Overheating issue, not sure what it is.
so im having the same issue. i have a S13 Blacktop SR20 w/ T25 turbo with a greddy VSPL fmic, with a koyo rad, dual 14''/12'' electric fans, nismo thermostat and nismo rad cap. dme cooling panel. when im crusing around 65 to 75 on the free way the temp will start to rise up (little boost as possible) fans are running the correct way saw a post earlier about the fans. no bubbles in the lines just put the Nismo Therm. in and the Nismo Radiator cap on when I was changing out the water hoses that run under the intake manifold due to bad leak. Everyday I check the radiator fluid level and its full so I know it flows with the overflow but I can't find out why it overheats when I'm just cruising. There is no oil bubbles floating. And I'm not running the A/C either, I tried to run the A/C one time to see if the overheating issue was cured but no sir. So I tried without and no again. I don't have Water wetter yet because I'm going to replace my stock overflow with the Aluminum overflow.
Re: (SRspoolin)
What were your numbers mine were 155 155 140 and 120.SRspoolin wrote:
this is what mine is doin so i did a compression test and came out fine?
Sr_Silvia did you properly bleed the system? As in starting the car using the air relief valve, to get some air out then turning the heater on full with the radiator cap off?
Some also have their front end jacked up all the way or on a slanted driveway to help get all of the bubbles out. Mine still overheats if i don't have the heater on, I just contribute that to my stock ka radiator and the front mount right in front of the bastard.
Some also have their front end jacked up all the way or on a slanted driveway to help get all of the bubbles out. Mine still overheats if i don't have the heater on, I just contribute that to my stock ka radiator and the front mount right in front of the bastard.
Re: (Morph)
No I haven't tried the bleeder valve. I will do that and see what happens. Should I let the car warm up and then bleed or does it matter if its cold. I never knew about the heater on and radiator cap off thing.
But when the car does overheat I always do turn the heater on to cool it back down when I'm driving.
But when the car does overheat I always do turn the heater on to cool it back down when I'm driving.
Re: (SR_Silvia)
I think the fsm covers bleeding but just incase, when the car is cool unscrew the bleed valve and start the car and put the heater on full. Coolant is going to be pouring out while the screw is out so be aware to have something to catch it. Once fluid starts to come out and no air bubbles replace the screw. After replacing the screw and the car is at normal operating temp, with the heater on full blast vent the pressure from the radaitor and remove the cap. The fluid level should go down as it stats to circulate through the engine. Add flud till it doesnt drop any more. That should get the bubbles out of the system.
If i mistated something or missed somethine someone please correct me.
If i mistated something or missed somethine someone please correct me.
Re: (Morph)
Ok so I tried what you said and was sitting there for about 40 minutes worth of small bubbles and few large air bubbles coming out. But hopefully this helps if not then I don't know. Maybe water pump next I guess.
OP, have you replaced your radiator cap?
My car's been trying to overheat off and on for the past two or so weeks, even after replacing the thermostat. Yesterday it was pretty bad and I heard a bubbling sound from behind the motor when I shut it down.
I noticed this morning when the engine was cold that I could squeeze the upper radiator hose and hear coolant rushing to the overflow tank. I realized it was still the original KA radiator cap and sure enough the lower seal had deteriorated a bit and formed a crack.
I did a little searching on the internet and learned that the coolant system needs to stay pressurized because it dramatically raises the boiling point of the coolant. I also learned that KA and SR radiator caps are different. KA caps have a 12.6psi spring and SR caps have a 16psi spring. I bought a cap for a '91 300ZX which is also rated at 16psi and so far it seems that my problem is remedied.
I don't know why coolant wasn't being forced into my overflow tank with the bad radiator cap.. It was holding a good amount of pressure, enough to firmly balloon the radiator hoses when it got hot.. but it would seem that it was leaking just enough pressure to lower the boiling threshold.
If you're still using your original KA radiator cap, I'd suggest ponying up the $10 and getting one for a 300ZX at Napa. Even if it doesn't help with your problem it's a cheap way to know it's one thing that the problem is not.
My car's been trying to overheat off and on for the past two or so weeks, even after replacing the thermostat. Yesterday it was pretty bad and I heard a bubbling sound from behind the motor when I shut it down.
I noticed this morning when the engine was cold that I could squeeze the upper radiator hose and hear coolant rushing to the overflow tank. I realized it was still the original KA radiator cap and sure enough the lower seal had deteriorated a bit and formed a crack.
I did a little searching on the internet and learned that the coolant system needs to stay pressurized because it dramatically raises the boiling point of the coolant. I also learned that KA and SR radiator caps are different. KA caps have a 12.6psi spring and SR caps have a 16psi spring. I bought a cap for a '91 300ZX which is also rated at 16psi and so far it seems that my problem is remedied.
I don't know why coolant wasn't being forced into my overflow tank with the bad radiator cap.. It was holding a good amount of pressure, enough to firmly balloon the radiator hoses when it got hot.. but it would seem that it was leaking just enough pressure to lower the boiling threshold.
If you're still using your original KA radiator cap, I'd suggest ponying up the $10 and getting one for a 300ZX at Napa. Even if it doesn't help with your problem it's a cheap way to know it's one thing that the problem is not.