NH 3lt V6 Thermo Fan setup

[GREGGO]

Hey, South. Here's some photo's and a "quick" story.

The instuctions you get from Davies Craig (http://www.daviescraig.com.au) are very good. With the instructions and a copy of a Gregorys type manual, it shouldn't be too much for most home mechanics.

First off the car is the original fan and clutch assembly. Loosen the 4 fan retaining bolts whilst there is tension on the fan pulley. Now loosen the serpintine belt adjuster. Remove the 4 retaining bolts and remove the fan assembly. In the case of the 3Lt V6, you should be able to refasten the pulley with the original bolts. It's a good idea to fit a spring and flat washer on each bolt to A, space the bolts out to near their original position (stops them from fouling on the water pump housing) and B, it stops the pulley falling off.

Next job is to drain the cooling system and remove the radiatior. Remove the fan shroud. Now is the time to carefully re-read your fitting instructions because if you puncture your radiatior, this will cost you a lot more. Depending on your existing radiatior core size, and physical room; you must now work out whether to fit your fans upstream or downstream. In my case I've already had a larger core fitted so I had to fit the fans on the downstream side. This meant removing the fan blade and flipping it over as per the instuction sheet. This makes sure that the fans pull air from the grille towards the engine bay. Line up the fans on your choice of side and work out the best position for the fans and their mounting clips. The fans are mounted directly to the radiator so make sure that the surface of both the fans and radiator are free from debris and sharp edges. Carefully use a round chainsaw file or No 1 Phillips screwdriver to "drill" through the fins of the radiator. Using the bolts and washers provided, fit up the fans. You might need to shorten the bolts. I wired up the fan wires with a 4 pin plug (not supplied, available from auto shop) so that if the radiator needs to be removed later, it only means the removal of one tidy plug, not 4 messy wires.

Next job was to find a mount for the thermal switch. I decided to use the more basic switch for two reasons. A, I've used it before with no problems, and B, the flash'o fully electric jobbie is over twice as expensive and probably won't like a lot of mud. The thermal switch comes with a mounting bracket that I straigtened then shortened and mounted to the LH top shoud mounting point. Removing the switch for extra room, refit the radiator and connect only the bottom hose. Remount the thermal switch and carefully fit the thermal pickup tube inside the top hose using the rubber support strip supplied. Take care to make sure that the end of the pickup won't chafe the hose and that the pickup is supported well and won't move about. Make sure that the remainder of the pick up hose is coiled up safely and cannot be damaged by chaffing or the like. Using a good quality RTV sealant, seal the radiator outlet tube, support strip, pickup tube and radiator hose together and refit and tension the hose clamp. Whilst the RTV sets, it's time to tackle the wiring.

Using the wiring diagram supplied, layout the supplied wiring and group the wiring of the two looms. Tape up the corresponding wires that go to the same place at regular intervals. As you can see from the photo's, I "zip" tied the relays to the bottom of the existing wiring loom, in front of the coolant over flow bottle. I also tied the fan fuses up high for easy access. Remove the fuses from their holders to prevent any shorts during hookup. Wire the red Main power lead to the main battery terminal. Connect the black earth leads to either the battery negative or a chassis earth. I used the support mount bracket for the a/c. It has a convienent stud for a clip to be mounted and a 6mm nut to retain it. Connect the blue and black fan wires. The thermal switch needs a power source (grey wire) that activates when the ignition is turned on. I used the power wire to the horns as it was convienient to locate and doesn't get used much. Make sure you pick the power wire or your fans will only try to work with the horn going. Connect the green relay activation wire to the thermal switch.

To test the wiring, refit the fuses and turn on the ignition. Turn the switch adjuster anti-clockwise untill a click is heard. The fans should both start up. Check that both the fans are drawing air from the grille and are "pushing" air towards the engine. If the fans do not start up, check your wiring, fuses and connectors for faults. I used professional crimping equiptment when fitting my system as it is easier to get a better connection than using std gear. Plus, the finish looks more "factory". If it all works fine, cover all wires with split tubing or something similar, to protect the wiring. Tie the wiring securely to the existing harness at regular intervals to reduce wire strain from vibration etc.

Now refill and bleed the cooling system as per workshop manual. The setting of the termal switch cut in temperature is covered well in the instruction sheet. Basically, start the engine and allow it to get to operating temp. Now run the engine above idle so as to get the engine to a temperature between normal highway running and "too hot". Adjust the switch from the fully anti-clockwise position to the point where the fans stop running. This should be approximately 5 to 10 degrees C above normal operating temp. This can be judged by keeping an eye on the temp gauge in the car. The fans need to be set to cut in above normal operating temp or they will cycle almost continously. As the engine runs at idle, the fans should cut in at regular intervals for a period of 30 to 60 seconds at a time. If they run for longer, turn the adjustment switch clockwise to increase the cut in temp. You may need to run the car for several days untill you get the fans "tuned" correctly.

I've probably missed out some thing but as I said earlier, the instructions that come with the product are good. This has made a noticable differance to the roll-on acceleration of my Paj and has gotten rid of the awful swooshing noise of the std fan continually running. Hope this helps someone out. Pics below!

[GREGGO]

Pics

[GREGGO]

more pics

[Tas_Dean]

Anyone contemplating this be aware, NO radiator manufacturer will gaurantee their product with fans mounted through the Radiator!

But great work with the instuctions! Thermos are great, especially if you put a bypass switch in to turn them off during watercrossings! But if you do that, you want to connect a big Red (or similar) light on the dashboard to let you know when you have them bypassed, just in case you forget to turn them back on!

[South]

Thanks Greggo for that. Its a bit late now to read it (the brain switched off hours ago), but tommorow morning I shall have a gander.

Cheers
South

[MKPatrolGuy]

Just one thing. Are Pajero horns switched with the ignition. I have never driven a Paj but every other car i have driven you could honk the horn without the ignition on.

[kanis]

Hi Greco

what types of vans did you use?

wolf

[Hekta]

Just one thing. Are Pajero horns switched with the ignition. I have never driven a Paj but every other car i have driven you could honk the horn without the ignition on.

Yeah. Key has to be turned to 'ON' to honk the horn.

[MKPatrolGuy]

Just one thing. Are Pajero horns switched with the ignition. I have never driven a Paj but every other car i have driven you could honk the horn without the ignition on.

Yeah. Key has to be turned to 'ON' to honk the horn.

How weird...

[GREGGO]

Hello Kanis,
I used two Davis Craig DCSL12 fans. Check the above link for vehicle application lists.

Greggo