replacing fan clutch/coupling - How to's

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Cliff_Jumper
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replacing fan clutch/coupling - How to's

Postby Cliff_Jumper » Sun Feb 13, 2011 6:26 am

Just replaced the fan clutch over the weekend and it is not that hard to do.

Here's a step-by-step how to so you can do-it yourself.

First, take off the metal cover underneath the engine. Take the intake tube, filter box and engine cover.
Second, take the lower shroud.
Image
Third, unscrew the upper shroud from the radiator and move it as far back as possible.
Fourth, unscrew the electric fan from the radiator and unhook the wire on the left side of the upper shroud. Lift the fan from the radiator mount and carefully slide the fan to the right where there is more room. Then lift the fan off from the shroud.
Image

Next, you lift the upper shroud off the engine bay. There you go, all the space needed to do the work.
Image

Next, you unbolt four bolts attaching the fan from the coupling.
Image

unbolt the four 10mm nuts holding the coupling/clutch from the pulley.
Image

here's the comparison of the old and the new.
Image

to re-install, just do it in reverse.
Image

:cheers:
Last edited by Cliff_Jumper on Wed Feb 16, 2011 7:26 pm, edited 1 time in total.


scrooks
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Postby scrooks » Fri Feb 18, 2011 11:22 am

Wow, Great write up and pics. What was the indication that the clutch was not working properly in your case?

Cliff_Jumper
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Postby Cliff_Jumper » Sat Feb 19, 2011 12:14 pm

The dealer said so and it was loud at start up. With this write-up, you can do a radiator replacement.

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disallow
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Postby disallow » Sat Feb 19, 2011 8:09 pm

Cliff_Jumper wrote:The dealer said so and it was loud at start up. With this write-up, you can do a radiator replacement.
great writeup man.

goblue90
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Re: replacing fan clutch/coupling - How to's

Postby goblue90 » Sun Feb 20, 2011 6:39 pm

Cliff_Jumper wrote:Just replaced the fan clutch over the weekend and it is not that hard to do.

Here's a step-by-step how to so you can do-it yourself.
:cheers:
Wow, great write-up! Thanks Cliff Jumper!

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gkb62001
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Postby gkb62001 » Wed Feb 23, 2011 2:09 pm

I guess it's still a little ambiguous to me how you detect if it's faulty. I'll check for fluid and to see if it feels loose, as well as trying to judge whether it spins too much or too little... My Pathy is very loud (sounds like the fan is very loud) sometimes, usually at startup or lower speeds and was particularly the case while I was in the mountains over the weekend. Now I'm worried that this may be an issue rather than just a normal function of the vehicle.

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disallow
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Postby disallow » Wed Feb 23, 2011 2:53 pm

gkb62001 wrote:I guess it's still a little ambiguous to me how you detect if it's faulty. I'll check for fluid and to see if it feels loose, as well as trying to judge whether it spins too much or too little... My Pathy is very loud (sounds like the fan is very loud) sometimes, usually at startup or lower speeds and was particularly the case while I was in the mountains over the weekend. Now I'm worried that this may be an issue rather than just a normal function of the vehicle.
I don't know what the spec on the Pathy fan clutch is. However, on the fan clutches that I buy for our coaches, they are called '2-speed'. The 2 speeds are 'slip' and 'direct'. Slip mode means the clutch is not locked, but the fan will still spin because there are magnets in the hub and the flange of the clutch that cause the fan to spin even though the clutch is not locked.

Once the Engine coolant Temp reaches the threshold (determined by the ECM), the clutch would lock and run in 'direct' mode.

If the Pathy clutch operates in a similar manner, a way to test the clutch could be to see if the fan can be stopped when you know the threshold for clutch lock has not been met. Could be dangerous. There must be a test to see whether the clutch actuator is working or not.


***EDIT***

After further research, I have found that the pathy fan clutch is a viscous fan clutch. There is a silicone fluid that changes properties as the ambient temperature increases, causing the clutch to engage. As viscous clutches age, this fluid becomes 'stiff' and causes the clutch to engage at lower temperatures. Eventually, it just stays on all the time, like on my truck.

Hope that clarifies. I wish it was an electromagnetic clutch like we use on the coaches that my company makes. Much more reliable and efficient.
Last edited by disallow on Wed Jun 05, 2013 5:45 am, edited 1 time in total.

valenburg
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Location: Maine

Postby valenburg » Sat Jul 09, 2011 5:42 am

My Path sounds like damn super powered box fan when I start it up, even in the winter. When rolling around town it seems a bit loud but I figured it was kinda designed to not run hot...I guess I will have to check it out. Would something like this effect fuel economy?

jpar
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Postby jpar » Sat Jul 09, 2011 1:18 pm

I tracked down a loud kind of rattling noise to this area, I thought it was the clutch too. I started the truck cold and jammed a srew driver into the fan blades to stop it from spinning, the noise continued. Then I used a long screwdriver as a stethoscope and can hear the same noise coming from the the fan pulley bracket behind the fan, I think the bearings going. Gonna order one up this week and see what happens.

Great write-up, I never think to take pics when I do stuff.

http://www.courtesyparts.com/21052m-bra ... 6855_6858&

twinblown
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Postby twinblown » Tue Jul 19, 2011 9:52 am

Is it necessary to remove the botom plate and lower shroud? couldn't this be done by just removing the upper shroud? or does the upper shroud not come out unless the botom is removed. I guess I have not looked in the engine bay to determine this. :?:

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gilldawg79
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Postby gilldawg79 » Thu Jul 21, 2011 7:29 pm

Would this noise you are referring t kinda sound like a roaring noise that follows acceleration? As in, when you rev it up it gets louder?

TheRealDoug
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Postby TheRealDoug » Wed Aug 24, 2011 6:59 pm

gilldawg79 wrote:Would this noise you are referring t kinda sound like a roaring noise that follows acceleration? As in, when you rev it up it gets louder?
I have a similar noise. To me it sounds like a fan, but am worried it might be timing chain....

Are electric fans available for these vehicles?

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JAHBLESSINGS
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Postby JAHBLESSINGS » Tue Sep 13, 2011 8:18 pm

Just recently changed my fan clutch also. I did mine with just removing the intake tube and loosing the two top shroud bolts. I then push the shroud enough to get my hands to reach the bolts. Took me about 20 minutes. Advice to pathy owners. beware of aftermarket clutch fans as I bought one and it was loud as hell I ended up returning it and got a oem one. The noise was unbearable.

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disallow
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Postby disallow » Thu Sep 15, 2011 7:30 am

JAHBLESSINGS wrote:Just recently changed my fan clutch also. I did mine with just removing the intake tube and loosing the two top shroud bolts. I then push the shroud enough to get my hands to reach the bolts. Took me about 20 minutes. Advice to pathy owners. beware of aftermarket clutch fans as I bought one and it was loud as hell I ended up returning it and got a oem one. The noise was unbearable.
Noisy in what way? Did it create interference with your fan shroud? Or was it spinning faster than the OEM one?

t

FMoreno1
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Avoid Non-Nissan Fan Clutches

Postby FMoreno1 » Thu Sep 22, 2011 8:37 am

Had a problem with my 2006 Pathfinder 4.0 L Fan Clutch. Initially installed a non-factory replacement clutch and had problems. Non-factory clutch shaft that was harder to turn and when installed the fan clutch was constantly engaged and loaded down the engine. This additional load caused the engine to rev higher especially when accelerating and also caused serpentine belt squealing and you had to press down on the accelerator more to get the vehicle moving.

Genuine Nissan clutch fixed the problem.


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