Alright so here's whats going on.
last week as i was driving home in stop-n-go traffic i noticed my car was overheating (needle was at about 3/4). I turn off the air and turn on the heater which brought the temp down slowly.
after a week of trouble shooting. i realized the the car only overheated in traffic (slow driving) only if i had the AC on. I also noticed that only one fan was working. at normal operating temp. i wasn't sure if the other fan only runs at higher temp or not.
over the weekend i pulled out the thermostat and i found what seems to be a piece of gasket in the spring, it wasn't big enough to stop the spring from moving or anything i figure it was opening fine.
Ii proceeded to drain the radiator and filled it with some coolant system i got at autozone.
yesterday as i was driving home i monitored the temp the whole time. at the beginning it was a bit irradic (bouncing between 1/4-3/8) then it stabilized just below 1/2. when i got home i went inside for a minute and when i came back out there was a puddle of water under my car =/. i turned it on and only one fan was running. temp guage was normal. i turn off the car and found that the radiator now has a crack in the top right ( nearest battery).

anyone know what could have cause this? are both fans supposed to be on at same time?

 

U need a new radiator and a complete flush of the cooling system. Choose Nissan Long Life Coolant (not some OTC coolant that is incompatible with the aluminium and seal chemistry of vehicle).

 

Yeah, Im ordering the new radiator Tomorrow. any recommendation for where/brand to buy?

Im still concerned about the fans though. any input on that?

Thanks Much appreciated

 

I am not a Maxima cooling expert, but from my days working on Hondas and Acuras one fan only is dedicated towards cooling the radiator.

The other fan is strictly for the A/C system and is only activated when the A/C is running.

Not matter how hot the car is only one fan would run if the A/C was off.

However, no matter what the temp of the car is when the A/C is on both fans would run.

These 2 fans would help cool both the radiator (which runs hotter woth A/C on) and the condensor so you are oprovided with cool A/C.

I assume that Maximas are the same.

Hope this helps.

 

contrary to this, I've noticed both fans running on my max, even when the AC was never on..I guess someone can chime in ?

 

yes please, could someone please confirm or clarify the operation of the fans.

Also, Any recommendation on the radiator?

ohh yeah has any one else had their temp gauge bounce like mine did it was really weird. do i need to replace the temp sensor? i'm afraid i has been giving me faulty reads now.

 

in the summer both fans are supposed to be on. one of my fans (the one on the driver side) is the main cooling fan which is supposed to come on when its hot. the other fan is the a/c fan. My cooling fan works half the time so when it doesn't work, and the car isn't moving (so lesser airflow), i start heating up and warm air comes out inside even with the a/c on. The temp gauge bounces because the coolant temperature is changing, not because the gauge is broken...

as for radiator brands, just buy an OEM for $150.

the cooling fans also turn off at a certain highway speed to save power, and because the wind from your high speed is enough to cool the radiator itself, which is why you see these heating problems in stop/go traffic.

 

I recently had to replace both my fans, since they stopped working entirely and my car would overheat. I have noticed now that both of the fans activate when it reaches a certain heat level(aobut 1/2 way) to cool down the car, even when the A/C is off. When the AC is on, both fans are on at full blast all the time. Dave B. is always recommended when it comes to large buys like this. He saved me about 90 dollars compared to my local dealership(and had the item in stock when my dealership did not).

 

the bouncing was quite erratic, like up and down in a second i have a video just not sure how to post it (gonna look into it). you maybe right though.

the fan that wasn't running was the drivers side, so i guess ill have to replace it. can i do the individual or do i have to replace the assembly (both). are they on the same relay?

im probably just gonna order the Koyo i found for $140 shipped...Called dealer and they wanted $630 .

 

Thanks, just asked Dave for a quote. Clean car by the way

 

This has already been covered before.......BOTH fans operate (OFF, LOW, or HIGH) together, and the operation of the fans is dependant on coolant temp, car speed, AC off or on, and the refrigerent high-side pressure.

 

Make sure you are burping your cooling system too.

 

did you call him or did you pm him here on the org? if you want to call him then it will be Dave Burnett (sp?) at 1-888-254-6060
and thanks for the compliment

 

If you need new radiator, then just get the Koyo at the Group Deal section for $150 shipped I believe.

 

I would bet the bouncing was due to pockets of air in the coolant as he just drained and filled.

To the OP. I hope you also replaced your T-Stat after observing the gasket issue.

Dont forget to burp the system correctly to get all the air out prior to a long drive with your new radiator.

 

Well i removed the gasket debris, should i change the T-stat while I'm at it? it looked ok. Has anyone had problems with the Auto zone ones?

Im looking up how to properly burp the system now. I've ordered the Parts Already (fan, and radiator).

Since I already have the car on jack im changing the Belts too they are way overdue.

 

good luck...and keep us posted!

 

I installed everything last night. I replaced the Radiator, Fans assembly, thermostat, drive belts and i even did my front brake pads and all for under $500. man was i tired by 10:30pm. haha the Power Steering belt was such a pain.

Everything works perfect .

Next up:

(9-10-09)
Tokico Illuminas and Tien S-techs
(9-26-09)

New Rotor

 

I hope you looked into prices got the OEM thermostat. I have had problems with the autozone t-stats. I flushed the coolant system on my '99 and changed the t-stat with one from Autozone. It started over heating shortly after when I would sit in traffic. Swithched to the OEM t-stat and everything was fine after that.

Surprisingly the OEM was only $2 more than autozone.

 

ohh, i got the one from Autozone =/. It was only 16.99. If i have problems with overheating again ill definitely know where to start thanks though.

 

$19.17 at courtesy (plus shipping) if you need to replace it.

http://www.courtesyparts.com/kb_sear....php?keywords=[21200]+\(a33b&cPath=1956_1957_1981_1984

 

$15.97 at nissanpartsonline dot net.

They don't have such nice search as courtesyparts, but prices are lower + free shipping after $25.

 

So far so good. Thanks for all your help guys!

 

I have 280,000 miles on my Maxima, and recently i kept smelling coolant. Then the other day waiting at a light I felt a thump, it was the engine, i was overheating. I pulled over and noticed steam and a leak from radiator. I barley got it home while stopping to fill with water. So i got a new radiator and hoses and installed. Everything was fine and running well. But it started to rise in temp 3/4 when at traffic light. If I go down hill it goes back to1/2 temp. Could this be the thermostat bad? Or is this air pockets that need to be bleed out? Very Curious

 

check your fans. make sure they are both working

 

Ditto on the fans, but from everything I've heard you probably do have air in the system and have to work hard to get it out.

 

Soo yeah... just had to replace my ****ty autozone t-stat. went back to oem. suck too because i was like 50 miles from home, just as i was getting to the Smokeout tour, which was crazy! but yeah be forwarnd about those t-stats.

 

just to confirm your fans, it is not unusual to have only one fan running at a time. If it is not warm out or the a/c is not on, then you will typically only be using one fan

 

How do you Burp the system? I'm about to do my Radiator/Thermostat today.
Thanks

 

two fans should be both working not one.

 

Yes, they both should be in operating condition. But, as mentioned above, they don't necessarily have to be working at the same time, all the time. It depends on the demands of the vehicle.

 

you say that, but I've never seen one fan working and the other not. in the service manual it says hign and low, no one fan or two fans.

 

I have seen one fan working and not the other (when car reaches normal operating temp), two fans working (normal operating temp and A/C on) and no fan working in my car (such as when starting the car in the morning). If your fans are both working all the time, regardless of whether you're starting the engine after sitting overnight, or after a city commute with the A/C on, then something is not quite right with the operation of your fans.