Overheating

[Dan77CJ7]

I had the same problem when my motor was fresh, all new everything on the cooling end. and still ran HOT HOT! So i ran 165 T-stat in the summer/slow trails and 185 now and runs little hotter (189ish) then i'd like, but getting better perfomance then the 165. i like a cool motor. Good luck.


























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[Dan77CJ7]

when i"m going 55 on the highway, thats a High RPM condition!!!! what do i doooooo?

 

[Lumpy Grits]

You have me worried LG

Remember my incorrect fan? Well, I just ordered one from Amazon that was a flex lite max 400rpm. It's the only one they had that was CCW rotation and I'm impatient to get one in there if I order from some other site. Should I be afraid?

Amazon.com: Flex-a-lite 5919 Gold Steel, Aluminum bladed 19" Reverse Rotation O.E. Replacement Fan: Automotive

Why not check to see if your buddy with the jeep junk yard has a fan?
I won't run a flex-lite--Like I said, the ones I have seen fail. Start crack'n at the blade's rivets.
Also-That fan you ordered has a max RPM of 4K. Our 6's 'red-line' at 4500rpm.
Also--My search on Flex-Lite's site came up with "0" for our Jeeps r'rotaion apps.
LG

 

[mtnwhlr]

I ran a Flex fan on a '68 Charger with a big block for many years with no problems. And it was raced on the weekends. And a DD.

 

[Barry2]

Had the same problem and went to a salvage yard and got an electric fan from a Grand Cherokee with the V8 engine, there was only one year they were used on the Grand. Unfortunately I don't remember the model year.
These are 2 speed fans and they move a lot of air, works good on my 74 CJ5 with a 350 engine and works very well with a 383 supercharged TJ that is my "Street Jeep". If somebody locates one at a salvage yard, post up the year of the grand.

 

[Lumpy Grits]

I ran a Flex fan on a '68 Charger with a big block for many years with no problems. And it was raced on the weekends. And a DD.

How long ago was this?
LG

 

[Techlight]

Why not check to see if your buddy with the jeep junk yard has a fan?
I won't run a flex-lite--Like I said, the ones I have seen fail. Start crack'n at the blade's rivets.
Also-That fan you ordered has a max RPM of 4K. Our 6's 'red-line' at 4500rpm.
Also--My search on Flex-Lite's site came up with "0" for our Jeeps r'rotaion apps.
LG

This is probably what I'm going to do now. My plan was to have it tore apart before the weekend and put back together by thursday so I was impatient to get it back on the road since it's tagged and legal now. But my schedule got crazy this week so it's still sitting in the driveway. Hopefully he has one, otherwise it'll be fingers crossed with the flex a lite.

I still need to work a few kinks out of it anyway, so it won't kill me to have it in the drive for another week

 

[mstar]

I don't believe 1 failure of a flex fan constitutes that they are all bad.
I had a stock fan on my Dauntless Buick 225 V6 V6 fail from fatigue and sent the loose blade thru the lower rad. outlet.Could have been worse.Not all stock metal
fans are going to fail.Not really much of a issue with the advent of electric fans which I think would be the best choice for all cooling duty. I seem to have one of each,'69 Dauntless Buick 225 V6 flex-lite,'67 Dauntless Buick 225 V6 stock steel,'66 ford 427 side-oiler dual Spal electric. The OP's original question was a no brainer.The fans main funtion is to cool the engine at stand still and lower speeds.The fan is a drag on power after about 25 mph.That is the great thing about thermostat controlled electric fans , no waste.BTW it does little good to leave that fan running after engine shuts down unless you happen to have a electric coolant pump. my 2 cents. mike

 

[Lumpy Grits]

1 failure=NO. I never said it was just one
I have seen several fail over the decades that I have been in 'Jeeping'.....
I stand by what I said-I, for one will not run those fans. Everyone is free to choose-
LG

 

[Hedgehog]

This fan thing always makes me wonder about the real why of it. How many guys have we all seen that have run the factory fan/clutch/ fan shroud for 100,000 miles and at the very first sign of a heating problem stick on an electric fan or start stripping off things like the factory fan/clutch/ fan shroud for something after market like a flex fan. So what changed, what made the factory arrangenment suddenly worthless. In most instances the 100,000 Jeep needs a little cooling system care along the lines of rodding the radiator, a real engine flushing and a new fan clutch.

 

[Lumpy Grits]

H'Hog you are 110% 'rite'.
I just rodded out my radiator this pass winter. Not bad since it was 10 yrs ago I did it last. Resoldered, and will hold 25 psi all day.
Still-Even using distilled water w/coolant, there was some deposits that really took some poke'n to break loose in the passages. The 'tanks' weren't bad.
The block looked good. Still, I flushed it anyhoo. New 195* t'stat and rad cap.
I run the OEM fan, fan clutch and SHROUD.
Never have had any over heating issues, even at Furnace Creek at 115* air temp.
LG

 

[Techlight]

Just as an update...I ended up using the flex a lite fan. But it's not a flex fan. I was confused about that and someone ended up explaining it to me. The fan is an OE replacement and looks/feels exactly like my original fan (assuming the original is stock of course). It has more rivets per blade then the original as well and I'm assuming it's high quality since it's made in the U.S. It is a six blade instead of my 7 blade HD cooling fan, but that's the only difference except for the nasty gold color (if it ever comes off again I'm going to paint it). It cools the Jeep fine so thats good...it's running right where it should temp wise.

The 4k max gives me some pause but it we'll see how it holds up. I really don't get on my Jeep at all. And I surely won't be redlining it for extended periods of time lol.

I'll be the guinea pig on this one and see how it goes

 

[Lumpy Grits]

Best of news
The failures I have seen were all with the flex blade style.
NOT the ridged blade type.
You should be able to sell that other fan with ease.
LG