Replacing radiator fan assembly on Nissan Maxima

[Leros]

This is about a 2000 Nissan Maxima.

The car doesn't run as smooth as it used to. It has a vibration to it that comes and goes. Sometimes its there and sometimes it isn't. When you turn the A/C on, the vibration usually gets 10x worse. With the A/C on, its almost always vibrating, but occasionally it still runs smooth.

I've looked under the hood and seen that the one of the fans on the radiator assembly is really wobbly. I'm pretty sure all I need to do is replace that radiator fan assembly.

I don't have physical access to the car. Can anybody give me an idea of how difficult this will be to fix? I don't want to be taking out the whole radiator or anything like that.


Update

I replaced the radiator fan today.

I had to remove two screws to remove the air intake which was in the way and two bolts to unhook the fan assembly. After unhooking the wires and unclipping a few hoses, the fan assembly just lifted out.

I did have remove the upper radiator hose to take out the fan assembly, which resulted in me leaking about 1qt of coolant all over the the ground. And reclipping the lower radiator hose was a pain, but I got it back in eventually.

All in all, it went pretty well. Took me about 30 minutes, 15 of which I spent trying to reclip that lower hose.

 

[CraigRT]

Should not be difficult.

Just a matter of removing the fan shroud and replacing.

I strongly suggest checking Maxima.org for some write ups on rad replacement if anything (to be guaranteed to find info on fan removal) Or perhaps there is a fan removal write up too, I don't know.

There are also FSMs (factory service manuals) at nicoclub.com. I used the 2K FSM to aid in replacing the water pump on my fathers' '00 Maxima.

 

[Leros]

Maxima.org is a great resource. Thanks.

It sounds like its really easy. A few wires and a few screws.

 

[CraigRT]

Maxima.org is a great resource. Thanks.

It sounds like its really easy. A few wires and a few screws.

That is pretty much all it should be honestly.. I have not had the fan shroud out in my '02 yet, but I would be surprised if it took more than 5-10 mins to remove honestly.

Only reason it may take more time is if you have to unhook anything from underneath the car, as opposed to from under the hood.

 

[SearchMaster]

Also, there are two fans. You should be able to disconnect the wobbly one and see if that solves the overall problem. I had a bad fan on mine and drove with one fan for about a week until I got the replacement; the temp stayed stable as long as I wasn't in bumper to bumper traffic for long, even then it never got dangerously high.

 

[Leros]

Also, there are two fans. You should be able to disconnect the wobbly one and see if that solves the overall problem. I had a bad fan on mine and drove with one fan for about a week until I got the replacement; the temp stayed stable as long as I wasn't in bumper to bumper traffic for long, even then it never got dangerously high.

It is only one of the fans. It seems like the problematic one is secondary and only comes on as the car gets hotter.

It only caused the car to get too hot when I was idling for a long time in 100+ degree heat. I just haven't been able to run the A/C unless I'm going 40+ without stopping.

Its been like this for a year now. I've just been too lazy to fix it. I'm about to drive from Austin to Seattle, which is what is prompting me to fix it.

Another question: The radiator fan would need to run extra when I have the A/C on, right? The vibrating usually goes away if I turn off the A/C and I have observed the secondary fan spinning up once I turn the A/C on. I guess the A/C is plugged into the radiator cooling line?

 

[Viperoni]

Your rubber radiator mounts are more likely to be the cause, but a defective fan would also cause it.

Are the fans dual speed or single speed on your max's? I know the ones on my 97 are duals. Does the primary fan spin up to high speed when the secondary fan comes on?

 

[jlee]

Something like this should keep it cool..

 

[CraigRT]

It is only one of the fans. It seems like the problematic one is secondary and only comes on as the car gets hotter.

It only caused the car to get too hot when I was idling for a long time in 100+ degree heat. I just haven't been able to run the A/C unless I'm going 40+ without stopping.

Its been like this for a year now. I've just been too lazy to fix it. I'm about to drive from Austin to Seattle, which is what is prompting me to fix it.

Another question: The radiator fan would need to run extra when I have the A/C on, right? The vibrating usually goes away if I turn off the A/C and I have observed the secondary fan spinning up once I turn the A/C on. I guess the A/C is plugged into the radiator cooling line?

On the Nissan, I believe one fan runs at all times when the A/C is on, unless you are going over a certain speed, and quite often both fans run with the A/C on. So yes, by not running the A/C, you are not forcing the one fan to turn on. The only time both fans run without the A/C is when the cooling system is struggling to get back to normal operating temp (usually only needs one fan to accomplish this)

 

[Leros]

On the Nissan, I believe one fan runs at all times when the A/C is on, unless you are going over a certain speed, and quite often both fans run with the A/C on. So yes, by not running the A/C, you are not forcing the one fan to turn on. The only time both fans run without the A/C is when the cooling system is struggling to get back to normal operating temp (usually only needs one fan to accomplish this)

Ok great. That is the behavior I'm seeing.

 

[Vette73]

Even if everybolt was loose on the Rad Fan support it would not cause the car to run different (good or bad). So I am not sure what you mean by "The car doesn't run as smooth as it used to."

 

[SearchMaster]

Even if everybolt was loose on the Rad Fan support it would not cause the car to run different (good or bad). So I am not sure what you mean by "The car doesn't run as smooth as it used to."

I think he's saying he can feel a noticeable vibration, presumably from the wobbly fan.

 

[nwfsnake]

It may be the fan, but I would suspect a bad motor mount or two causing the vibrations. Electric fans don't really vibrate that much, though they may be noisey. In any case, good luck!

 

[LTC8K6]

The rad fan motor in my Taurus is definitely the cause of a vibration. The bearings are shot and the motor is vibrating and you can easily feel it from the driver's seat. It's a pretty big motor and a pretty big fan, so the vibrations are strong.

 

[Leros]

It may be the fan, but I would suspect a bad motor mount or two causing the vibrations. Electric fans don't really vibrate that much, though they may be noisey. In any case, good luck!

You ever seen an a fan that rotates slightly off center? They can be very wobbly. And the wobbliness makes its rotation become even more off center with time.

 

[Raduque]

Not sure about the Maxima, but when I replaced the radiator on my Altima, all I had to do was unclip the wiring connectors from the fans, two bolts on top and then it lifted right off.

Oh and if you've got a vibration that's almost always there (even with the wobbly fan not running), you've probably got a motor mount that's bad or going bad.

 

[Leros]

I replaced the radiator fan today.

I had to remove two screws to remove the air intake which was in the way and two bolts to unhook the fan assembly. After unhooking the wires and unclipping a few hoses, the fan assembly just lifted out.

I did have remove the upper radiator hose to take out the fan assembly, which resulted in me leaking about 1qt of coolant all over the the ground. And reclipping the lower radiator hose was a pain, but I got it back in eventually.

All in all, it went pretty well. Took me about 30 minutes, 15 of which I spent trying to reclip that lower hose.

 

[thecoolnessrune]

Did it make a difference for you OP?

 

[Leros]

Did it make a difference for you OP?

Oh yeah. The car runs a lot smoother and quieter now. Not to mention, the A/C actually puts out cold air when I start it, instead of taking the usual 3 minutes to get cold.

The behavior of the fans changed too. Before I replaced it, one fan would come on, and then sometimes the other would come on too. Now, they both always run at the same speed. I looked it up and that is how it suppose to operate. I guess the second fan was dying on me.

 

[thecoolnessrune]

Oh yeah. The car runs a lot smoother and quieter now. Not to mention, the A/C actually puts out cold air when I start it, instead of taking the usual 3 minutes to get cold.

The behavior of the fans changed too. Before I replaced it, one fan would come on, and then sometimes the other would come on too. Now, they both always run at the same speed. I looked it up and that is how it suppose to operate. I guess the second fan was dying on me.

Awesome OP :thumbsup;

I know on the cars I've seen, usually one fan always runs and then when the AC is turned on both are set to always on (to ensure maximum AC output). When the AC is off and the car is driving, then the second fan coming on depends on the temperature of the coolant.

But I've had pretty limited exposure to compact cars. Admittedly, most of the engine bays I've been in have clutch fans acting as the flywheel.