Radiator fan question.
Guest
Posts: n/a
Radiator fan question.
Hey all, the fan on my truck came with a after market flex fan. The dai. of this fan is 18". What is the dia. of the factory fan. I have 1 1/2" space between the fan blade tip and the shroud. I was wanting to go to a 20" fan which would leave me with 1/2" spacing. Is this to tight of a margin to allow for the torque of the motor. My reason for this is the water temp climbes up to around 210'F from 180'F when I'm crusing down the highway at 60mph. It also climbes sitting in traffic but I know this is normal. But when I get moving again it takes an loooong time for the temp to drop. I'm thinking the fan isn't pulling enough air through the rad. I had the radiator leak fixed at my local rad shop and he said the radiator is in good shape with the cap off I can see it has good circulation, the thermostate is new (180'F)and so is the water pump. They were all fixed as they went bad one by one. I tried to answer any questions you all might ask. It doesn't overheat, I just want to try and help it run cooler. Sorry I got carried away.
Mark
Mark
Tuned
Joined: Apr 2001
Posts: 443
Likes: 1
From: Athens, AL
Radiator fan question.
just some personal experience....i put a flex fan on my truck, and it started running hotter....i put the fan on one winter, and when summer came, i thought i had a stuck thermostat, but removal of the thermostat didn't help any....so i assume it's the fan...oh yeah...i have a complete new cooling system too....
which could also point to the radiator, because i think it came out of a small-engine truck.....
which could also point to the radiator, because i think it came out of a small-engine truck.....
Cargo Master
Joined: Aug 2000
Posts: 2,931
Likes: 12
From: SW Michigan
Radiator fan question.
OleblueMark, I've never seen a 20 inch fan for sale. How far into the shroud are the fan blades on the current setup ? If the fan is too far back from the radiator you can lose some airflow. How many blades does the current fan have, and does the fan have a clutch on it ? DF
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Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
Radiator fan question.
Ol'Blue This is just an observation, but when this question comes up here, it is more often than not, with the 351M or/400 engine.
I don't recall any good fixes either. What have you guys done to remedy this problem?
You could have put 390 pistons and crank in that ol 360 and had a much better engine too. too bad :-(
John
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66F100s Rule
In the cool still quite of night you can hear chevies rusting away.
I don't recall any good fixes either. What have you guys done to remedy this problem?
You could have put 390 pistons and crank in that ol 360 and had a much better engine too. too bad :-(
John
jowilker
[link:www.ford-trucks.net/users/jowilker|Club FTE since 01 01] My FTE Page
[link:www.ford-trucks.net/users/jowilker/NCFTE.html|NC Truck Owners] NC Ford Truck owners group
66F100s Rule
In the cool still quite of night you can hear chevies rusting away.
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Cargo Master
Joined: Jul 2000
Posts: 2,281
Likes: 18
From: Northern California
Radiator fan question.
Just a few suggestions:
get a high flow thermostat, they only cost about $9 from Jegs.com. Run 75% water and use WaterWetter or some ProBlend then 25% antifreeze. Check the timming, this has an effect on the temp and your 60mpg timming might be off. Bleed all the air from the cooling system, it can make a difference and some setups get air pockets in the head (usually with a low mounted rad, but still check for air pockets)
I got the factory A/C pullies and they spin the water pump faster than the non-A/C pullies, just something to think about. And if all that fails, a 4 core rad might be in order.
get a high flow thermostat, they only cost about $9 from Jegs.com. Run 75% water and use WaterWetter or some ProBlend then 25% antifreeze. Check the timming, this has an effect on the temp and your 60mpg timming might be off. Bleed all the air from the cooling system, it can make a difference and some setups get air pockets in the head (usually with a low mounted rad, but still check for air pockets)
I got the factory A/C pullies and they spin the water pump faster than the non-A/C pullies, just something to think about. And if all that fails, a 4 core rad might be in order.
Guest
Posts: n/a
Radiator fan question.
To everyone,the fan had a 3" spacer on it and I changed it to a 2" cause the fan blades where to far into the shroud plus a friend told me that if the fan spacer was to long the fan can wobble at higher rpm's. I guess I should put the 3" back on. I added a strip of plastic to the shroud cause the fan blades where about 1-2" from the shroud before changing fan spacers.I can trim the shroud to get the proper fan blade depth, good idea??? I bought the truck with this set-up. I would've loved if it still had the 360 in it, I don't know why he changed it instead of fixing it 
. The fan I bought from Jeg's it's the 6 bladed Perma Cool flex fan part #771-85180 with no clutch on it. Jeg's sells 20" fans #771-85200. One last thing I need to know is, how do you bleed the air off of the cooling system. This board is great, I don't know much about FORDS,(always owned PONTIACS) you guys are the best.
Thaks to everyone
Mark
. The fan I bought from Jeg's it's the 6 bladed Perma Cool flex fan part #771-85180 with no clutch on it. Jeg's sells 20" fans #771-85200. One last thing I need to know is, how do you bleed the air off of the cooling system. This board is great, I don't know much about FORDS,(always owned PONTIACS) you guys are the best.Thaks to everyone
Mark
Cargo Master
Joined: Aug 2000
Posts: 2,931
Likes: 12
From: SW Michigan
Radiator fan question.
OlblueMark, how about trying the 3 inch spacer and the 20 inch fan together ? If that is not enough, how about adding a A/C style water pump and pulleys as well. Let us know how you do. DF
Cargo Master
Joined: Jul 2000
Posts: 2,281
Likes: 18
From: Northern California
Radiator fan question.
If the rad sits higher than the engine, it usually will require simply warming up the engine so that the tstat opens then topping off the rad. Sometimes you can pump the top hose and get a few more bubbles out.
On a related note, the hoses should have wire inside them to keep them from caving in under suction, sometimes these wires will rust away and the hose can kink up or go flat and cause flow problems. Also a closed system with a recovery tank is best to keep the rad topped off, as the system expands some water tends to go out the hose and without a recovery tank the rad ends up no longer topped off. I've heard that being down 1/2" can cause 10 deg temp increase. You should be able to get a universal recovery tank for < $20 at most parts stores.
On a related note, the hoses should have wire inside them to keep them from caving in under suction, sometimes these wires will rust away and the hose can kink up or go flat and cause flow problems. Also a closed system with a recovery tank is best to keep the rad topped off, as the system expands some water tends to go out the hose and without a recovery tank the rad ends up no longer topped off. I've heard that being down 1/2" can cause 10 deg temp increase. You should be able to get a universal recovery tank for < $20 at most parts stores.