coolant problem

[giarc]

I have a problem with a 1988 dodge lancer.I have replaced the thermostat and the cooling sensor recently,and also the rad.The temp gauge in the dash is showing normal temp range.The coolant seems to boil from the engine into the reserve tank and will not return.It seems that the engine gets too hot before the cooling fan comes on.This is a 2.5 engine.There also seem to be air in the system,which i cannot get out.THANKS FOR ANY ADVICE.

[pcv]

I think you may have a bad head gasket.
Remove the spark plugs and look at them. Are they whitish? If so, that cylinder has coolant leaking into it. With the plugs off, pressure test the cooling system and and after a while look inside the cylinders for coolant or crank the engine ( stay away from the plug openings, unless you want to have a shower) and watch for coolant spray.
What is happening in your case is the compression from the cylinder is leaking into the cooling system and blowing it into the resorvoir.

[theslicksteve]

Originally Posted by giarc

I have a problem with a 1988 dodge lancer.I have replaced the thermostat and the cooling sensor recently,and also the rad.The temp gauge in the dash is showing normal temp range.The coolant seems to boil from the engine into the reserve tank and will not return.It seems that the engine gets too hot before the cooling fan comes on.This is a 2.5 engine.There also seem to be air in the system,which i cannot get out.THANKS FOR ANY ADVICE.

i agree it is almost definetly your head gasket. but is pretty easy to change. chrysler 2.2 and 2.5 are known for eating head gaskets

[Bazilisck311]

usually if you have a blown head gasket, and coolent is leaking into the cylinders, the car should be blowing out white smoke from the muffler.

[Polygon]

Originally Posted by Bazilisck311

usually if you have a blown head gasket, and coolent is leaking into the cylinders, the car should be blowing out white smoke from the muffler.

Not always, it would have to be a fair amount for that to happen. I agree that it sounds like a blown head gasket.

[Bazilisck311]

and im guessing if you let it slip that far, expect some piston warping and all that?

[Polygon]

Originally Posted by Bazilisck311

and im guessing if you let it slip that far, expect some piston warping and all that?

Not really, but if you have that much coolant leaking in then you probably have a cracked block or head.

[Bazilisck311]

lol, well that happend to me. blown head gasket, white smoke everywere, i didnt crack the block but the bearings were all f'ed up

[proticus]

if your head gasket checks out ok, start by replacing your radiator cap, it could prevent the fluid from coming back in from the reservoir. as far as the air being in the system, start the car and let it warm up with the radiator cap off, and fill it up with fluid. make sure that it warms up good, so that it starts to pump the fluid through the engine, so you can get the air out of there too. if this doesn't work. check your thermostat housing. in some dodge/chryslers the thermostat is the highest point in the cooling system, so this is where the air builds up. if this is the case, then there will be a nipple on the housing to let you bleed the air. to bleed it, let the car heat up like normal, w/ the radiator cap on, and loosen the nipple until it starts spewing air/mist/fluid. let it squirt lightly for 5 seconds, then shut it and wait 30 seconds, and repeat. do this several times, until you get nothing but fluid coming out of the nipple