HELP!!! Overheating while driving... - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

blubottlemax · 07-25-2004, 10:38 PM

I just swapped a lower milage KA motor and 5spd into my car. Replaced the thermostat before installing it. Starting it up, everything idled fine, temp was fine. Drove it around, a couple minutes later, temp starts climbing. I pulled over, checked the radiator level, topped it off (it was a tiny bit low, but not by much), started it up, and let it idle for a few minutes. Temp was fine, then, I started driving it again and it started overheating about 50 yards down the road. Stock fans in place, aux fan was kicking on, I don't have the hood on right now, but I didn't think it would affect it that bad that quickly. Any ideas, I need to get this fixed tonight!!! Thanks in advance.

KA24DESOneThree · 07-25-2004, 10:43 PM

You bled the coolant, right?

blubottlemax · 07-25-2004, 10:47 PM

As far as I can tell. The manual says it takes 7 quarts, it only took about 5 1/2 I think. Then I started it up, let it run until the thermostat should have opened. It only went down a little bit. Then we topped it off again. Any other way to bleed the system? I just pulled the cap again, and its full. Overflow bottle is full as well.

91rusty240sx · 07-26-2004, 01:14 AM

did you install the thermostat on backwards?

SirWarrior · 07-26-2004, 05:00 AM

sounds like air bubble to me.
bleed it again and again, or take it to a mechanic and let them doit.

BSeay · 07-26-2004, 08:06 AM

I'm having the same problem but i had my thermostat replaced on tuesday (local shop) and i worked fine until now. I was driving home from work and it would slowly climb then the fan would come on and it would go down but when the fan cut off it would climb back up to the H... i dont know what the hells going on...

HELP ME PLEASE!!! 1995 240 w/ KA

nissantuner22 · 07-26-2004, 08:34 AM

run your heater on full blast for awhile. than check the level of the fluid.

turbo240sx · 07-26-2004, 08:36 AM

because the stat is on the bottom hose and not on top like most cars the bleeding proc takes a while. i jacked up the front of the car as high as i could to get the air pocket to rise up and then you have to just keep filling and squeezing the bottom hose until no more air bubbles come out of the radiator. this way works well but it just takes a long time. unless you have the tool that the dealerships use. with the air compressor. takes all of 5 min that way.

blubottlemax · 07-26-2004, 09:45 AM

Well I pulled the thermostat and everything looked fine, so I pulled the one off my old engine and installed it. Let it idle for a while, fans kicked on and the thermostat opened. Drove it around for a couple minutes and it didn't overheat again. I think the thermostat I was using wasn't opening, but we'll see. The RTV on the thermostat housing didn't seal right, so we have to pull it off tonight and redo it...

omen2853 · 07-26-2004, 09:52 AM

did you get all the air out? try this...follow the upper radiator hose. it connects to a metal tube thing that connects to where you installed the thermost. theres a little screw on the top of it. open that screw (make sure your car is cold) then take off your radiator cap. pour coolant into the screw hole. when you see coolant coming out of the screw hole, plug everything up.

same thing happened to me awhile back. i guess because of the air in that passageway where the screw is, the coolant cant reach the thermostat telling it to open or close. youll see what i mean when you look at it. hop ethat helps.

blubottlemax · 07-27-2004, 01:12 AM

Well I got the thermostat housing resealed, filled it up with coolant again (removed the fill plug and filled through the radiator till coolant came out) Started it up and let it idle and warm up. Even after the secondary fan kicked on, the coolant was not flowing properly. The lower hose never got hot, and I could not get the heater lines to warm up either. I'm assuming at this point that A: The water pump somehow is completely shot on a 60k mile motor or B: There is a blockage somewhere. We called it quits for the night since the motor was so warm. It never overheated, but you could feel the heat coming off of it. Tomorrow, I'm going to pull the thermostat and run water through a hose through the thermostat housing. If water comes out the other end, the water pump is probably shot. If it doesn't, then we have a blockage somewhere. Sound like a good idea? Anyone else have any ideas? I really need to get this fixed, any help much appreciated.

Dunkee · 07-27-2004, 07:27 AM

My cars been overheating for about a month now. It's weird cause I start it, drive for a while, temp shoots up to H...then about a minute later comes back down? Doesn't come up again unless I shut the car off and start it up again. I think it's my radiator cause its all corroded inside. Changed my thermostat about 4 times already. Maybe rad will fix this crazy prob.

blubottlemax · 07-28-2004, 12:02 AM

Problem fixed. Air was in the system. What a pain in the ass. Thanks for the responses.

07-25-2004, 10:38 PM	#1
blubottlemax Leaky Injector Join Date: Aug 2003 Location: Kent, WA Age: 46 Posts: 119 Trader Rating: (0) Feedback Score: 0 reviews	HELP!!! Overheating while driving... I just swapped a lower milage KA motor and 5spd into my car. Replaced the thermostat before installing it. Starting it up, everything idled fine, temp was fine. Drove it around, a couple minutes later, temp starts climbing. I pulled over, checked the radiator level, topped it off (it was a tiny bit low, but not by much), started it up, and let it idle for a few minutes. Temp was fine, then, I started driving it again and it started overheating about 50 yards down the road. Stock fans in place, aux fan was kicking on, I don't have the hood on right now, but I didn't think it would affect it that bad that quickly. Any ideas, I need to get this fixed tonight!!! Thanks in advance. __________________ 95 240sx Got KA-t?

07-25-2004, 10:47 PM	#3
blubottlemax Leaky Injector Join Date: Aug 2003 Location: Kent, WA Age: 46 Posts: 119 Trader Rating: (0) Feedback Score: 0 reviews	As far as I can tell. The manual says it takes 7 quarts, it only took about 5 1/2 I think. Then I started it up, let it run until the thermostat should have opened. It only went down a little bit. Then we topped it off again. Any other way to bleed the system? I just pulled the cap again, and its full. Overflow bottle is full as well. __________________ 95 240sx Got KA-t?

07-26-2004, 01:14 AM	#4
91rusty240sx Zilvia Junkie Join Date: Oct 2003 Location: Los Angeles, CA Age: 38 Posts: 467 Trader Rating: (1) Feedback Score: 1 reviews	did you install the thermostat on backwards? __________________ Tony

07-26-2004, 08:06 AM	#6
BSeay Users Awaiting Email Confirmation Join Date: Mar 2003 Location: Richmond, VA Age: 41 Posts: 634 Trader Rating: (0) Feedback Score: 0 reviews	I'm having the same problem but i had my thermostat replaced on tuesday (local shop) and i worked fine until now. I was driving home from work and it would slowly climb then the fan would come on and it would go down but when the fan cut off it would climb back up to the H... i dont know what the hells going on... HELP ME PLEASE!!! 1995 240 w/ KA __________________ 1995 240SX SE - Sold

07-26-2004, 08:34 AM	#7
nissantuner22 Zilvia FREAK! Join Date: Mar 2004 Location: Gainesville, Fl Age: 39 Posts: 1,056 Trader Rating: (-1) Feedback Score: -1 reviews	run your heater on full blast for awhile. than check the level of the fluid. __________________ Current Project: Operation: N/A SR: 93 Silvia Q SR20DE Engine with go fast goodies. , "Common problems 240sx's suffer from are curbs, trees, ditches, and other immovable objects."thx247 "on the tounge... there is no guardrails."- citizen

07-25-2004, 10:43 PM	#2
KA24DESOneThree Post Whore! Join Date: Feb 2004 Location: SD County SoCal Age: 38 Posts: 2,555 Trader Rating: (2) Rides Gallery: KA24DESOneThree Feedback Score: 2 reviews	You bled the coolant, right?

07-26-2004, 05:00 AM	#5
SirWarrior Zilvia Addict Join Date: May 2004 Location: Chicagoland Posts: 762 Trader Rating: (0) Feedback Score: 0 reviews	sounds like air bubble to me. bleed it again and again, or take it to a mechanic and let them doit.

07-26-2004, 08:36 AM	#8
turbo240sx Zilvia Member Join Date: Oct 2002 Location: CT Posts: 166 Trader Rating: (0) Feedback Score: 0 reviews	because the stat is on the bottom hose and not on top like most cars the bleeding proc takes a while. i jacked up the front of the car as high as i could to get the air pocket to rise up and then you have to just keep filling and squeezing the bottom hose until no more air bubbles come out of the radiator. this way works well but it just takes a long time. unless you have the tool that the dealerships use. with the air compressor. takes all of 5 min that way. __________________ 240sx s-13 TURBO weekend v-8 killer 90 Talon TSI WARNING.THIS CAR IS EQUIPPED WITH A TURBOCHARGER. DUE TO POSSIBLE BREATHING PROBLEMS UNDER HEAVY ACCELERATION, ALL FEMALES ARE ADVISED TO REMOVE ANY TIGHT FITTING OR RESTRICTIVE CLOTHING FOR SAFETY.

07-26-2004, 09:45 AM	#9
blubottlemax Leaky Injector Join Date: Aug 2003 Location: Kent, WA Age: 46 Posts: 119 Trader Rating: (0) Feedback Score: 0 reviews	Well I pulled the thermostat and everything looked fine, so I pulled the one off my old engine and installed it. Let it idle for a while, fans kicked on and the thermostat opened. Drove it around for a couple minutes and it didn't overheat again. I think the thermostat I was using wasn't opening, but we'll see. The RTV on the thermostat housing didn't seal right, so we have to pull it off tonight and redo it... __________________ 95 240sx Got KA-t?

07-26-2004, 09:52 AM	#10
omen2853 Zilvia Junkie Join Date: Apr 2003 Location: california, usa Age: 43 Posts: 316 Trader Rating: (0) Feedback Score: 0 reviews	did you get all the air out? try this...follow the upper radiator hose. it connects to a metal tube thing that connects to where you installed the thermost. theres a little screw on the top of it. open that screw (make sure your car is cold) then take off your radiator cap. pour coolant into the screw hole. when you see coolant coming out of the screw hole, plug everything up. same thing happened to me awhile back. i guess because of the air in that passageway where the screw is, the coolant cant reach the thermostat telling it to open or close. youll see what i mean when you look at it. hop ethat helps.

07-27-2004, 01:12 AM	#11
blubottlemax Leaky Injector Join Date: Aug 2003 Location: Kent, WA Age: 46 Posts: 119 Trader Rating: (0) Feedback Score: 0 reviews	Well I got the thermostat housing resealed, filled it up with coolant again (removed the fill plug and filled through the radiator till coolant came out) Started it up and let it idle and warm up. Even after the secondary fan kicked on, the coolant was not flowing properly. The lower hose never got hot, and I could not get the heater lines to warm up either. I'm assuming at this point that A: The water pump somehow is completely shot on a 60k mile motor or B: There is a blockage somewhere. We called it quits for the night since the motor was so warm. It never overheated, but you could feel the heat coming off of it. Tomorrow, I'm going to pull the thermostat and run water through a hose through the thermostat housing. If water comes out the other end, the water pump is probably shot. If it doesn't, then we have a blockage somewhere. Sound like a good idea? Anyone else have any ideas? I really need to get this fixed, any help much appreciated. __________________ 95 240sx Got KA-t?

07-27-2004, 07:27 AM	#12
Dunkee Zilvia Addict Join Date: Mar 2002 Location: NJ Age: 45 Posts: 848 Trader Rating: (1) Feedback Score: 1 reviews	My cars been overheating for about a month now. It's weird cause I start it, drive for a while, temp shoots up to H...then about a minute later comes back down? Doesn't come up again unless I shut the car off and start it up again. I think it's my radiator cause its all corroded inside. Changed my thermostat about 4 times already. Maybe rad will fix this crazy prob. __________________ 96 SE http://www.cardomain.com/ride/255381

07-28-2004, 12:02 AM	#13
blubottlemax Leaky Injector Join Date: Aug 2003 Location: Kent, WA Age: 46 Posts: 119 Trader Rating: (0) Feedback Score: 0 reviews	Problem fixed. Air was in the system. What a pain in the ass. Thanks for the responses. __________________ 95 240sx Got KA-t?