Overheating problem!!! NEED HELP ASAP its my DD

[gt28rsftw]

so i have a sr20det red top in my s13. i have a yashio factory copper radiator only a few months old in it and a new balanced thermostat that i put in on the 14th. and a new radiator cap. my problem is that when the car is at idle it warms up and stays at opp temp fine. once i start to drive the car (rpm's go up or a load is on the engine) it gets above the normal spot on the gauge and starts to try and overheat so i have to stop and idle for like 15min and it goes back down. today i figured maybe there is air in the system. i warmed up the car with the rad cap off and it stayed full. i touched the upper rad hose and it was hot like it should be and i went and touched the thermostat housing and it was piss warm if that. so i grabbed the lower rad hose and it wasnt hot at all maybe warm. im guessing the thermostat isnt getting hot at all like it should be and not opening. i was driving the car for about a month or 2 after i did the swap then had to rebuild the motor. and its been over a month since i had gotten it back together and running and up untill last week it was doing fine. Does anyone have any ideas on what i should do. also i ran it without a tstat one day and it never once warmed up unless i was sitting still then i would get heat. WTF could this be. Im so lost and have done everything i could think of. any help would be great right about now.

[allenms240]

Did you put the thermostat in wrong? Jack the car up in the front, and let the car run without a radiator cap on for ten minutes to ensure no air is in the system. When filling up the rad, take the bleeder bolt out (I'm not sure if sr have one or not). Then replace when you are done filling it up. How is the water pump?
My two cents, buy a new tstat from autozone and see if it works. If it does, then your nismo tstat doesnt work. They are cheap from autozone anyway. Use is as a diagnostic tool.

[breadbox]

on my daily with a KAe my gauge would spike sometime while at a light. My friend noticed the spade clip on the intake that the gauge goes to had a crappy looking wire and after messing with it, the spade clip broke off. I put a new one on and now my gauge doesn't spike anymore.

The other thing is that I want to get a stat that opens at a slightly lower temperature because without running emissions my motor runs a little warmer.

[Lobo240sx]

Could be water pump buddy. Let the car warm up 15 min with the heater on and see if the fluid is moving in the radiator. Yes the SR has a bleeder screw.

[mikes13jonz]

yup maybe in need of new water pump.

did you test the tstat before you put it in to see if it works? put it in a pot of water and heat it up till it opens... oem Tstat opens at 76*c and nismo Tstat opens at 62*c.

when warming up ur car turn heater to high with rad cap off till its running temperature. rev it a couple times and you'll see air bubbles come out and some fluid will overflow but its alright. have a rad funnel so it dosent completely spill out and some rags handy. do this till you cant see anymore air bubbles and your set.

[gt28rsftw]

thanks for the ideas. i have a new tsat in it from autozone the second one i put in. i used a Mr. Gasket balanced thermostat for 160*F its the same size as a factory one but it says gm/ford/amc. when i had the tstat out i could see it flowing just fine. i ran it with the rad open and opened the bleeder till nothing but coolant came out. air came out and it was deff warmed up and i had the heat on blast in the car. thought it was doing good then took it down the road the gauge started to spike and i stopped and could hold the lower rad hose cause coolant wasnt flowing meaning the stat wasnt opening. the tstat housing was piss warm not even close to opening temp. i drive it 15min to work and i can make it there without overheating but im going soooooooo slow and stopping alot to let it stay cool and it still doesnt open. tonight im gonna change out my tstat again and try something else ill find out tomorrow if it works. gotta wait for the gasket to dry before i drive the car. the only thing left to change after this would be the water pump but it seems fine.

[nismoracingsx]

Does your car overheat w/o a tstat?
I just run no tstat and my coupe runs great :p been doing it for years.

[hartig]

does your radiator stay filled? mine has been overheating, and i noticed that one of the heater core hoses was leaking = letting air into the system and screwing everything up. it was a slow leak too..
and do you have a clutch fan or an e-fan? if neither, you should get one or the other..

[OutToWinPAHC]

Chances are its something you did. Either a small leak, or not bled properly. Hopefully you havent warped the head yet.

[gt28rsftw]

well i ran it without a tstat and it stayed cold as hell when i was driving but would get up to opp temp if i was sitting around. i made sure everything was bleed properly its just a mess of a problem, so i figured instead of overheating i would rateher it tun cold. i took out the tstat and it had 2 tabs on it that i bent over after i opened the stat in hot water so it was open but not 100% i figure once it warms up it will it will open it more since coolant will flow past it. and i have a electric fan. i broke my t stat housing so now i have a stupid short one from a 93 SER sentra. i broke the other one when i was putting in the tstat it came out of its lil ridge that it sits in and the bottom bolt area broke off the water outlet. it runs good but since its a bad a** radiator it slowly cools down the car when im cruising. i need to block off like half the rad like a school buss so it stays warm lol. i would rather run cold then hot.... thanks for all your input and help i tried everything.

[OutToWinPAHC]

Running no t stat is also bad for you motor. Check compression, testing cooling system, use a good new tstat, use a oem radiator cap.

[Lobo240sx]

does your radiator stay filled? mine has been overheating, and i noticed that one of the heater core hoses was leaking = letting air into the system and screwing everything up. it was a slow leak too..
and do you have a clutch fan or an e-fan? if neither, you should get one or the other..

^ I remember my 1st SR swap it would randomly do that at the heater core hoses. God those things are a PITA!! I used some Gray silicone around those hoses and it finally stopped.

[gt28rsftw]

car is running prime now, running good temp all the time now after its warmed up but since its 15* out and my rad is baller as hell it starts to cool down a lil bit but not to bad im just driving to work. today it was working prime then my alternator took a s*** so thats my new problem

[HotCarl]

Does it matter what KA thermostat you buy locally....
Thanks

[biggie]

Does it matter what KA thermostat you buy locally....
Thanks

Go to the dealership, OEM is best, problems have occured with ones from local autoparts stores.

[HotCarl]

I have a blacktop S13 sr20det...I was curious if it matters which model ka thermostat you use? Thanks.

[biggie]

I have a blacktop S13 sr20det...I was curious if it matters which model ka thermostat you use? Thanks.

Thermo for all KAs should be the same.

[HotCarl]

thank you sir

[allenms240]

does your radiator stay filled? mine has been overheating, and i noticed that one of the heater core hoses was leaking = letting air into the system and screwing everything up. it was a slow leak too..
and do you have a clutch fan or an e-fan? if neither, you should get one or the other..

^ I remember my 1st SR swap it would randomly do that at the heater core hoses. God those things are a PITA!! I used some Gray silicone around those hoses and it finally stopped.

The heater hose in the bay right at the firewall?
Becuase mine will be fine after I bleed it, and a week or so later it will start to overheat again until i bleed it again, and the process begins all over again.

[gt28rsftw]

your prolly having a pinhole in the heatercore is your floor on the pass side wet at all or is it leaking anywhere else when u park the car? i heard of a bunch of people having this problem since i had it with my car, came to the conclusion drill a bigger hole in the tstat so air can get out and the fluid will flow thru better than when it heats up it will open like normal. i drilled a s*** ton of holes in mine just because i was gettin pissed and will fix it later maybe lol doing great so far though never gets hot anymore unless im stuck in the snow and the intercooler is frozen over blocking all the air from going thru lol. drill a extra hole for the coolant to flow thru and u will be set

[HotCarl]

Ok so I've just about had it over something that should be so cut and dry...I picked up a KA thermostat today. Bought hi temp rtv. So I went ahead and pulled lower hose off, removed the three bolts, pop off the hard pipe and woohoo no thermostat is in the car. So I go ahead clean everything up pop in the new thermostat. Run a bead of rtv along the hard pipe and bolt it on. I go this afternoon to hook the lower soft pipe on and fill it up with coolant. oh f'n great coolant is running from the bottom of the hardpipe right behind the lower bolt. So I pull everything out and clean it all up again and second attempt. So I get everything ready to put the hard pipe back on with the bead of rtv and I drop a bolt. its getting dark I put the two bolts in I have and search franticly for the third. Roll the car back look around, look around the fascia, behind the intercooler, etc....Cant find it. So I stole a bolt off the AC system and put it in...I think it was the correct length it compressed the rtv and feels tight. So has anyone run into this problem...did the thermostat slide down and not allow the hard pipe to completely screw down...So now I just fill with coolant tomorrow and turn heat on full blast and open radiator cap and let it burb after I fill it...
Thanks

[RustspecS13]

Get one of those and bleed it with that.

A lot of nissans have the heater core above the top of the engine where coolant circulates. So its easy to get reduced heat and bubbles in the system.

You need a good T stat, and to make sure theres nothing blocking your radiator or heater core. Does the coolant look dirty at all when you drain it? Do you have really good heat?

If all that checks out, you just need to thoroughly bleed the system.

Or what kind of fans do you have? If you have a stock mechanical fan that's failing, you might not have enough air flow through the radiator. If your FMIC is blocking all airflow to the radiator.

~Alex

[gt28rsftw]

i had the problem where my tstat fell down a lil and when i tightened the bolts it looked good then i slugged them up and broke my tstat housing pipe for the lower hose. it sucked really bad lol. i parked with the from=nt end up on jack stands stupid high up and ran it for awhile and it got all the air out. and driving the car for a lil bit just check it after the first couple days and anyohter air will work its way out just keep checking for like a week to make sure nothing else is leaking anymore