Overheating

[EuroTrash///E30]

I just replaced my entire cooling system, new water pump, radiator, thermostat, fan and fan clutch, hoses and put new belts on it, but it still runs hot when i drive it. It cools down when it idles. I checked the oil for water and it was fine and made sure my belts were tight. Anyone have any suggestions on what it could be?

[Swanny]

Burped the system yet?

[EuroTrash///E30]

Yeah, already did that too

[Swanny]

Mine was just acting a fool the other day....somehow got an air lock somewhere so i ran it with the heat on, and kept playing with having the cap on/off and adding fluid till it stopped accepting any more. Haven't had a problem in over a month now.


So I guess my question is did you have the heater on wheb you burped?

[EuroTrash///E30]

no, the heater was off when i burped it

[stamar]

actually air in the system will usually overheat when idling and go down when at freeway speeds.( if its a small enough bubble)

does the heater blow cold?

[EuroTrash///E30]

No, the heater blows hot

[EuroTrash///E30]

No ideas?

[dnguyen1963]

Bleed your system again with the heater on Max. Take out the tstat and drill a small hole on top to facilitate air removal.

[Cletonius]

Bleed your system again with the heater on Max. Take out the tstat and drill a small hole on top to facilitate air removal.

Don't drill holes. Jack the front up about an inch, helps a lot

[Kvasi]

Park in a steep uphill and let it idle and bleed it, should do the trick. If not do the same and keep it steady at about 2k rpm.

[Swanny]

Yup

[Ceeker]

drilling the hole won't matter either way. it can help with releasing trapped air but won't affect the operating temp of the car. put the car on a slight incline about 20 degrees. run the motor with the heat on full. top up the coolant, get the car hot -crack the bleeder open and as mentioned get the revs up to 2k or so. you will see steam and some gurgling coming out. Run it till you see a stream of coolant coming out. close the bleeder and watch the temp gauge. Then take it for a spin if it is still doing it - repeat the process until temp stabilizes.

question: by chance are you running the a/c while driving? if you aux fan isn't working the temp will increase with the extra load on the engine. that's if you have or use a/c. often the aux fan resistor packs it in and although the a/c works your engine temp will rise.

[stamar]

bleed it from the overflow hose near the radiator cap. dont drill a new hole unless you have a new screw to put in it, what you just did was creat another leak.

[dnguyen1963]

bleed it from the overflow hose near the radiator cap. dont drill a new hole unless you have a new screw to put in it, what you just did was creat another leak.

??? How can a small hole in the tstat create another leak? Trust me, this helps bleeding the system very well. Even parking the car or jacking it up can still have air trapped in the tstat housing. Keep in mind that, in colder climate, small hole in the tstat will require a bit longer for the engine to get up to operational temp.