rb25det overheating on start up

[thrasher324]

last night was the first time overheating but i was just driving in my neighborhood and i noticed my temp gauge was over 250 degrees. the funny thing is that the car ran fine. and this morning on start up i turned the car on to warm it up and the temp gauge was going over 250 again but when i drove it for a bit it went back to 180. you guys think its a bad gauge? its never done this before and its not like i push my car

thanks for ze help

[Couped_up'd]

Bad gauge or you got a HUGE air bubble in the coolant system. Bleed the coolant system.

[thrasher324]

Bad gauge or you got a HUGE air bubble in the coolant system. Bleed the coolant system.

does having air bubbles in the coolant system usually happen?

[Couped_up'd]

does having air bubbles in the coolant system usually happen?


Yes =/ I have had 2 of the 5 rb's I own do it.

[thrasher324]

so when my temp gauge saids its over 250 degrees, is it really over 250 degrees? or its just because its reading the air bubbles too. and i guess when i start driving i get the water & the air bubbles circulated around the engine so it reads the right water temperature? am i right? llol idk if that made sense

[OBEEWON]

Possible. Jack the front up and turn the heat on full blast. Make sure you have no leaks anywhere or air will continue to get into the system.

[thrasher324]

Possible. Jack the front up and turn the heat on full blast. Make sure you have no leaks anywhere or air will continue to get into the system.

hmm, i will try that right now actually.
but i got some new coolant and i was gonna flush the old one out but nothing came out. i have a mishimoto radiator. and also when i looked inside the radiator and squeezed the radiator hose all that came out was just really dirty black coolant. i drove it after this and my temperature gauge kept jumping up and down and if i idle it overheated. its weird though because the engine is fine and it drives fine. no smokes what so ever.

just talked to a 240 guy that my friend knows and he said the radiator hose or the radiator itself can be clogged...thats what it seems like to me since nothing came out of the drain plug.


help needed asap!

[OBEEWON]

Try the Prestone reverse flush kit. Im giong to be trying that on mine when my water hose isnt frozen. Rust can build up in the coolant passages.

[thrasher324]

Try the Prestone reverse flush kit. Im giong to be trying that on mine when my water hose isnt frozen. Rust can build up in the coolant passages.


i actually got that today...with the T fittings or what not.. but uh using the water hose shouldnt be a problem right? cuz i mean its not like its pushing 100psi of water unlike some shops with pressurized water

[OBEEWON]

i actually got that today...with the T fittings or what not.. but uh using the water hose shouldnt be a problem right? cuz i mean its not like its pushing 100psi of water unlike some shops with pressurized water

Where did you get it? Lol I cant find one now. Ive heard people scared it might damage stuff but more that say it wont. Just don't put it on full blast. Garden hose should be ok.

[ImpulseCars]

so your coolant is contaminated and your car is over heating even at idle? sounds like head gasket could be trouble.

where is the water temperature sensor located for you?

[nyc240sx]

listen put new coolant in the system make sure your water pump is good and your thermostat use the stock clutch fan if you want your temps safe jack the front off the car as high as you can put heat on full blast open radiator cap or coolant bottle where you fill it up to let the bubbles escape then start squeezing your top radiator hose for about 20-30 minutes keep checking your temps get a autometer mechanical water temp guage normal it should be at 176 always sometimes goes up to 180 at high speeds nothing over than that..so squeeze all of your coolant hoses mostly the upper one u will see alot of bubbles coming out do this for about 20 minutes or so your car will run excellent dont use those electrical fans to cool your system there not good enough slip on the clutch fan

[OBEEWON]

dont use those electrical fans to cool your system there not good enough slip on the clutch fan

Pics of your engine bay? Is your motor in an S-chassis because I've never seen room enough for a clutch.

[thrasher324]

yea its a s13http://i41.tinypic.com/2m7f47o.jpg

http://i39.tinypic.com/2lkvc5j.jpg

[nyc240sx]

looks good do what i said in my previous post and your car will run perfect

[OBEEWON]

As is he has no room for a clutch fan.

[thrasher324]

i think im gonna wait till monday so my auto tech teacher can help me out wit hthe flush...but i wanna be able to drive this thing but idk if i can do it myself safely

[Norty]

Sounds to me like a bad sensor or grounding issue. The gauges ground through the temp sensor so it might be shorting or something. IF you are just starting the car and it is doing this I would say definetly gauge/sensor problem. Even with no water in the cooling system at all it would take at least 10 min or more to actually get hot. It takes a few min just to get the metal warm much less hot!

[thrasher324]

Sounds to me like a bad sensor or grounding issue. The gauges ground through the temp sensor so it might be shorting or something. IF you are just starting the car and it is doing this I would say definetly gauge/sensor problem. Even with no water in the cooling system at all it would take at least 10 min or more to actually get hot. It takes a few min just to get the metal warm much less hot!


true...i am planning on replacing the thermostat also

[WhipsGoneWild.net]

sry to bump old thread guys but my cars been overheating for a little while now..

-when i bought it i blew 3 stock plastic radiators
-i flushed the system
-replaced the radiator with cx racing and got nismo thermostat and still does it
-i mean the cooling system isnt very complicated but i dont think its the pump or a block or a head gasket.
-i have 2 small pusher fans that run constantly (no shroud)
-my battery voltage from pfc reads 12.5-13.2 idk if thats super low
-it runs fine on the highway but when it starts to get warm >220F it tends to run lean (my car needs tune as well but have to fix overheating before i start beating on it)
-I spoke to a buddy that has 2j in s14 and said his overheated then he got 1 large fan with shroud and took care of the problem.

does anyone have any advice?