engine keep on overheating, need help.

[Just another 240]

wsupz all

i have a 91 240sx, i recently changed the water pump, theromstate and added new coolant. My heat and engine was runing pERFECT, until my friend gave me a new radiator cap to put on. After i put it on, drove home and notice my temp gauge needle was all the way up to the red line. So i bleed it, seems ok, drove it again and it goes to the red line again. It only do that when my car is stopped.

So i bleed it again, ALOT and i mean ALOT of steam was coming out of the bleeding hole, it wouldn't stop. My temp needle pass the red line so i got scared and shut off the car. Can someone tell me what's wrong?

[fiznat]

uhmmmm try putting your old cap back on and seeing if thats the problem!

...also maybe you (or whoever) didnt install one of those things right?

[Just another 240]

i alredy threw again the old cap, i told my friend to look around it for me cause is right across the street from his house. He said he didn't find it.

well i installed everything, and my cooling system was working PERFECT, no over heating, HOT *** heat. It only start over heating after the new cap is put on.

i was thinking maybe the new cap is defective, so i took my friend's cap from his car. And is still doing the same!

[fiznat]

heh well... I donno what it is if everything is perfect as you say. (although just having the heat work isnt an indication that your thermometer is working) But I suggest whenever you drive your car (if you do at all), to run the heat at full blast to help cool the engine.

[Just another 240]

that's it?! damn i need a answer to solve the problem...lolz

but thaknz anywayz..haha

[Repo Man]

You're sure both caps sealed well? Were they the proper rating? It's possible you got a defective water pump and there is no real correlation between the cap and the appearance of the problem. You have enough coolant in the system I assume.

Go back and recheck everything. I'm also moving this to the online mechanic section for you.

[Just another 240]

yes, the cap from the resevor, the cap on the radiator is sealed tight. For the rating, the old cap didn't say how many psi, it said 0.9 or .09 either one in kg, and my friend got the same exact # in kg. which it turns to be 14psi. Coolant level was also good too.

[Just another 240]

ok i just went all the way back to pick up my old cap and luckly found it( it had been 2 days). I put it on ..fill up the rad and resevor, with coolant, bleed it, blahc-blahc-blahc. and it still doing the same thING!!! o my god this is driving me nut.

[yellow_jacket]

Pull the thermostat again and either leave it out or replace it. If that doesn't take care of it, you can try the water pump, but it is kind of unlikely. Was the car overheating before you changed the pump and stuff? Does the car only do this while stopped? while driving? Any smoke coming out of your tailpipe? Need more info. But start by removing or replacing the thermostat. You may have just gotten a defective one.

[Just another 240]

it does not overheat before i change the waterpump and thermostate. not even after, only after i replaced the cap which is like a week after the pump and thermostate change. It only happen when i come to a stop, it's perfectly fine while i'm moving. Tailpipe also have white smoke coming out, but not alo,t also i notice water at the tailpipe too. Yeah i was thinking pulling out the thermostate again and buy a new one and see what happens. The part i hate is not even the trouble pulling out the theromstat, is the money i need to spend buying coolant over and over again. This is like my 5th time going to buy coolant. When ya change coolant or watever, do ya bleed the system?

[Just another 240]

would a blown or leaking head gasket make my car overheat? it'll suck up my coolant slowly but what about over heat?

[Just another 240]

hello people?help help please

[rschwalbe]

The last time I had this happen to me there was a little hole in the radiator that leaked out a lot of the water and a bad thermostat. It is not hard to believe that the new one you put in is either upside down or just bad. That is where I would go first if you do not see any leaks.

[yellow_jacket]

Yes, a bad head gasket will cause the car to overheat and blow white smoke and of course use coolant. But if this only happens while you are sitting, it sounds more like a fan problem. By the way, if the head gasket is blown, it will be a kind of sweet smelling white smoke.

[Just another 240]

aite ppl, i dotn' know what's up with my car, but i'm bringing it up to my school tommorrow(friday) so the instructors can help me. ( i go to an automotive trade school) i checked on the computer that the cap rating uses 13psi, and the cap i gotten from my friend was 14 psi, don't know if 1psi matter but just want to point this out to people who want to know what psi uses on a 91 240sx. Thanks guys

damn my head gasket have to be change soon, hopefully it'll last me till the summer, becuase is toooo cold to do it now.

[Just another 240]

ok people( for people who cares and want an update or something)

bought my car to the school, the instructor and i spend the whole morning and afternoon fixing it. We changed the thermostat and cap again x2. Well, my heat came back, that's 1 thing. When we were at the school we rev the engine bleeding it and stuff, it stayed normal (thought it was fixed). But once i take it out on the street and drive, when i hit a red light the temp needle goes back up again. So right now we have no clue what's wrong, so i gotta do a pressure check on it. It might have a leak somewhere cause becuase air bubble never stop coming out from the bleeder hole.