boiling coolant and temp gauge fluctuating - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

aziankingz · 06-07-2009, 07:25 PM

I recently put in a new aluminum radiator (JVT racing 3 rows radiator) plus taurus fan. I bled it and it seems to not overheat, as per the stock temp gauge. While driving onto the highway the stock temp gauge suddenly drops to the first line and at a constant speed would be between the first and second line of the gauge. When on local roads it would go up to between the 3rd and 4th line, which I would say is normal, but when at a stop, the revs would kind of float at around 1500rpms and at times the idle would rise. I looked at the temp gauge and noticed that if i rev the needle would bounce from the 4th line then to the 2nd line then to 1st line then back up to the 4th line. Then I smelled coolant from time to time and when I finished driving to my destination (total of 20 mins on highway and 5 mins of local driving), i can hear coolant boiling in the reservoir, but the temp gauge shows no overheating. Any idea what is causing this issue?

Rapier46 · 06-07-2009, 07:48 PM

throw in an aftermarket temperture gauge and see what's really going on. stock ones aren't very accurate. sounds like a wiring issue. but if coolant is boiling the thats a problem aside from the gauge.

greddyguy · 06-07-2009, 08:00 PM

is this an SR or a KA? a friend of mine had the same problem, no matter how much he bled the system it would boil over.

aziankingz · 06-07-2009, 08:07 PM

its a ka24e

KiLLeR2001 · 06-07-2009, 11:32 PM

Sounds like there is still air bubbles in the system. Sometimes when the traditional bleeding method is not enough (bleeding from the bleeder screw) I like to turn the heat on and have the radiator cap off. Air bubbles tend to surface.

hegamiz · 06-08-2009, 12:04 AM

definitely, just got a mishimoto rad on friday, my first time bleeding a coolant system, did a damn good job i guess... i used THIS for reference. and THIS vid.

I LUV MY S13 · 06-08-2009, 12:09 AM

i had a similar issue after i bled it..went away within like 4 days..

DataXUnknown · 06-08-2009, 03:10 AM

i had a similar issue, i ran it with the heater on full blast and my motor still blew up. (stock temp gauge is a POS, dont trust it

)

aziankingz · 06-08-2009, 11:31 AM

the way i bled it, i never used the bleeder screw.. just filled up, turned heater on, rad cap off, let car run, rev it at times to release air, checked lower hose if still cold (to check if thermostat opened - which took about 10-15 mins until lower hose was warm/hot) and waited for the bubbles to stop coming out..

06-07-2009, 07:25 PM	#1
aziankingz Nissanaholic! Join Date: Oct 2007 Location: NYC Age: 41 Posts: 1,735 Trader Rating: (28) Feedback Score: 28 reviews	boiling coolant and temp gauge fluctuating I recently put in a new aluminum radiator (JVT racing 3 rows radiator) plus taurus fan. I bled it and it seems to not overheat, as per the stock temp gauge. While driving onto the highway the stock temp gauge suddenly drops to the first line and at a constant speed would be between the first and second line of the gauge. When on local roads it would go up to between the 3rd and 4th line, which I would say is normal, but when at a stop, the revs would kind of float at around 1500rpms and at times the idle would rise. I looked at the temp gauge and noticed that if i rev the needle would bounce from the 4th line then to the 2nd line then to 1st line then back up to the 4th line. Then I smelled coolant from time to time and when I finished driving to my destination (total of 20 mins on highway and 5 mins of local driving), i can hear coolant boiling in the reservoir, but the temp gauge shows no overheating. Any idea what is causing this issue?

06-07-2009, 07:48 PM	#2
Rapier46 Zilvia Member Join Date: Oct 2008 Location: Calgary Age: 34 Posts: 260 Trader Rating: (0) Feedback Score: 0 reviews	throw in an aftermarket temperture gauge and see what's really going on. stock ones aren't very accurate. sounds like a wiring issue. but if coolant is boiling the thats a problem aside from the gauge. __________________ Left hand drive 240sx's ARE NOT SILVIAS.

06-07-2009, 11:32 PM	#5
KiLLeR2001 Post Whore! Join Date: Jun 2007 Location: オーランドフロリダ Posts: 7,955 Trader Rating: (46) Feedback Score: 46 reviews	Sounds like there is still air bubbles in the system. Sometimes when the traditional bleeding method is not enough (bleeding from the bleeder screw) I like to turn the heat on and have the radiator cap off. Air bubbles tend to surface. __________________

06-08-2009, 12:04 AM	#6
hegamiz Zilvia Member Join Date: Apr 2006 Location: Bakersfield/SoCal Age: 36 Posts: 270 Trader Rating: (9) Feedback Score: 9 reviews	definitely, just got a mishimoto rad on friday, my first time bleeding a coolant system, did a damn good job i guess... i used THIS for reference. and THIS vid. __________________

06-08-2009, 12:09 AM	#7
I LUV MY S13 Post Whore! Join Date: Dec 2008 Location: Norwalk, Los Angeles Age: 35 Posts: 3,349 Trader Rating: (35) Rides Gallery: I LUV MY S13 Feedback Score: 35 reviews	i had a similar issue after i bled it..went away within like 4 days.. __________________ -Jorge

06-07-2009, 08:00 PM	#3
greddyguy Zilvia Member Join Date: Dec 2007 Location: boise idaho Age: 37 Posts: 175 Trader Rating: (0) Feedback Score: 0 reviews	is this an SR or a KA? a friend of mine had the same problem, no matter how much he bled the system it would boil over.

06-07-2009, 08:07 PM	#4
aziankingz Nissanaholic! Join Date: Oct 2007 Location: NYC Age: 41 Posts: 1,735 Trader Rating: (28) Feedback Score: 28 reviews	its a ka24e

06-08-2009, 03:10 AM	#8
DataXUnknown Post Whore! Join Date: Sep 2006 Location: Mission Viejo, CA Age: 35 Posts: 2,934 Trader Rating: (30) Rides Gallery: DataXUnknown Feedback Score: 30 reviews	i had a similar issue, i ran it with the heater on full blast and my motor still blew up. (stock temp gauge is a POS, dont trust it )

06-08-2009, 11:31 AM	#9
aziankingz Nissanaholic! Join Date: Oct 2007 Location: NYC Age: 41 Posts: 1,735 Trader Rating: (28) Feedback Score: 28 reviews	the way i bled it, i never used the bleeder screw.. just filled up, turned heater on, rad cap off, let car run, rev it at times to release air, checked lower hose if still cold (to check if thermostat opened - which took about 10-15 mins until lower hose was warm/hot) and waited for the bubbles to stop coming out..