Cooling Fan On FJ62

[Bowling4$]

Can anyone shed some light on the "carb" cooling fan on the 62. I have never heard mine turn on. I can power it up by jumping it with a wire to the battery but other than that it never turns on. Oubviously the 62 doesnt have a carb but its there for a reason, right?

 

[willflow]

It is supposed to cool off the manifold and injectors. There is a sensor somewhere to turn it on. Try to find that and jump those wires.

 

[Elbert]

Yea....there is a sensore at the rear of the engine....through design failure the wire leading to the sensor is known to get damaged or destroyed by heat. There is a way to setup the fan where it will run every time you shut the truck off for a few min but some people dont like that, you'll have to search through the threads to find that as I don't recall exactly the way in which to do that.

Most likely the wire that connects to the sensor has been damaged and that is why your fan is not working. I believe the fan is there to help prevent vapor lock. There are a number of threads about it. You probally will notice a damaged wire hanging down on the rear of your drivers side fender well, and if you will look around (pics on other threads) you will see a sensor at the rear of the engine with the other part of the damage wire or it too may be damaged.

 

[MBcruiser]

Is the carb cooling fan supposed to come on while driving? When I drove my "new" fj62 home last week I kept hearing what sounded like a fan running periodically on the freeway. Any thoughts?

 

[klinetime574]

x2 on the wire being shot like Elbert said. Very common.

Is the carb cooling fan supposed to come on while driving? When I drove my "new" fj62 home last week I kept hearing what sounded like a fan running periodically on the freeway. Any thoughts?

Cooling fan should only operate after engine is shut off to my knowledge.

Another option: On the freeway your fan clutch could have just been locking up. The fan would be loud. Just due to the fact it is pulling lots of air when spinning over 2000rpm. HTH

 

[bentonrover]

x2 above. Mine comes on after a hard drive or hot day every so often after truck is shut down. Cool feature in my opinion

 

[Bowling4$]

Thanks for the quick responses! I definitely have never seen nor heard mine turn on so it must be the wire or the sensor. I'll check tonight and maybe search for the picture on the other threads. I know where the sensor and wire is just can't validate its condition.

 

[MBcruiser]

Thanks for the quick responses! I definitely have never seen nor heard mine turn on so it must be the wire or the sensor. I'll check tonight and maybe search for the picture on the other threads. I know where the sensor and wire is just can't validate its condition.

I guess I'll need to check mine as I have yet to hear it turn on after shutting down the engine. Is this a fix that needs to be done asap?

 

[MBcruiser]

x2 on the wire being shot like Elbert said. Very common.


Cooling fan should only operate after engine is shut off to my knowledge.

Another option: On the freeway your fan clutch could have just been locking up. The fan would be loud. Just due to the fact it is pulling lots of air when spinning over 2000rpm. HTH

Not to hijack the thread but could you elaborate for me to better understand what you are saying about the fan clutch. Thanks in advance.

 

[klinetime574]

Not to hijack the thread but could you elaborate for me to better understand what you are saying about the fan clutch. Thanks in advance.

The fan clutch is filled with a special oil. Once it reaches a certain temperature the clutch "locks up" letting the fan pull the most air it can. On old V8's and stuff they have no clutch. Always locked up. Our cruisers have clutches so that the fan can cool more when needed. Less when not needed. Hope that makes sense!

 

[MBcruiser]

Thank you for the fast response and explantion.

 

[Elbert]

a lot of trucks the fan just does not work. My truck has not been stock for some time, but when I first had it I did not know about the "carb cooling fan" and I never knew what it did. After reading the board a little bit I came across a thread about it and sure engough my wire was damaged. I forgot how this is done but I set mine up to come on every time after the truck was cut off and it would run for about 5 min or so, not using the factory sensor.

I believe the factory setup was based on the engine or exhaust manifold had to be so hot...then when the truck was cut off the fan would run for X number of minutes. The wiring and the sensor are the normal problems.. I don't think its that big of a deal with 62 with fuel injection....would be more important with the older carbed 60's.

Kind of a wierd setup but I guess that was "high-tech" somewhat back in the late 80's.

only suppose to run when ign off to the extent I know...i guess in part to deal with heat soak / vapor lock issues.

 

[robustbambi]

Mine comes on about a minute after I turn the truck off. Usually after a normal day drive

 

[Bowling4$]

So on initial inspection the wire looks to be in good shape. Got the Manual out and was going to test the relay when I found my multimeter is dead. I'll borrow one and begin testing.

 

[Elbert]

do some searching in the forum for "carb cooling fan"

 

[snowbound1975]

I had a similar problem a few months ago. I just grounded out the circuit from the sensor to the carb fan. Mine runs for 20 min after I shut the key off regardless of eng temp

 

[mrt6644]

I just looked at mine and I think the relay is missing.
Ive seen other posts where the relay is missing.
Does it make any sense that some of these 62's would be shipped without relays?
Is it hard to find these relays?
Why not just wire in another relay or another model relay?

 

[CarcaineProblems]

Just updating a few of these posts with pictures. Hope it helps those that are searching...

Here you can see the little bracket that the ground wire for the fan USE to be connected to:

I removed the wire and grounded it to the fender:

It now runs EVERY time I turn the motor off. I runs for close to 30 minutes IIRC

 

[ggmanning]

Anybody know what temp. the sensor is on the fan? Mine was shot so I rewired the lead and put in my own temp sensor. I picked to low because it comes on all the time after shut off unless it is very cold.