The car: 95 240sx w/ s13 headThe problem: I had to do a head swap due to head warping while overheating and ive replaced every possible cooling part on my car. I have bought a water pump, radiator, nismo thermostat (already tested and it works great), new plugs, radiator cap, and about 7 million gallons of collant. I replaced the head gasket with a head up felpro kit and all intake and exaust gaskets as well.
The weird thing is ive ran a compression test and came up with 210 210 210 210. I had the cylinderhead milled due to warpage and had new valve stem seals installed. The system runs great but as soon as i drive for 2-3 min. while warmed up, the ac fan kicks on and the system over heats. Thinking that it was my heater core malfunctioning, i bypassed that as well. I've completly flushed and bled the system.
Even after all this, no avail. I have 0 idea and have searched for ever possible out. Nothing is actually working.
Need help with overheating
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nismo dreaming
- Posts: 248
- Joined: Tue Nov 22, 2005 3:31 pm
- Car: 1996 240sx LS1
Re: Need help with overheating (jaytheman88)
is your ecu throwing any codes? It's possible that your CTS is malfuctioning and giving off false readings. Is your clutch fan kicking on?
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nismo dreaming
- Posts: 248
- Joined: Tue Nov 22, 2005 3:31 pm
- Car: 1996 240sx LS1
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nismo dreaming
- Posts: 248
- Joined: Tue Nov 22, 2005 3:31 pm
- Car: 1996 240sx LS1
Re: (jaytheman88)
bump....please help, its my only car
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nismo dreaming
- Posts: 248
- Joined: Tue Nov 22, 2005 3:31 pm
- Car: 1996 240sx LS1
Re: (180fan)
The ac fan kicks on at 202 degrees f. Unforunitly, this doesnt help.
Re: (jaytheman88)
There is still probably air in the coolant system. Your best bet may be to drain down the coolant and start all over again with the filling of the coolant.
Here's how I do it:1 - drain coolant2 - open the bleeder screw3 - optionally jacking up front of car helps to purge air pockets4 - fill system until coolant starts coming out the bleeder hole5 - close bleeder screw (not too tight; screw is easy to break off)6 - continue filling until coolant is at the bottom of the filler neck7 - do not put cap on the radiator8 - start motor; as coolant starts to warm up, you may see a few air bubbles9 - squeeze the hoses by hand to free up possible air pockets10 - put cap on radiator
Here's how I do it:1 - drain coolant2 - open the bleeder screw3 - optionally jacking up front of car helps to purge air pockets4 - fill system until coolant starts coming out the bleeder hole5 - close bleeder screw (not too tight; screw is easy to break off)6 - continue filling until coolant is at the bottom of the filler neck7 - do not put cap on the radiator8 - start motor; as coolant starts to warm up, you may see a few air bubbles9 - squeeze the hoses by hand to free up possible air pockets10 - put cap on radiator
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Eikon
- Posts: 6928
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- Car: 71 240z, 93 Supra TT
- Location: Lake Orion, MI
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Re: (rogoman)
Are you positive you are getting coolant flow through the system?
When it warms up, do both upper and lower radiator hoses get hot?
If both hoses get hot, that would prove that you have flow through the radiator and that your water pump and thermostat are working properly.
If you've replaced all the cooling system parts and you're sure they work... then you must have some restriction of flow through the engine... that would be either an air pocket, or an actual blockage. I've heard of people getting bits of rag or cloth stuck in the coolant passages...
You might try pressure testing the coolant system as well...
Another idea.... Try yanking the thermostat out and run with no thermostat for a bit. It won't hurt your engine to do it... that might tell you something...
Being in Texas sure doesn't help does it... We better get this figured out before it really get's hot outside.
Let me know if both hoses get hot... and try taking out the thermostat entirely... see if that helps... Sometimes those things get installed incorrectly and even though they test out... they still can cause problems.
When it warms up, do both upper and lower radiator hoses get hot?
If both hoses get hot, that would prove that you have flow through the radiator and that your water pump and thermostat are working properly.
If you've replaced all the cooling system parts and you're sure they work... then you must have some restriction of flow through the engine... that would be either an air pocket, or an actual blockage. I've heard of people getting bits of rag or cloth stuck in the coolant passages...
You might try pressure testing the coolant system as well...
Another idea.... Try yanking the thermostat out and run with no thermostat for a bit. It won't hurt your engine to do it... that might tell you something...
Being in Texas sure doesn't help does it... We better get this figured out before it really get's hot outside.
Let me know if both hoses get hot... and try taking out the thermostat entirely... see if that helps... Sometimes those things get installed incorrectly and even though they test out... they still can cause problems.
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nismo dreaming
- Posts: 248
- Joined: Tue Nov 22, 2005 3:31 pm
- Car: 1996 240sx LS1
Re: (Eikon)
First off, thank you for giving me some advise!! And yes, its very hot down here.
To answer your question, we did take out the thermostat and it ran ok for about 3 cold days. On the first hot day...it overheated. The bottom hose on my friends s13 gets to the same temp that mine is ( used his as a an example ) so that kind of rules that out. After it overheated, we did exacually step by step why you said above to get out the air bubbles.
One small note, whenever i add the radiator fluid, a see soem kind of black swirl coming up. Im not sure if thats the rad fluid mixing or what, but it looks wierd. Also, i never replaced the temp sensor (never knew to until today. ) Could that really make it over heat though?? Doesnt really seem like it could physically do that.
On the way to school this morning ( i only live like 2 miles away ) it started to get hot. As i stopped to let it cool down, i called my folks to tell them what happened and the kind of forced me to take the durn thing to a shop. I hope they can find this issue but i would really appritiate more advice and tips as to solve this problem.
Modified by jaytheman88 at 5:56 PM 4/10/2006
To answer your question, we did take out the thermostat and it ran ok for about 3 cold days. On the first hot day...it overheated. The bottom hose on my friends s13 gets to the same temp that mine is ( used his as a an example ) so that kind of rules that out. After it overheated, we did exacually step by step why you said above to get out the air bubbles.
One small note, whenever i add the radiator fluid, a see soem kind of black swirl coming up. Im not sure if thats the rad fluid mixing or what, but it looks wierd. Also, i never replaced the temp sensor (never knew to until today. ) Could that really make it over heat though?? Doesnt really seem like it could physically do that.
On the way to school this morning ( i only live like 2 miles away ) it started to get hot. As i stopped to let it cool down, i called my folks to tell them what happened and the kind of forced me to take the durn thing to a shop. I hope they can find this issue but i would really appritiate more advice and tips as to solve this problem.
Modified by jaytheman88 at 5:56 PM 4/10/2006
Black swirl? You mean like motor oil? Even with a shop doing the coolant change, I've seen many board members get shafted with air bubbles. I had a lengthy write up a while ago. Maybe I should try to dig it back up since summer's coming back around and it looks like alot of board members are overheating again.