Radiator protection from fan abuse

[Outsane]

I have seen a few radiators get eaten by fan blades. This is usually blamed on bad motor mounts. Somet I mes it happens on a jump or just a cow crossing.

Also seen several happen on 4wd247 show..

Well here is what I am doing about it...

The before

and after

I welded in a piece 1in wide peice of flat stock. Just welded the end and a few tacks. I didn't do a full weld on the tank side, ti make it easy to remove, and also so I dont make a hole. The top is about 1/8 away from the cooling tubes. I don't expect a significant loss in cooling from the rad. Less of an issue with diesel is my understanding. My biggest concern is that dirt will pile up. Maybe I should have left larger gaps on the bottom.

Thought I would share, I haven't seen this done before. I have an oem rad I may mock up a solution for also.

This is the 4row rad from Amazon that is made for a 1hdt, so the tab is moved over a little.

 

[Marco Lau]

I had 2 Ron Davis eaten up by my manual fan for the past 5 yrs and i had to agree one time is due to a bad tranny mount. The second time it happened, i had all brand new motor mounts and transmission mount installed prior to the incident and the fan took out my shroud, destroy the fan blades and chewed up my Ron Davis coming down to the bottom of Cadillac hills in the Rubicon, and had me stranded by Rubicon Springs for 2 days./ The real fix is to ditch the fan clutch and go with a complete elec. fans setup. I also found out the plastic blades tend to bend ever so slightly at the tip due to heavy oil replaced inside the clutch, added a tired engine/tranny mount and the aftermarket alum. radiators are thicker in depth than factory units all contributes to the above. The Elec. fans are worth the investment. Much better cooling on 4Lo rock crawling application, much better efficiency with AC on slow heavy traffic. I am super happy with my conversion and probably one of the better mods i have done to the rig for offroading.

 

[tmxmotorsports]

I had 2 Ron Davis eaten up by my manual fan for the past 5 yrs and i had to agree one time is due to a bad tranny mount. The second time it happened, i had all brand new motor mounts and transmission mount installed prior to the incident and the fan took out my shroud, destroy the fan blades and chewed up my Ron Davis coming down to the bottom of Cadillac hills in the Rubicon, and had me stranded by Rubicon Springs for 2 days./ The real fix is to ditch the fan clutch and go with a complete elec. fans setup. I also found out the plastic blades tend to bend ever so slightly at the tip due to heavy oil replaced inside the clutch, added a tired engine/tranny mount and the aftermarket alum. radiators are thicker in depth than factory units all contributes to the above. The Elec. fans are worth the investment. Much better cooling on 4Lo rock crawling application, much better efficiency with AC on slow heavy traffic. I am super happy with my conversion and probably one of the better mods i have done to the rig for offroading.

Because electric fans won't leave you stranded either and will never hit the radiator...

 

[Marco Lau]

Because electric fans won't leave you stranded either and will never hit the radiator...

I will agree with you that it will never hit the radiator, but i wont guaranteed it wont leave you stranded...lol

 

[tmxmotorsports]

I will agree with you that it will never hit the radiator, but i wont guaranteed it wont leave you stranded...lol

My statement was complete sarcasm on the electric fans

 

[Marco Lau]

My statement was complete sarcasm on the electric fans

I was hoping you won't go there twice, but you did anyways...

 

[Mark W]

Because electric fans won't leave you stranded either and will never hit the radiator...

Sorry, I am gonna have to disagree. I have personally seen two different electric fans fail. Both on the trail as it happened. In one case we were able to rob an aux electric off of a rig running it for extra cooling along with the absolutely dependable (and non-damaging potential having) factory CLUTCH fan and use that to keep the injured rig kinda sorta cool enough for the couple opf days back to the trail head and a trailer. In the other case we actually had a replacement fan flown out via a Supercub which landed it on a narrow ridge top strip for us about 70 miles from the trailhead. It was actually cheaper than what it would have cost to get a couple of rigs back to the trail head, back to town and then back to us... and a LOT quicker.
In another instance, it was not really a failure of the fan, but.... at low speeds (trail speeds) the stock alternator in a.... '76 IIRC FJ55 could not put out enough amperage to keep the voltage up and the electric fan (which was the only fan under the hood) was not turning fast enough to cool the engine. and in yet one more ocurrence... a dead alternator on the trail resulted in a rig that could not keep going for long with the fan running off the battery. If he had only had to power the ignition he cold have made it back to the trailhead, but with no real cooling (slow fan speed again) and before long a completely dead battery... nope.

Fortunately for him, a couple of us were running dual batteries and we were familiar with the routine... swap his battery out when it died, toss our secondary in it's place and recharge his in our rig(s) while he drained the fresh one and just rotate the duty around because we could. Kept him on the trail with us for a couple of days with only minor aggravation that way.

Anyway... an electric fan can indeed contribute to and actually be the cause of "stranded".


I AM on board with the concept of an electric fan not damaging the rad

I have seen OEM non-clutch fans damage radiators. I have actually seen GM clutch fans (mounted on swapped in V8s) damage radiators. I have seen the OEM clutch fan on a 3'4 V6 damage a radiator. Both of those clutch fans did the deed when they were suddenly dropped into deep-ish water while at high-ish rpms. (crawling big-ish rock in a creek crossing) They both flexed an impacted immediately before the clutch was overpowered and allowed slippage. Yep, even that heavy duty GM fan!

But... I have never seem an OEM Land Cruiser clutch fan impact a radiator except for in a collision or *maybe* when motor mounts are broken and the rig is still pushed down the trail.

I've run all the older rigs of course. Going back a bit over 40 years now. The past dozen or so years I have spend more and more time on the trail in one of my '80s and I have a several buddies who can say the same. As well as newer guys to the crew who started in '80s. Lots of highway and road miles. Smooth and rough (plenty of both in Alaska and western Canada after all). Lots and lots of trail miles. Again smoth and rough (in other words playing "off road rally boys" sometimes and "flex it all out" crawling occasionally along with all the easy miles). And lots and lots and LOTS of water crossings (not the few inch deep silliness either).
Anyway, the '80s get subjected to real trail use just like all the other rigs (and not just the ones on 38 inch Dick Cepecks and 40 inch Boggers).

If you want a dependable, NOT damage prone and virtually failure proof fan that move the most-est air... OEM clutch fan!

BTW... FOR THE OP!!!

That piece of flat stock that you bridged across the radiator will almost certainly do almost NOTHING to protect your radiator from a fan strike.


Mark...

 

[Outsane]

That strip is where I have personally seen two radiators get eaten by a fan. Also talked to others with the same problem.

So we have different experiences.

 

[jonheld]

I am in the process of replacing an OEM TRAD 16400-66040 in my LX450.
I was on a not so extreme trail and the fan sliced the radiator at the very bottom, a fraction above the seam for the lower tank. I'm still trying to figure out how this happened.
All 3 motor mounts were replaced with new OEM within the last few months. The old ones came out in 2 pieces.
While I was pulling things apart in my driveway, I put a floor jack under the motor and was looking for separation. Saw none. Removed both front motor mounts and inspected. Both looked brand new.

I run a 100% OEM setup, with the exception of a modified OEM fan clutch.
What gets me is that the fan lives behind the lower part of the shroud. I can't imagine the mechanics of how this could have happened.

Ordered a new radiator, mounting hardware, shroud, and fan, All OEM.
Replacing the water pump with a new OEM I had sitting on a shelf, swapping to another modified fan clutch.

 

[VPP]

Sorry, I am gonna have to disagree. I have personally seen two different electric fans fail. Both on the trail as it happened. In one case we were able to rob an aux electric off of a rig running it for extra cooling along with the absolutely dependable (and non-damaging potential having) factory CLUTCH fan and use that to keep the injured rig kinda sorta cool enough for the couple opf days back to the trail head and a trailer. In the other case we actually had a replacement fan flown out via a Supercub which landed it on a narrow ridge top strip for us about 70 miles from the trailhead. It was actually cheaper than what it would have cost to get a couple of rigs back to the trail head, back to town and then back to us... and a LOT quicker.
In another instance, it was not really a failure of the fan, but.... at low speeds (trail speeds) the stock alternator in a.... '76 IIRC FJ55 could not put out enough amperage to keep the voltage up and the electric fan (which was the only fan under the hood) was not turning fast enough to cool the engine. and in yet one more ocurrence... a dead alternator on the trail resulted in a rig that could not keep going for long with the fan running off the battery. If he had only had to power the ignition he cold have made it back to the trailhead, but with no real cooling (slow fan speed again) and before long a completely dead battery... nope.

Fortunately for him, a couple of us were running dual batteries and we were familiar with the routine... swap his battery out when it died, toss our secondary in it's place and recharge his in our rig(s) while he drained the fresh one and just rotate the duty around because we could. Kept him on the trail with us for a couple of days with only minor aggravation that way.

Anyway... an electric fan can indeed contribute to and actually be the cause of "stranded".


I AM on board with the concept of an electric fan not damaging the rad

I have seen OEM non-clutch fans damage radiators. I have actually seen GM clutch fans (mounted on swapped in V8s) damage radiators. I have seen the OEM clutch fan on a 3'4 V6 damage a radiator. Both of those clutch fans did the deed when they were suddenly dropped into deep-ish water while at high-ish rpms. (crawling big-ish rock in a creek crossing) They both flexed an impacted immediately before the clutch was overpowered and allowed slippage. Yep, even that heavy duty GM fan!

But... I have never seem an OEM Land Cruiser clutch fan impact a radiator except for in a collision or *maybe* when motor mounts are broken and the rig is still pushed down the trail.

I've run all the older rigs of course. Going back a bit over 40 years now. The past dozen or so years I have spend more and more time on the trail in one of my '80s and I have a several buddies who can say the same. As well as newer guys to the crew who started in '80s. Lots of highway and road miles. Smooth and rough (plenty of both in Alaska and western Canada after all). Lots and lots of trail miles. Again smoth and rough (in other words playing "off road rally boys" sometimes and "flex it all out" crawling occasionally along with all the easy miles). And lots and lots and LOTS of water crossings (not the few inch deep silliness either).
Anyway, the '80s get subjected to real trail use just like all the other rigs (and not just the ones on 38 inch Dick Cepecks and 40 inch Boggers).

If you want a dependable, NOT damage prone and virtually failure proof fan that move the most-est air... OEM clutch fan!

BTW... FOR THE OP!!!

That piece of flat stock that you bridged across the radiator will almost certainly do almost NOTHING to protect your radiator from a fan strike.


Mark...

It's the reason Military manuals of WW2 required the truck generator belt to be loosened prior to fording deep water - to prevent the fan blades from pulling into the radiator. Anybody running a belt fan should heed this procedure prior to deep water.

 

[Outsane]

@jonheld Maybe check the bushings that hold the rad in also. The frame does flex, some get chewed in a cow crossing taken aggressively.

 

[jonheld]

@jonheld Maybe check the bushings that hold the rad in also. The frame does flex, some get chewed in a cow crossing taken aggressively.

The rad I just pulled out was installed last April with all new OEM everything. That one was eroded at the very top by a hanging wire harness that had broken free and was chafing for quite a while.

 

[Outsane]

ah good stuff!

 

[mudgudgeon]

I also don't think one bar is going to prevent a chewed radiator. I think it's a false sense of security at best. At worst, it could give the fan something to grab, causing the blade to cone apart and chew the radiator when it may have just grazed it without the bar.
Or, vibrations cause the bar to chew a hole in the fins

You should set up a destructive test and video it to show us if your theory is good

Or, take other precautions, and worry about swapping out the radiator in the unlikely event it gets chewed. Doesn't happen often

Old school methods for water crossings are tie a tarp over the front of the hood and grill to create a ln air pocket to keep water out of the engine bay, fan, intake. Or, tie the fan with a piece of cord to stop it rotating while you do a water crossing.

 

[jonheld]

ah good stuff!

No, not really. But I am getting pretty good at swapping radiators.

 

[Outsane]

No, not really. But I am getting pretty good at swapping radiators.

I drilled a hole in the bottim of my driver's side battery tray to make it easier to remove a radiator.

 

[Outsane]

@mudgudgeon. They have also gotten chewed doing jumps, its not just water crossings. I will update the thread if there is any contact.

 

[Mark W]

That strip is where I have personally seen two radiators get eaten by a fan. Also talked to others with the same problem.

So we have different experiences.

Fair enough. Different experiences leads to different opinions.

The usual damage I have observed tends to be a circular pattern around the perimeter of the fan blades. If it is not a full-ish circle, the most usual impact area is the bottom left hand sector (6 oclock to 9 oclock) Looking at it from the engine side of the radiator of course.

Mark...

 

[Mark W]

Old school methods for water crossings are tie a tarp over the front of the hood and grill to create a ln air pocket to keep water out of the engine bay, fan, intake. Or, tie the fan with a piece of cord to stop it rotating while you do a water crossing.

Years ago I used to practice and advocate the tarp across the grill approach. But... when you wind up doing a few dozen crossings a day on one of the trails that are following a river to the glacier it comes out from under... in the river bed the whole way... installing and removing the tarp over and over just really is not feasible. And on longer duration slower deeper crossings, the water will come up behind the tarp from underneath, the sides or wherever it wants to anyway.

For some situations it IS a helpful approach. Just not all of them. But that can be said for an awful lot of the things we do to get where we want to be.

I don't do it myself any more but I absolutely see the benefit of the cord around the fan for a short crossing. (again, assuming you are not having to do it over and over all day).

Loosening the belt *can* kinda sorta make your old old school solid fixed fan act like it is a clutched fan. But if I was not in some sort of "get it done or die" situation, I would NOT want to bank on that working right every, or even in any specific case.


But... if we take all that we can learn from our experience and combine it with all that we can learn from others experiences... we can have an awful big box of "tools" pick and choose from for any given situation.


Mark...

 

[Mark W]

I drilled a hole in the bottim of my driver's side battery tray to make it easier to remove a radiator.

I LIKE that idea. Gonna copy it the next time I have the batteries out!.

Mark...