overheating issue

[Pblesh85]

My water temp is rising and i dont know why. I have a 93 coupe with a blacktop and some go gast stuff(about 240-250ish whp on an untuned ecu @7psi)

the car has as follows

S13 SR20det blacktop
Tub manifold with Metal gasket
GT2560R-466541-4 (GT28R) Dual Ball Bearing Turbo w/Internal WG
Alum adap's for the turbo
S15 oil return
Earls oil and coolant lines (with restritor)
upgraded exhaust elbo
3" down pipe
3" test cat
3" exhaust
oil catch can
new water pump
New gaskets
30x12x3 FMIC
HKS SSBOV (New Style)
WAL 255 fuel pump
Battery relocated to trunk
New Radiator with dual Mishimoto Fans
DIF fan contoller
Alum coolant tank
Brake Heat sheild...
All new hoses and Belts (gates)
Mobile 1 synthetic

Im not leaking coolant(anymore, loose radiator dran plug) my fans work fine and its not too hot out here. It does it in stop n go mostly.


If anyone has a clue please let me know. My radiator is is a new oem ka radiator. Is this possibly an issue ? A koyo is about 2-3 weeks away.

Thank you, desperate and confused.:eek3:

[wangan_cruiser]

check the water temp sensor could be bad.

[my S14]

thermostat issue thats what i would try first, if your thermostat is stuck open or sticky it would over heat at idle and stop and go. theres no real airflow and if its open the coolant it just circulating around and the fans are not doing their job, when your driving the air flow from the road helps cool everything down.
thermostats are quick easy and cheep. thats what i would start with for sure.
then again im not an srdet guy thats just my best guess

[Pblesh85]

I will check it this weekend and give an update, thanks.

[Pblesh85]

Ok so I changed my thermostat(brandnew nismo) and after 2-3 min at idle my temp gauge is through the roof. Im not leaking anything, my fans work just fine. Then hoping its just waiting for coolant to cycle through the motor and go back to normal. I wait 2 hours and drive down the road nice and easy no stop n go and 2-3 min its through the roof again. Before I changed it my car would run for 30-40 min before the temp went up(slowly). Now it goes up alot faster. And when I pop the hood it does not feel extra hot or out of the norm.

What the hell is going on ? Anyone that has an idea please tell me. I dont think it the coolant sensor because it read stable for 30-40 min before it would start to go up. Has anyone delt with this before ?

[Pblesh85]

Will an sr run fine with a new ka radiator ?

[Jadeskyline]

i had a similar issue....tiny pinholes in my heater hoses u wont see them but they are there

[Pblesh85]

So did you have fluid leaking ? How did you fix your prob ?

[SR2Zero]

Okay, various suggestions that may or may not help.... Just kinda thinking out loud..

Insufficient water pump possibly... Sucky coolant circulation..

Empty, flush, fill, bleed radiator.

Make sure there is no air is in the coolant system.... Err... Radiator cap is good to go...

All I got.

[Jadeskyline]

no fluid leaking i sat in front of the car for 30 min and saw nothing went driving car heated up heard a loud hissing noise (because i kept driving stuck in rush hour traffic)....finally pulled over and popped my hood and heard that the hissing was coming from a few TINY (and i mean TINY) pinholes....i just switched out my heater hoses and called it a day....does ur car overheat at idle as well or just while driving?

[Pblesh85]

Its a brandnew water pump(less than 1000 miles), it overheats at idle too.

[Sileighty_85]

i found an effective way to bleed my system

1. fill radiator full
2. turn on/open heater
3. go WOT (2nd gear) till 6K let off gas and let the engine brake
do that 2 or three times and that should purge you system of air.
4. check coolant level and refill

Ive done this everytime and has worked for me with out a problem.

No insult intended but gotta ask

are your fans pushing or pulling the air in the correct direction?

[Pblesh85]

yes my cooling system is set up correctly. I might still have air in there. Im going to try bleeding my system again.

[NISMO WARRIOR]

I had the same problem on my Black top got it fixed wen i found out that the heater hoses wen u run a heater core wasnt tight enough...... I know little things turn into big ones.

[scooz14]

test your radiator cap to make sure it holds pressure. if it does not, it will overheat.

[Pblesh85]

I will check it out. Does an sr need a cap that holds more pressure than a ka ?

[hwd_ca]

Just take out your Thermistat...That might work.

[Pblesh85]

I solved the problem for the most part. I had to bleed the cooling system. As soon as I can buy a new radiator I believe the problem will be compltely solved. Although I now have a new prob. The bleeder screw/bolt behind the crank angle sensor on the water neck it stripped. I believe is the water neck thats stripped and not the bolt.

Does anyone have an extra they can part with ?

[GSXRJJordan]

you almost definitely have air in the system. There's a bleeder screw on the water neck, take it out, start the car, turn on the heater, and keep the radiator full of coolant while coolant gets pushed out of the bleeder. You'll see a bunch of bubbles at first, then it'll be a solid stream.

Then put the screw back in, but be careful, that coolant will be hot.

Edit: buy the S14 water neck from a Nissan dealer, or find a used S13 one for next to nothing.

[Pblesh85]

Do you have a part # for the s14 one ? And thats what I did to bleed the system.

[WISH ONE]

sometimes it helps to jack the front of the car up so the radiator is at the highest point, you can squeeze the upper hose in a pumping sort of manner, dont burn yourself and like every one else has said turn the heater to the highest setting possible.this helps.....http://i20.photobucket.com/albums/b243/mikeishellafresh/coolantfunnel.jpg

[Oo_Skyline_oO]

I've never worked on SR, but I kno on KA's there are coolant bypass hoses under and in between the intake manifold. check if they leak, and are the fins bent on the radiator??? if you have electric fans, make sure they are pushing air in the direction of the motor, and if you have clutch fan, make sure that the fan clutch isnt too loose, or it will heat up on idle.

[Sileighty_85]

Do you have a part # for the s14 one ? And thats what I did to bleed the system.

http://www.thenismoshop.com/ikorb.php?func=catalog&category_id=3310&product_id=354

[mifesto]

also try adding a bottle of waterwetter.... it helps break up the bubbles...

[WISH ONE]

does you heater work well?????

[Pblesh85]

Thanks for the help and the website. All of this should be completely solved as soon as my koyo and water outlet gets here.