Outer Limits 4x4 Board

Hey There,
i'm thinking about junking the viscous fan thats fitted to my 93 2.5 swb auto Pajero and replacing it with an electric fan, as i've had to trim the original fan after lifting the body and i'm not happy that the smaller "trimmed" fan has enough spare capacaty for heavy off roading during hot weather and dont want to risk overheating the motor, has anyone else done this mod? (stupid question) and if so.

1. what size fan have you used
2. is it worth doing

i was thinking about using a 13 / 14 in fan or do i need to go even bigger, bearing in mind that in the uk we unfortunatly dont have very high tempratures even in summer prob a max of about 25/30C max (being bloody optomistic)

I don't know exactly why you actually had to trim the fan after the body lift ??
Usually after a 2" body lift (assumming that's what you did) only the bottom half of the radiator shroud needs to be removed for clearance.
This doesn't seem to effect the cooling in any way from my experience.
The later model fans are 8 bladed compared to the earlier 7 bladed units the outer profile is also wider to allow more airflow.
I would be looking to upgrade to an 8 bladed fan, replace the viscous coupling with a new unit and remove the bottom half of the radiator shroud so it will fit. Also check the rest of the cooling system for wear (radiator, hoses, thermostat etc) and replace if not confident.
You can also wire the 10" electric A/C fan to a dash switch to give you more airflow for slow offroad work in hotter conditions.
In Oz we have horrific hot conditions at times and long low speed speed hillclimbs really tests the cooling system out but in my experience the Mitsi's are fine as long as everything is in good working order.

i had to trim the fan as it was fouling on the bottom hose quite badly after a 2 1/2 in body lift, there is no problem for most of the time but i did notice that the temprature did start to rise a little up to 3/4 when i did particurly long (1/2 mile) and steep (35deg + on the gauge in the car)climb off road one which motor x bikes do seem to have dificulty completing again all at very lo speed on quite a warm day it was also at quite an altitude (for us) (2800 ft) so i think this may of had a bearing on it, but i have checked the entire cooling system and found it to be in good condition with no problems, and indeed the coolant is as clean now as it was when it was put into the motor, also i do prefere an electric cooling fan as it helps to warm up the motor more quickly and is better for deep wading as it dont spray everything with water and act like a big propeller (i know the viscous unit reduces this effect) not to mention being better for fuel economy and with fuel costing around £4.50 or $ 9.40 aus $ a gallon is a consideration too

Ok I assummed you did a 50mm body lift which still allows the bottom hose to clear the fan.
You can space the radiator down with some brackets and put everything back to stock and you shouldn't have any drama's as long as the cooling system is in good order.
I can say I had a NH with 50mm body lift and used the later 8 bladed fan with a new viscous coupling and had a 3 core radiator made up with the standard cowling after spacing the radiator down.
I also replaced everything else - water pump, thermostat, hoses, radiator cap etc and it worked very well.
It was only on very extreme long steep slow hillclimbs in very hot weather (40 deg plus) that the temp needle would start to creep up (would stay on between 1/4 to 1/3 all the time). I also wired the A/C fan to a dash switch for such situations and honestly only had to use it 3-4 times. I also installed another 10" thermo next to the A/C fan after stripping out the A/C and condenser making room. The second fan was wired to the same dash switch. I did experiment with using just the electric fans on their own for cooling by clamping the viscous fan and they weren't enough on their own.
I've seen electric fans cack themselves after numerous bogholes & river crossings as they are not inherently water proof.
Not a fan (pardon the pun) of these myself for serious 4wd's but fine for road cars.

the body lift that had beem done is just over 2 1/2 in at 65mm not a 50mm lift, so needed to trim the fan to clear the bottom hose if i had only done a 50 mm lift then there would have been plenty of space, also the rest of the cooling system is in 100% order and i have also checked to see if there is any chance that the head gasket may be on it's way and it is also without any problems whatsoever, i tried the ac fan and it works really well, so will be using this to suplement the main fan and simply dont want the added drag caused by a viscous fan and as for electric fans not being waterproof i have to disagree as the ac fan is electric and dont have any problems with water it just depends on wheather a suitable fan has been chosen for the job, the other reasons why i dont want to keep the viscous unit is as i have already mentioned
1. the added drag on the engine (decrease in performance - every little helps on a 2500 diesel)
2. increased engine warm up time
3. added fuel consumption compared to an electric unit
4. lack of control (temprature)
other than that i think viscous units are great, and that nearly all new vehices use an electric fan says that the old fasioned viscous units are not that good when compared to a SUITABLE electric unit and are most definately "old hat"
but do thank you for your opinion however i was looking for advise from people who have fitted an electric fan to a pajero, and not to debate the merits or otherwise of electric vs viscous units, but once again do thank you for you opinion

hi guys,
i am using a fan that is much bigger to your fan matt and i am satisfied to its blow of wind in using this i can have a less consume of energy of my car if i only the person in my car.,.this fan is worth it and i like it.,,.


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Fanimation Fans

i fitted a 16 inch electric fan and works great less load on the motor also.

I run electric fans on most everything I build. here is my 95 3.5 with an alloy radiator and electric fan setup.

Thanks very much for the picture that's most helpfull, my fan has arrived today so will be fitting it tomorrow (with luck) also the fan that i've got looks to be of a very similar pattern to yours.

This one is a relatively inexpensive fan, no brand name unit. I install fittings into a end tank of the radiator with a 16mm thread to install the thermo switch and wire them with a relay so the fan can run with the key off.

I have been considering this for a while too. Can the thermo switch be connected to the top housing instead where there sould be a point for it?

Also, this would eliminate all the noise from the stock fan as well shouldn't it? That's the noisiest part of the motor!

If you rely on a fan switch in the outlet the engine temperatures will not be stable since the water has to rise above the thermostat temperature to get the fan to cycle.

The fan will respond better if the switch senses the return water temp. This has the fan run only when the radiator can not do it's job with the natural airflow and keeps the engine temps more stable.
But there is no reason that the switch should not be mounted on or near the outlet. On most of Mitsu's cars during the mid 90s the fans primary control was either by the ECU or switches in the lower tank. But they also installed a higher temp switch in the water outlet as a failsafe.

And yes, the engine is much quieter with the electric fan.