QG18DE engine overheating and no heat from vents
 

hey guys! All help will be greatly appreciated. Ok, dec 25th the car suddenly starts overheating and also then out of nowhere there's no heat coming from the vents. Have literally tried everything except the cylinder head.

First i thought it was the thermostat but changed it and it wasnt the thermo. Then i checked all hoses and tried bleeding the system and flushing it with garden hose and there are no obstacles in the cooling circuit. Then i ofcouse thougt it was the waterpump. After a bit of struggle getting the pump out and new in there still isnt any water moving through the engine or the radiator. (only when the car is on) because when off i easily can get water through the entire cooling system. Also have tried making the car heat with no thermostat but still no circuit. Upper hose from radiator is getting hot and the lower one not even warm. At dec 26 i checked the oil and it looked fine but when i checked it again yesterday after all this work the oil is very very very milky. Best to say also when i put the new waterpump in it has a low leakage through the gasket that i will not bother to fix if it need a cylinder had repair. Why can i flow water easily through the entire system but when the car starts the water won't circulate and because of pressure in the system and air buildup the reservoir tank fills and i have bleed the system many many many times.

So basicly my question is: Is this the cylinder head? Or is there anything other than that, that maybe causing the cooling circuit not flowing? and also can cylinder head problems cause problems like this?

thanks guys for all the help! Have read alot here and good site! http://www.nissanforums.com/images/smilies/smile.gif

also could exhaust gas be leaking into the cooling system? and causing water blockage through the cylinder?

Same Problem
 

Hey buddy, I just bought a 2001 Sentra 1.8L with the exact same problem. Can you or anyone tell me how to fix this thing please? It is driving me crazy.
Thanks again

I couldn't give you a definite answer without seeing it, but typically milky oil combined with overheating would indicate a head gasket problem.

No coolant in the oil but air bubbles in the coolant. how can I tell if the waterpump is week or intermitant?

Hmm...Worn fin on the water pump? but then again you did mention it was replaced with a new one. Possible clogged radiator... or...Did you put in the right coolant mixture?

Dear it is all about blown gaskit change it otherwise engine need to be replaced

Heater core?
 

Mine did that to me at the beginning of last fall. Took it to my mechanic, they did a back flush and pulled out stop leak from the dealer trying to get it to stop over heating during the summer.

Hope this helps.

KF