Thread: Fan keeps eating radiators

I tried those Falcon fans on the Oka with a Cummins 6BT and they worked ok up to about 25C ambient and then it all went west in a hurry. That was on the road, off road they just didn't cope at all.
The Falcon shroud like in a RRC needed minimal mods to fit the LT Oka and seemed to be a perfect fit to try.
I used a Davies Craig adjustable fan controller and the Falcon fans through relays and power sourced direct from the battery. Off road and slow going the fans ran continuously and engine temps were at the higher end of the standard range and they often ran for ages after engine shutdown which would result in seriously depleted batteries.
Using the aircon in over 25C created instant overheating so went back to the standard engine mounted fan which in an LT Oka is about 400mm behind the radiator at the end of a tunnel under the dash so no chance of it hitting anything.
At highway speeds the fan doesn't operate noticeably but slow down for a town or a long climb and it kicks in with a vengeance and its noise drown everything else out!

Thanks oka374, excellent information there and thanks for sharing. It is the very same sort of experience based feedback that I will be giving “warts n all” as they say. The fan I have is the 17.5 inch single (reputed 3700cfm) which was an upgrade on the earlier twin fans that are also used for these sort of retrofits. I was at the wrecker to get an early ZF autotrans sump pan with dipstick tube off a Range Rover and a little way down the row was a FG wagon that somebody had taken the radiator from and left the fan … hmmm that’d be an interesting side project and I’ll learn something along the way. $20 and it was mine.

Originally Posted by onebob

Okay - I’ll poke my head above the parapet and risk getting my head blown off and say that I too are modding a Ford Falcon FG fan to see how it would fit my new radiator. And before the naysayers interject, I’ve gotta say FFS these fans keep a supercharged 5.0L V8 cool so why wouldn’t it work for a 2.5L turbo diesel. I am going to find out ….

Don't forget most of the naysayers have been there and done that, I fitted twin EL Thermos to my D1 V8 once. I had them fitted for one day and pulled them out, they would run constantly in 30°weather and would struggle to keep the engine cool enough in slow traffic. Just my 2c, some things you just have to experience for yourself lol cheers

Originally Posted by LRJim

Don't forget most of the naysayers have been there and done that, I fitted twin EL Thermos to my D1 V8 once. I had them fitted for one day and pulled them out, they would run constantly in 30°weather and would struggle to keep the engine cool enough in slow traffic. Just my 2c, some things you just have to experience for yourself lol cheers

Yes I totally agree, and I will experience it - for better or for worse
What will it be?
When I get the D2 back together in the new year I’ll create a new topic about the fan install and report candidly on it’s efficiency or lack off…

Originally Posted by Slunnie

When I stop and then drive in, even with water well over the bonnet this doesn't seem to be a problem.

Likewaise, I stop and drive in slowly. I've had water so far up the bonnet it came inside the cabin. No problem with the radiator. I did find out that the air box leaks.

Originally Posted by Bohica

Likewaise, I stop and drive in slowly. I've had water so far up the bonnet it came inside the cabin. No problem with the radiator. I did find out that the air box leaks.

I’ve had it happen to me - the fan had a noticeable wobble, enough for it to be a problem when the fan touches water and the blades are pulled towards the radiator. The fix was a new fan assembly.

I am thinking that as you have stopped, the engine revs are lowish, the slow entry and slow increase in water level slows the fan down to a halt. There is not enough force from the water on the edges of the blades to pull the blades forward.

Originally Posted by Bohica

I am thinking that as you have stopped, the engine revs are lowish, the slow entry and slow increase in water level slows the fan down to a halt. There is not enough force from the water on the edges of the blades to pull the blades forward.

Yes! that would be best practise …. It didn’t help that my fan hub could wobble on the shaft - about 20mm measured at the tip of the blades - I was aware of the problem but ignored it