Here we go, overheating woes...the end of my poor 240?

[nismoracingsx]

turned out my rad cap was bad car runs 10 degrees warmer b/c of the new thermostat (which was expected) but other than that, ran great the whole hour drive to school.

[Slappy]

Ahh , bad rad cap , alot of people dont realize that can be a problem.Glad its running ok. I feel stupid that i forgot to mention replacing the rad cap 1st.

[Jadesr20det]

i would hate to think that my brand new nismo rad cap is bad lol

[Slappy]

i would hate to think that my brand new nismo rad cap is bad lol

Aftermarket rad caps are'nt always a good idea. They hold TO much pressure , wich causes the thermastat to open ealier and can cause hoses to blow.

[nismoracingsx]

final follow up on my thread of woes

with the coolant system repair my mileage has shot back up to where it was when i bought it

right before my radiator cracked, i was getting about 320 to the tank (thats with the gas light coming on)

Right now, i still have about 1/10th of a tank left and already at about 340, aiming for about 360 miles for this tank (this includes spirited driving, city driving, and 75mph highway speeds) so cooling maintenance ftw

[Jadesr20det]

Aftermarket rad caps are'nt always a good idea. They hold TO much pressure , wich causes the thermastat to open ealier and can cause hoses to blow.

yea i know that to be true. i just sat outside for anothe hour rebleeding the system and havent had another issue yet. i think my car just doesnt like sitting around not being driven for awhile lol.

[BigLoukaT]

Out of curiosity, what coolant temp sensor did you replace for $6? Courtesy Nissan sells the ECTS for $24 dollars here (http://www.courtesyparts.com/betasite/2 ... cPath=1418&)

Did you replace the Coolant temp sensor that the ecu uses, or the one the gauge cluster uses?

[nismoracingsx]

replaced the one with the orange plug

HORRIBLE UPDATE

Car ran purrfect all week. Went to a city about an hour away today to buy some stuff, drove there perfect...sat in traffic perfect...parked it for about half an hour. Get in the car and start driving to the other side of town...look down and temp is way up

Pull over, shut car off, pop hood. Overflow is pretty full of coolant, top hose nice and stiff, clutch fan and ac fan are both running

BUT

This time the overheating is MUCH more predictable...when idling it gets hot, if revved or driving around 50+ mph the temp will stay on the 3rd mark...

Parts that were already replaced in the previous repair:Radiator CapRadiatorWater PumpThermostatCoolant Temp Sensor

For the minute or two I had it in the yard (before i had to shut it off) i revved it up a little bit and not a lick of smoke out of the exhaust, and no smell of coolant.

The only thing i can think of is my clutch is toasted for my cooling fan?? If it was bad, would it still spin, just not fast or consistant enough? I think its the only thing that hasn't been replaced or am i missing something?? My car was running so perfect, shoot me some ideas guys Thx for the all the posts and comments on this thread btw

[nismoracingsx]

morning bump, any other ideas? i'm waiting for it to warm up a little bit before i head out there.

Any other possibility besides teh fan clutch??

[xekushnr]

i wrote out a big long post, clicked the button, and found out i wasnt logged in. so im going to paraphrase. you should be thankful, because i was pretty ticked and almost didnt bother trying to post again.

some possible causes to your overheating:

- low coolant (you probably have that covered..just listing everything i can think of)- stuck thermostat (take it out, throw it in a pot of water and set it to boil, watch the thermostat, it should open a bit before the water boils)- retarded ignition timing- loose fan belt-bad water pump-fan clutch (if its stuck it will change speed with the engine RPM, very dangerous)- rust in the radiator

also, DONT turn your car off when it starts overheating. since the coolant is not circulating and its sitting in a very hot water jacket, it will start to boil. the engine will actually get significantly hotter before it cools down. and, as we know, heat warps heads, and warping means more time and money down the drain.

[nismoracingsx]

replaced the fan clutch, no overheating (AGAIN). The new fan clutch is beefier as well, i noticed...This thread is getting super long thx for all the ideas guys. Plan on replacing the fan with electric some time in the future (might as well, since i've been doing cooling work like past 2 weeks). Noticed my clutch fan had some cracks in it, but no parts stores had a replacement, so i guess i'm gonna have to eyeball it until its replaced..

[nismoracingsx]

bump

I guess my 240 hates meh, it got hot sitting in taco bell drive thru

Soon as I got on the open road, temp sat @ the third mark though...

I'm out of ideas completely...just about everything has been replaced and i know i'm not burning the coolant or anything, because the level doesn't move, my radiator is always slap full and theres no smoke from the exhaust...

Next weekend i'm going to look at a supra thats for sale...it will be my second dd, but if the 240 keeps this up, then i plan to just sell it, i live too far away from school and cannot afford to have a vehicle that keeps handing me one problem after another

It drove perfect for a whole week, and now its having problems again, any have ANY idea on something i overlooked?? Is there any way an air pocket could be lurking in there only to pop up a week later?

I'm tired of driving my car and feeling like i'm walking on egg shells

[Jadesr20det]

I feel the same way lol. I have an electric fan nismo cap,thermostat,koyo rad and still get bubbles in the system. I don notice that if the car sits a few days at a time thats when it happens other than that if i drive her everyday no problems. I also noticed if i tap my cluster the temp needle goes up and down so maybe swap different clusters and see if thats bad. Also check your temp coolant sensor (dont remember if it was mentioned before or not) gl

[sleepyS14]

if you're reallie concerned... you could always get that coolant dye tester stuff at pepboys or napa.. stays blue if you're good..or turns yellow if theres exhaust gases in your coolant (meaning head gasket). dont hold me to that . i think its like $20 ..maybe a little more. if you want to check it as a worst case scenario. then i think you're gonna have to do a coolant flush or at least a drain & fill after using the dye. if anything, check your mix. you running 50/50?. invest in a $10 bottle of watter wetter.. you'd be surprised.

good luck. believe me. i feel your overheating pains. 60 degrees out, 4in KOYO rad, 3 cooling fans, 1.3kg/cm2 greddy radiator cap and im still getting heat soak. jeeze.

[nismoracingsx]

whole system is practically brand new. I'll try bleeding it tonight, maybe an air pocket was hiding in there for a week will also throw a bottle of water wetter in there, maybe my mixture of coolant water is off, i just don't know It seems to only overheat after its been driving for a while and then sits in traffic or something for at least 20 minutes, then it will start having problems..

On a good note, i might pick up a MK II Supra next weekend 2 rwd dd's ftw

[xekushnr]

i dont know man. have you checked everything in my post? try testing the coolant temperature sensor and the 02 sensor with a voltmeter and make sure they are in spec. i cant really think of much else. i am willing to bet its either more air or its something in my last post.

[nismoracingsx]

coolant temp sensor is also new, but i'll look up how to test it, just in case..tried driving to school today and i only got 10 miles before i had to turn around and gimp it home...i don't think i've been this irritated and depressed in a lonnngggg time .

[xekushnr]

coolant temp sensor is also new, but i'll look up how to test it, just in case..tried driving to school today and i only got 10 miles before i had to turn around and gimp it home...i don't think i've been this irritated and depressed in a lonnngggg time .

try kicking it?

[nismoracingsx]

just tried bleeding the system, got some bubbles , drove it, it drove fine for like 5 miles...then it started heating up again...i don't get it anybody wanna buy an otherwise nice condition 240? email me

[xekushnr]

if you were closer i definately would...sounds like it runs fine minus the heating problem. seems like you are getting air every time you bleed...that must be the problem. we just have to figure out why you keep getting bubbles.

[nismoracingsx]

well, this is the final straw, tomorrow will be the 4th day of class i've missed and i'm already missing all kinds of grades because of this car. I took it to a shop today, they said that the engine itself is unharmed (no exhaust in the coolant or anything). They also said they couldn't see the coolant 'flowing' and tech said that he bets that i got either a bad thermostat from the store or the wrong type water pump.

well...i replaced teh thermostat today and i'm still having all kind of heating problems...

so tomorrow morning i'm going to pick up another vehicle (hopefully).

i feel bad bailing on this 240, but its crapping out on me at the worst possible time since its my dd, and i can't afford to put any more cash and school time into it.

[sleepyS14]

did you ever try running the car WITHOUT the thermostat? just a thought.

[Jadesr20det]

Imma switch out my waterpump then some hoses if that doesn't work then the car is gone for sure. Also gonna check on the coolant temp sensor thing is my car doesn't blow white smoke out no smell and it still runs w/o hesitation when its heating up. Idk what the hell it could be but an sc300 is lookin real damn good about now.

[oneline180]

try bypassing your heater core, thats what my car's problem was. i havent replaced it yet because i live in houston and its hot as **** here. It gets cold for about two weeks, thats it. I might get around to doing it... but then again, why bother...I dont see any benefit from it.

[Jadesr20det]

Found the issue today!!!!!! Two holes the size of pins in my heater hose (if your looking into your engine bay the hoses in the back of the motor) I noticed there was a sound coming from the engine bay that sounded like a sprinkler when it first gets going. Pop the hood a lo and behold follow the noise to the heater hose. So in short ill be switching that out this weekend and so should you nismoracing if I remember correctly that's one thing u never mentioned changing and we were having the same issues with air bubbles and heat. Holes in your heater hoses can create those bubbles and cause the coolant to leak out too.

[FUNS14]

Have you checked the thermostat?

[Jadesr20det]

Have you checked the thermostat?

I removed it all together so that couldn't be it. The heater hose leaking from 2 holes was causing my problem

[carbully]

xekushnr is right when earlier he was alliding to the fact that it would help to really know how hot it's getting. You are right, small holes in any hose can causeair to get sucked in when it cools off. How long ago did you remove the t-stat?

The reason I ask is that I have seen cars overheat becuase the t-stat was removed. The T-stat also serves as like a restrictor to the flow of coolant, and when removed the coolant does not spend enough time working though the radiator. So, instead of being cooled to say 160 on the cold side of the rad, it is being pushed out when it's still like 175 or so (numbers are for demonstration purposes only). So, don't be suprised if it overheats again until you put a new t-stat in there.

Also, another question was the coolant really rusty? I have seen the impeller fins on water pumops get rusted or even worn down if the WPis really old. At idle it turns really slow and it barely pumps. If your system was not all that rusty though it's probably ok.

[Jadesr20det]

thing

xekushnr is right when earlier he was alliding to the fact that it would help to really know how hot it's getting. You are right, small holes in any hose can causeair to get sucked in when it cools off. How long ago did you remove the t-stat?

The reason I ask is that I have seen cars overheat becuase the t-stat was removed. The T-stat also serves as like a restrictor to the flow of coolant, and when removed the coolant does not spend enough time working though the radiator. So, instead of being cooled to say 160 on the cold side of the rad, it is being pushed out when it's still like 175 or so (numbers are for demonstration purposes only). So, don't be suprised if it overheats again until you put a new t-stat in there.

Also, another question was the coolant really rusty? I have seen the impeller fins on water pumops get rusted or even worn down if the WPis really old. At idle it turns really slow and it barely pumps. If your system was not all that rusty though it's probably ok.

thing is i had a nismo t-stat in there b4 took it out about 2 days ago i even tested the stock one in hot water when i took the nismo out i tested that one also. Both passed w/the nismo opening a bit earlier (as its supposed to). My cooloant wasnt rusty as i bought a brand new koyo rad with the swap as for water pump i never had the heating issue till recently. The car idled for 1 hr outside no heating issue (w/heater on full blast). So while driving the car this morning it got hot i didnt panic just pulled over (in an retired persons trailer park). I hear this noise like a sprinkler starting up im thinking to myself "great now imma get soaked on top of everything" pop the hood follow the sound and see 2 pinhole sized holes in my one heater hose with coolant bubbling and hissing out of it (small amounts).Theres my problem because before that car ran perfect and when i added more water coolant on the way home no problems. So in conclusion the motor gets to operating temp coolant starts leaking out of said hose and slowly leaks out over a few days of driving when coolant runs dry car starts to heat up. End of story needless to say ill be changing it out this weekend