Need help working on my AE86

[NCMR2]

I have run into a couple of potential problems with the Corolla that I need to look into.
1) When I get on the brakes hard, the car dives back and forth as if there is not equal pressure on all four rotors. Also, every now and then, the right rear caliper will stick and releases in a short time, and usually with a little taps from the brakes. What do I need to look into here? Bleeding maybe? The pedal stays pretty firm and the master cylinder is still good.

2) On my "test drive" tonight, the radiator began to overheat and spew water out the top/side of the radiator, not the cap. What do I check to see what could be causing this? This was the first time it has overheated, but also was the first time I ran the motor this hard.

Here are the things missing, from the car as it sits right now.

Missing:
Air filter
Exhaust
Fan for interior vents doesn't work (well sometimes, but that is a different story...)


Any help or suggestions would be great!

[lancer360]

There are a couple of things to check with the brake calipers. First question is it a floating or fixed caliper? If it is fixed then it is a piston issue. If it is floating, the caliper itself may be sticking on the slide pins. Most likely you have excess wear in the piston/bore area which is allowing the piston to get jammed. You best bet is to try and purchase a new or re-manufactured caliper. Do them in axle pairs as you could end up with different braking effort left to right with an old and new caliper. With a floating caliper, you also need to make sure that the caliper floats freely on the slide pins. Pull the pins and make sure they are in good condition with no grooves, gouges, etc that could cause it to hang up. Also make sure you clean everything well and use a light, high temp grease to lube the slides. Don't get sloppy with the grease as you don't want it on your rotors. That could ruin your day real quick! If you don't use a high temp grease, the heat will either melt or burn it off.

As far as the car diving back and forth, that could be a couple of things. First thing is it may be your shocks or struts (not sure what the car has) and not the brakes. If the they have more than 100,000 miles or are old then replace them. Bad shocks can have nasty effect on braking because they can't deal with the extra load put on the front of the car during braking. If they are really bad, you may even be getting close to or on the bump stops which will cause uncontrollable handling. Next, I would check the rotors and make sure they aren't warped. You will need a dial gauge or take them to a shop/parts store that can check them for you.

Have you felt any other handling issues? Have you checked all the suspension to make sure everything is tight and there is no play in any of the ball joints?

As far as the radiator spewing water out the top/side, I am guessing it is a radiator that has plastic end caps. These plastic end caps will crack when they get old. Sometimes, the cracks can be invisible to the eye and only show up under pressure. As far as the pressure, start with the basics. Make sure you are running the correct mix of fluid. Contrary to popular belief, anti-freeze is a horrible coolant. It is only there to keep the water from freezing, so make sure you only use the amount you need. You can try adding water wetter which can help improve the cooling ability. Next, check the thermostat. Take it out of the car and drop it in pot of boiling water. You should see it open. However, the things are cheap and if you have gone through the effort to remove it, you might as well throw it in the trash and get a new one. The next thing to check is the radiator. If it is old, odds are it has some build up which is clogging it. Since you have a leaking radiator, it will most likely be cheaper to put in a new one rather than try and get the old one repaired. If you do get the old one repaired, make sure you get it cored to remove any blockage. The last thing to check is the radiator cap. Make sure it is the correct pressure for your car. You can get higher pressure caps which will raise the boiling point, but the higher the pressure, the more stress you put on everything from hoses to your head gasket. A blown head gasket would really ruin your day!

P.S. I wrote this assuming this car is new to you and don't know the mechanical history of the car.

[NCMR2]

Wow, that will give me a few things to play with. You are right, this car is new to me and it's mechanical history up to this point are unknown. What I think would be my best bet, and not a bad anyways would be just to replace the pads, rotors, rear calipers, radiator and thermostat. This is going to be a slow project as money is tight right now. Oh well, that is what project cars are about though right!? haha

[lancer360]

Good luck with the project! I'm in the middle of one too rebuilding a KBS Mark 7 Formula 500.

[NCMR2]

So I noticed something today that i should have noticed before. I have already said that I have an oil leak somewhere that needs to be addressed. In trying to crawl under the car to see where the seepage is coming from, I noticed what looked like oil on the flange connecting the headers and and b-pipe. I looked down the exhaust (empties in the middle of the car) and noticed that everywhere the exhaust smoke had a nice coating of what looked like, well, oil. I am guessing that the motor is not burning the oil, but some how leaking into the headers maybe so the heat from the exhaust is burning it up giving me a nice, thick white smoke. Hopefully tomorrow I will take it to a shop to put it on a lift to figure out what is going on here.

Anybody know what could be the problem?

[wmmpayne]

Brakes: If you have pulsing in the pedal, you've got one or more warped rotors. Cheapest, quickest brake fix: Flush the system, using Castrol LMA (Pep Boys has it), shouldn't take more than 2 quarts to accomplish. Procedure: www.trustmymechanic.com/brake_fluid_change.htm

Antifreeze/Coolant: Ethylene Glycol (green) raises the boiling point of the mixture as well as reduces the freezing point. You always need a 40-50% solution for maximum corrosion protection. Sounds like your radiator is about to bite the dust.

[stealthgtfour]

ah, yes the venerable Hachiroku! start saving for a honda f20c (s2k engine)