehicle as old as that is.....those calipers would be my first suspect. Compare the color of the hydraulic fluid with new clear fluid. Calipers are a simple change, and you need to start with the basics
Good luck with whatever you decide to do.
#388 of 401 Re: Brakes start fine, then start dragging progessively worse [kbc6313]
Jun 04, 2009 (10:47 pm)
If all 4 wheels are having a problem at the same time, I also feel there is a problem upstream from the wheels.
Like the ABS system is completely screwed up. Is there a Check Engine Light turned on? If so, have you checked the code? Or, is the Brake Light turned on, or some warning regarding the brake system? On some cars, the ABS braking system is a separate 'code setting' system from the main Check Engine Light, and sometimes even has a separate plug to access the codes.
#389 of 401 Re: Brakes start fine, then start dragging progessively worse [bolivar]
Jun 05, 2009 (5:34 pm)
I do not have any ABS or warning lights of any kind. The more I think about it, I am leaning towards the booster. The fact that the pedal decreases in travel at the same time the pressure is also being applied to the calipers makes it appear that I have an increasing pressure issue. I stuck piston in the master cylinder could cause the brakes to drag, but I would not think it would also affect the brake pedal pressure. I am definitely far from an expert or I would know the problem. That is why I am seeing if anyone else has experienced such a thing before. I know that as everything heats up the issue will just get worse, but it is never driven long once the dragging is initially felt, It gets progressivly worse very quickly once it starts and is somewhat intermittent at first. I can re-create it more quickly now. I haven't fluhed the system and I will do that jsut because it can't hurt anything and is probably not a bad idea in this case. If anyone has anyone has any more thoughts, I am always willing to learn. Thanks
#390 of 401 Re: Brakes start fine, then start dragging progessively worse [kbc6313]
Oct 31, 2009 (11:59 am)
Brake booster or master cylinder.
Are you sure all 4 wheels are dragging or locking up? A corroded caliper piston (I had one of those) may not allow the brake pad to retract from the disc, but that would keep the brakes on 2 of the 4 wheels pressurized. Same thing for a caliper slide or corroded surface the caliper slides on.
Yes, you should flush the system. But if something has already been corroded, flushing will probably not fix the problem.
#391 of 401 How to degrease an engine?
Dec 13, 2009 (6:45 pm)
Let me preface by saying I have never rebuilt an engine before, but I'm not afraid to try! That said, I've removed the engine from my 1969 Triumph and have also removed nearly everything from the block itself (alternator, distributor, carburetors, oil filter, fuel pump, rocker cover)...
But the engine is still really gunky, so before I begin to dismantle the major engine parts I want to clean it well. The Hanes manual is very careful to point out that you should clean the engine before it is dismantled because you don't want any of that gunk getting in your engine. Ok... But with so many other parts removed, chemical cleaner or gunk is bound to get inside the engine.
How careful do I need to be to not get cleaner or gunk inside the engine? Is this even a problem since I am going to strip the engine all the way down and will have a chance to clean it as I go?