[TheRepairMan]

I found that mine was cracking also, when I removed it. I'm not sure if they eventually hand grenade or not, but yeah, I don't see why those fans wouldn't work just fine on your truck. I'll bet it's been done before.

That stock temperature sensor isn't designed to run fans through. They draw too much current for one thing. Don't do that ! Do take your time to do this right! Any electric fan, or fans need to be run on a 20 Amp fused circuit, through a fairly heavy 30 to 40 Amp relay, and then you are still going to need to add a controller. I'm just not sure of using the stock sensor, or switch you are talking about. That doesn't sound right to me right now.

They do make one even simpler to wire up than the one I used. And, actually you "can" run your fan power straight from the battery, on a fused wire, and the ground circuit through the thermostat below. It's got some pretty heavy contacts in it. I've done that on other vehicles, and it works fine, and is still adjustable.

Or this...
http://www.jegs.com/i/JEGS-Performance-Products/555/52125/10002/-1

It doesn't really say what Amp rating these controllers will carry. I'll recommend controlling a fan relay in line to ease the load and make the controller last.

-R

 

[jp2code]

Actually, I was thinking about this part of the D21 Service Manual:

My guess is the connector that goes to the Maxima's electric fan takes

1. Power,
2. Ground,
3. Temperature Signal, and
4. A/C On/Off signal (maybe)

If so, #1 and #2 are simple, #4 could likely be eliminated. So, that just leaves item #3.

Anyone know what section of the 2009 Maxima Service Manual would have similar coolant temperature sensor information? I'd like to know what temperatures its sensors are looking for. I might be able to add resistance to my connection to match the Maxima fan's requirements.

 

[jp2code]

OK, I found this in the 2009 Maxima Service Manual, in the EC section:

Hmmmm... I'm wondering how I can tell the fan to turn ON and OFF with this Engine Speed, Refrigerant Pressure, and A/C operation inputs...

Gotta think about this one.

 

[TheRepairMan]

Let us know how that turns out, jp2code. In my humble opinion you are attempting to do more than necessary to make this happen... too complicated, not to mention starting at spending $140 for the dual fan assy. The second problem I see is those fans would eliminate using the stock fan shroud. Not a good idea.

Never the less, it is an option for those with whom money is no object, and who wish to keep some type of OEM Nissan fans employed.
-R

 

[jp2code]

I appreciate your opinions, R. I haven't purchased the Maxima fan, so my options are still very fluid.

Case in Point: I've recently discovered the early Nissan Frontier trucks had an electric fan option. A Nissan Frontier electric fan is much less (LINK) than that Maxima version, would be more likely to bolt in with no modifications, and the connectors might even match up to the Hardbody's electronics.

I like that idea a lot more.

The fan by Skip White certainly looks capable (awesome website, too), and is likely more than a Hardbody would ever need; however, I have had bad luck in the past with those "sandwiched in" temperature sensors. I would rather find some way to tap into wiring and sensors that already exist on the truck instead of trusting my luck that my modifications would remain in place for 100k miles.

 

[TheRepairMan]

Yeah, that fan might work just as well. I'm not sure there is any way to use the existing D21 systems to trigger an electric fan, though. The temperature sensors on our trucks for the gauge and for the fuel system are "variable resistance sensors" just as your first diagram suggests, that don't have a set of contacts that ever close, as a temperature "switch" would.

There would have to be a dedicated "temperature switch" for the cooling system that would close at a certain temperature to ground the solenoid side of a fan relay, and go open as the engine cooled down. That's the old way cars do it, but now days all is sensed and switched through the Engine Control Units and they don't need an on/off temp switch. Our trucks just don't have that capability, not that I'm aware of. So basically we are talking about the difference between a sensor and a switch. They can look identical, but work VERY differently.

I think you are doing the right thing by researching this whole thing out thoroughly before you commit. I'll try to assist any way I can.
-R

 

[TheRepairMan]

Well, I said I'd report back here if any kind of a problem came up, so...

This whole thing has worked perfectly until lately during one of our coldest mornings of the Winter season. I noticed immediately upon start up one morning that the electric fan was running. Odd! I know that's not right... there's no A/C on, and no reason for it to be running on a dead cold, 17*F engine. That completely defeats the goal towards its best engine efficiency.

So, I have driven it to work a few times just to monitor what's going on. Seems that as the truck and everything under the hood finally warms up that the controller reverts back to working normally, at least it did for a few days, but now it has the fan going all the time, non stop. That won't do at all. Some cool days I've just pulled the fuse and run it with no fan, all the time closely watching the temperature gauge. Luckily, I haven't had to stop and put the fuse back in. The engine stays in the normal range with the gauge only going even near half way when at long stop lights.

Long story short. I got a hold of a defective controller. After researching some reviews, it looks like I'm not the only one. This "Imperial" brand sold at Advance Auto Parts has a history of failing, so I'll be replacing mine with a newer design from Derale. I have used theirs before with no problems at all.

I'll keep updating this thread as I get this done. It sucks, but parts do fail sometimes. Maybe more often these days than they should. Probably because "we" try to spend as little as we can on parts. The cheapest often isn't the best route to go, as this has proven.

Stay tuned!

-R

 

[TheRepairMan]

Advance Auto Parts agreed to warranty the Imperial controller for me, so I swapped it out yesterday. I'll admit that that was a pain... more or less, inconvenience to have to change it out, but it just meant taking the old one off and laying the new one beside it to cut all the wires to the same lengths, and crimp new connectors on in a couple of places. Not hard, just time consuming.

But, anyway, the replacement Imperial brand controller works just fine for now, and if this one should fail I'll go back to plan B and install another brand. Overall, I'm still glad I made the full fan swap. The weather here is slowly warming up now, so I'll do a hot day report soon.

-Roger

 

[TheRepairMan]

Just a quick update. The cooling fan and controller were put to the test pretty well today. Ambient temps out got up to 82* and I was in traffic stop and go for about twenty minutes and another twenty on the road. It's not really hot outside yet, so I'll be watching it and reporting what I see.

All's well so far... the engine is keeping its cool nicely. The temp gauge is staying below the half way point even with the AC on some.

-Roger

 

[cbrer]

Electric fan mod.

Outstanding project, and a quality install. I plan on performing this mod. to my 1995 hardbody with the 3.0 V6. Would you happen to know if the pulley clearance is the same for both models?

:newbie: Thanks! Brian

 

[TheRepairMan]

Outstanding project, and a quality install. I plan on performing this mod. to my 1995 hardbody with the 3.0 V6. Would you happen to know if the pulley clearance is the same for both models?

:newbie: Thanks! Brian

No, Brian, I don't know. I didn't even know what it was going to end up on my 4cyl until I did some trial and error mock up. I always had the last option of mounting the fan directly to the radiator cores, but that is a little risky with the vibration and stress added to an old radiator. I didn't want to take that chance, so I made the shroud mount work with just a little room to spare.

You can do some pretty close measurements between your radiator and the mechanical fan hub, and compare that to the overall height of the cooling fan you are going to use, then calculate just enough room attach the fan to your shroud and come up with shims or washers under the bolts to move the fan closer or further away from your radiator. Mine's pretty darn close, but doesn't touch when running, and that's what counts.

I've seen several street rods running these fans and they have almost no room left at all between the fan and the other components. I guess you do whatever it takes to make it work. Some run pusher fans, but there isn't any room for that on our trucks unless you don't have A/C. You might get two 6" or 8" fans up front, but I'm not sure they would move enough air.

-R

 

[TheRepairMan]

81* here today in stop and go traffic for about 30 minutes, and at a bunch of red lights, it all cooled very well. I even ran the AC some and as the compressor cycled on and off normally, so did the new fan. Engine temps never got quite up to the halfway point on the gauge so it's doing exactly what it's suppose to do so far. It's not really HOT out yet, so more testing to come.

Keep in mind, I never had any cooling problems with this truck. The idea behind the electric fan was to reduce the dynamic load or drag from the old mechanical fan. Turned out my old fan was getting lots of cracks in it anyway and was in danger of coming apart.

I'm trying to schedule a time to take the truck out of service long enough to do the timing chain and rails. Maybe the first week of July.

-Roger

 

[jp2code]

How did your summer go? Did the fan survive?

 

[TheRepairMan]

How did your summer go? Did the fan survive?

Oh yeah... it went very well. I didn't put a ton of miles on the truck last year. Probably just over 5,000, but the fan, controller, and installation gave me no problems at all in 2013. Even on the very hottest days we had (mid 90's), in traffic, with the AC on, the gauge never climbed over the half way mark. Most days, the fan hardly ever cycled at all, and the gauge would run at about one third. That seems to be normal on my truck with the factory thermostat in it.

I couldn't answer my own question as to whether it gave me any better return in fuel mileage, but I don't see how it could not help since it's no longer spinning a mechanical fan at any time. I absolutely would do this modification again if I had it to do over, but still I caution that this wasn't done to correct any sort of overheating situation. It isn't designed to make the engine run cooler than stock, just more efficiently... less constant mechanical load. When the fan does come on it draws a load on the battery and alternator, so is it a wash energy wise? I don't know, but I feel real good about the overall system operation.

So, after the initial glitch with my first controller being defective, once I replaced it in 2012 the new system has worked just as well as I hoped it would.

-Roger

 

[jp2code]

That sounds awesome.

I picked up a dual fan from an old Altima that I was going to wire up, but the temperature started rising really fast in the spring before I got it on.

Hearing your success really makes me want to try it again while the weather is still cool enough.

At one point in the summer, I found myself pulling much more of a load than even the Heavy Duty D21 should be doing.

It was around that 100°F mark, and the water temperature got close to the HOT mark even with the fan clutch. I was really worried, and I remember thinking I was glad I didn't have to worry about the electric fan that day.

Poor little truck!

 

[Realred96]

Going to do this soon. Went to the local pick a part to do field research and I agree with Joe that the Maxima fan set up is the way to go. The fans and motors seem to be more "higher grade" than the Altima units. May just be my imagination.

Another issue I see is that you need to be able to have logic that cycles the fans when the A/C compressor is on. It is in the Maxima ECU logic but sadly lacking in the D21 or WD21 ECU. his logic will have to be a separate circuit than the engine coolant temp switch, and will have to play nice together.

This could get complicated but I am in no hurry so I welcome the challenge.

I hope I am not over thinking this.

Jim From Houston

 

[TheRepairMan]

Going to do this soon. Went to the local pick a part to do field research and I agree with Joe that the Maxima fan set up is the way to go. The fans and motors seem to be more "higher grade" than the Altima units. May just be my imagination.

Another issue I see is that you need to be able to have logic that cycles the fans when the A/C compressor is on. It is in the Maxima ECU logic but sadly lacking in the D21 or WD21 ECU. his logic will have to be a separate circuit than the engine coolant temp switch, and will have to play nice together.

This could get complicated but I am in no hurry so I welcome the challenge.

I hope I am not over thinking this.

Jim From Houston

Hey Jim,
I'm real happy with the fan control relay I used. Mainly because it's self contained with its own replaceable relay, plus a sealed temperature probe, automatic, fully adjustable, commonly obtainable at most parts stores, relatively inexpensive, and had very clear connection instructions. This is about the fifth vehicle I've used this type on, and they do a great job, IMO. Here's the third post in this thread.

http://www.nissanforums.com/hb-truck/172728-electric-cooling-fan-controller-done.html#post1360511

Take a closer look at how this wires up before you jump in with involving the ECU and engine temperature circuit.

(1) RED wire - fused, 25 Amp, to the Positive (+) terminal of the Battery.
(2) BLACK wire - to the Negative (-) terminal of the Battery.
(3) YELLOW wire - signal wire from ignition source, to the small gauge ORANGE wire of the blue
Check Lamp relay in main relay box, or any source that's hot with key turned to run only.
(4) ORANGE wire - to the (+) side of the cooling fan connector (switched power to fan).
25 Amp Breaker or a 25 Amp Fuse is also suggested here by the fan manufacturer to protect
the controller system in case the fan were to short circuit.
(5) BLUE wire - not used, but can power up a second fan if needed.
(6) GREEN wire - signal wire from A/C power source, to the red and black wire in the single, light
blue A/C relay's wiring harness, or hot only when the A/C compressor clutch is engaged.

Keep us posted!

-Roger

 

[Realred96]

You have the better solution. I did not catch the part about the A/C relay circuit (6) on that controller.

No brainer to use that controller, especially since you have already proven it out.

Will definitely keep posting status as it happens.

Jim

 

[TheRepairMan]

You have the better solution. I did not catch the part about the A/C relay circuit (6) on that controller.

No brainer to use that controller, especially since you have already proven it out.

Will definitely keep posting status as it happens.

Jim

That said, I did have one develop a problem. As I recall, after about a month it started running the fan shortly after start up on a cold engine. At least it didn't fail the other way and not turn the fan on at all. The store exchanged it with another, and I haven't had any more trouble. The system was a real trooper all through last summer, and unless I sit and idle a long time somewhere it hardly ever has to run the fan during the cooler seasons.

It's always an option to run a manually operated toggle switch as a backup just in case the controller were to malfunction, but that kind of defeats the whole idea of an "automatic" temperature fan control.

I also see that the original link to the fan controller I used is no longer working. I find one and fix that link.

Once again, here's the controller I used... http://derale.com/products/electric...fan-clutch2013-10-18-11-52-51928758585-detail

And the installation instructions per Derale... http://derale.com/images/stories/virtuemart/product/pdfs/16759.pdf



-Roger

 

[CMax03]

I know it's 2 yrs old! You fell any extra Horsepower since the mechanical fan in't always on?