Is there a bleeder valve or screw for a 2001 gmc jimmy coolant system?

The procedure for bleeding the brakes on your jimmy should be the same as any car or truck. If you have to raise the vehicle to access the bleeder screws, make sure you use jack stands and have it properly supported. The bleeder screws are always at the top of the brake cylinder or caliper on the inside of the four wheels. Start with the wheel that needed repair or the one that is the farthest from the master cylinder. Loosen the bleeder screw and have some depress the brake peddle and stop no more than 1/2 of the way down (master cylinders do not use much of their capacity so often there is roughness in the bore at the deeper areas). When the peddle is 1/2 way down, close the screw and then have your assistant release. Repeat this process until you have a good flow of fluid with no air. Keep bleeding the next farthest wheel until you have done the effected part of the system (front or rear, or all four). Pump the brakes (1/2 way) until you have a firm peddle and let it set for a few moments. You should have a firm peddle, if not repeat the process. I prefer to purchase a automatic bleeder screw which is like a check valve from a parts store. It is installed temporarily and allows for a one person operation.

To fix a vapor lock just let your car cool down, take off your radiator cap to the first notch, not all the way, and start the car and let it idle until some coolant starts to come out. Then turn off the car and put cap back on, being careful sine the coolant will be hot. On some models there is a bleeder screw, usually on or near the thermostat housing. It is a brass screw, so be very gentle with it as it will easily break if over tightened. Unscrww the bleeder until solid liquid with no air comes out and then tighten gently.

Those valves sound like fuel pressure test ports. Press down the center of valve and see if gas comes out. If it does, those valves are on the fuel rail, not in the coolant system.
A bleed valve is a bit different. Looks kind of like a grease zerk, with a small hole on its little round head. You put a small wrench on the valve and turn it as if loosening it, but only a turn or two to open it and let coolant or air out the hole on the valve. Look for it on or just close to the thermostat housing.
If you have no bleed valve, best practice is to fill radiator and overflow tank, then start car with the radiator cap off, and let engine run until the thermostat opens (upper radiator hose will get hot when thermostat opens). Now turn off engine and replace radiator cap. This usually gets all the air from coolant system, but sometimes you have to do it again.

The same thing happene to me. i just replaced bleeder valve with a bolt. Take your old bleeder valve to hardware or auto parts store to see which type of threading you should get first. Goodluck.

on the slave cylinder on the front side of the transmission.

Try the free online service manuals at:

http://www.autozone.com/autozone/repairinfo/repairInfoLanding.jsp

Sign-up for access, just takes a second and an email address.

air pockets possibly or your fan is not kicking on. look for a bleeder valve for the coolant and bleed the system when its running, or leave the radiator cap off and let it run for a while then top off system.

You have air in the system, you will need to work that out, some engine have cooling systen bleeders, if not loosen a heater hose to bleed air from the system.

did you open the bleeder valve and colaspe the piston all the way in? did you clean the rail slider so that it will move freely and not bind up withthe rubber boot? I use a C clamp to compress the piston all the way in.

back by the exhaust up around the case verry hard to get to good luck jimmy rate as fixya