random overheating
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GotdaDrift
- Posts: 20
- Joined: Wed Nov 23, 2005 12:52 pm
- Car: 1989 240sx (180sx)
random overheating
I just swaped a dualcam ka into my 89 and it has been running perfect but then out of no where its starting to overheat but not all the time it will just pin the needle in a matter of sec, then drop back down after a little or if i turn off the car it will drop no problem. i have put a water pump,thermostat,new rad cap. i dont know what to do. also when the temp goes up it goes into the overflow but the collant isnt even hot. its very starange. if anyone knows what i can do please let me know.Thanks
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DjPantsSpecR
- Posts: 1711
- Joined: Fri Jan 14, 2005 12:49 pm
- Car: 93 Nissan MS13
92 Nissan RMS13
i gotta disagree.
air bubbles in the coolant cause the temp to raise dramatically then drop quickly. Thats why coolant is being displaced as well. thats also why the coolant in ther overflow isnt hot. the air is the only thing thats overheting as it has a much lower specific heat constant, causing it to expand dramatically way before the coolant.
So, you just did this swap right? how long ago, and how much driving have you done without it overheating. how long are these trips as well.
now search around, because there are a billion threads on how to burp the coolant system, but my favorite is to get a burp funnel, turn the heat all they way to hot, and then run the car. this is the shortened version, but you'll find the real deal through searching.
on the other hand, if youve been driving it for a while, its a blown head gasket....
air bubbles in the coolant cause the temp to raise dramatically then drop quickly. Thats why coolant is being displaced as well. thats also why the coolant in ther overflow isnt hot. the air is the only thing thats overheting as it has a much lower specific heat constant, causing it to expand dramatically way before the coolant.
So, you just did this swap right? how long ago, and how much driving have you done without it overheating. how long are these trips as well.
now search around, because there are a billion threads on how to burp the coolant system, but my favorite is to get a burp funnel, turn the heat all they way to hot, and then run the car. this is the shortened version, but you'll find the real deal through searching.
on the other hand, if youve been driving it for a while, its a blown head gasket....