Fan clutch frustrations

SparkandFire

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So, the black truck has a new Motorcraft fan clutch, and the blue truck has an aftermarket fan clutch (judging by the part numbers on the housing.) Neither one of them work worth a damn. On the blue truck I clearly got the engine WAY hotter than I wanted to judging by my lower than normal oil pressure and the temp gauge all the way up to the "A" in NORMAL.

The other day I was pushing the black truck pretty hard up the hill and it's temp gauge got pretty high as well. I pulled over to make sure I still had water, all the hoses were pressured up, no leaks anywhere, the bottom hose was still round and not collapsed. But the fan was pinwheeling, and the bottom of the radiator was pretty hot.

I know some have had experience with the MS Tech fan clutch, but what are our other options? I would be willing to pin the thing down on the blue truck for extra cooling. I just hate to go drop a couple hundred bucks on a replacement clutch if it still allows the engine to get up into unsafe territory.

Also, both clutches look good, no ****** leaking out anywhere. Has anyone tried to pull the bimetallic spring out and shorten it before?
 

FORDF250HDXLT

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not considering the electric conversion hey?
if this is the '94 truck.you'd be surprised how easy the dual windstar fan assembly fits.direct drill/screw/nut bolt on 3 corners.only one custom fab corner (and that's easy) and she's all in.perhaps a bit grinding of the shroud to help clear,or install upside down for more room.takes 2 hrs max with 2 guys.instant cooling whenever you want it.
no power loss felt when on,and better economy.
 

OLDBULL8

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Without a real temp guage, you don't know how hot it got. The clutch don't kick in until about 230*.
 

icanfixall

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I think maybe Russ has some info on modifying the bimetal spring.. Hell.. Thats what MS Tech does. They claim there modified clutch comes in around 210 compared to possibly 240 for the factory oem ones. I know my Ms can reduce colant temps when I'm pulling the two diffrant grades out of so ca.. It sure looks and sounds odd to hear the b17 fan blades cutting the air and seeing the temps going down as your climbing... What a hoot....
 

typ4

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and I still have heating issues with the spring moved. Next big trip I am making a flat strap to go from pulley to fan, that will tell me what I need to know.
 

icanfixall

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Russ... Ever given much thought to removeing the heads and takeing out the closed off coolant ports in the block and heads... I know its plenty of hard ass work but why are these 4 passages closed off in our engines but open in the 6.9 engines...:dunnocookoo Its never mad good sence to close off coolant passages in an engine... Unless it was for better fuel mileage because the engine ran warmer or because the epa said the engine ran too dirty. So the craptacular engineers found out closeing off those ports heated up the engine enough that the fuel burned more... I don't know but its weird as hell to me. Pulling the heads.. Installing the 6.9 head gaskets on a 7.3 will work fine. I have measured the 6.9 and 7.3 head gaskets and they are demensionally the same every place but the lower head to block corner coolant ports.
 

gatorman21218

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Russ... Ever given much thought to removeing the heads and takeing out the closed off coolant ports in the block and heads... I know its plenty of hard ass work but why are these 4 passages closed off in our engines but open in the 6.9 engines...:dunnocookoo Its never mad good sence to close off coolant passages in an engine... Unless it was for better fuel mileage because the engine ran warmer or because the epa said the engine ran too dirty. So the craptacular engineers found out closeing off those ports heated up the engine enough that the fuel burned more... I don't know but its weird as hell to me. Pulling the heads.. Installing the 6.9 head gaskets on a 7.3 will work fine. I have measured the 6.9 and 7.3 head gaskets and they are demensionally the same every place but the lower head to block corner coolant ports.

If I ever get my parts;Poke;Poke:angel: I will do this on my truck. I plan on just punching out the 7.3 gaskets since I already have them.
 

typ4

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the springs are being sent direct from my supplier, the rest goes in tomorrows mail. I will check on the cam.should be on the way.
 

gatorman21218

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the springs are being sent direct from my supplier, the rest goes in tomorrows mail. I will check on the cam.should be on the way.

thanks russ I was just messing around. I know you are busy and have a lot going on.

As far as the plugs what is the best way to remove them?
 

icanfixall

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Do not just punch out the 7.3 head gaskets. That will not work correctly. The 6.9 head gaskets have a special orfice plate in this location. I may be able to post up some comparison pictures. But whatever you do... Do not punch out the 7.3 head gaskets.
 

Black dawg

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So, the black truck has a new Motorcraft fan clutch, and the blue truck has an aftermarket fan clutch (judging by the part numbers on the housing.) Neither one of them work worth a damn. On the blue truck I clearly got the engine WAY hotter than I wanted to judging by my lower than normal oil pressure and the temp gauge all the way up to the "A" in NORMAL.

The other day I was pushing the black truck pretty hard up the hill and it's temp gauge got pretty high as well. I pulled over to make sure I still had water, all the hoses were pressured up, no leaks anywhere, the bottom hose was still round and not collapsed. But the fan was pinwheeling, and the bottom of the radiator was pretty hot.

I know some have had experience with the MS Tech fan clutch, but what are our other options? I would be willing to pin the thing down on the blue truck for extra cooling. I just hate to go drop a couple hundred bucks on a replacement clutch if it still allows the engine to get up into unsafe territory.

Also, both clutches look good, no ****** leaking out anywhere. Has anyone tried to pull the bimetallic spring out and shorten it before?

what kind of shape is your radiator? If it is too dirty, it wont get any heat to the clutch to engage it.
 

lbzbuick

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Russ... Ever given much thought to removeing the heads and takeing out the closed off coolant ports in the block and heads... I know its plenty of hard ass work but why are these 4 passages closed off in our engines but open in the 6.9 engines...:dunnocookoo Its never mad good sence to close off coolant passages in an engine... Unless it was for better fuel mileage because the engine ran warmer or because the epa said the engine ran too dirty. So the craptacular engineers found out closeing off those ports heated up the engine enough that the fuel burned more... I don't know but its weird as hell to me. Pulling the heads.. Installing the 6.9 head gaskets on a 7.3 will work fine. I have measured the 6.9 and 7.3 head gaskets and they are demensionally the same every place but the lower head to block corner coolant ports.

I have a 7.3 apart right now that im building. I would love to do this, so what do you think I need to do to make this happen?
 

RLDSL

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I used to think my MS tech fan clutch was the bees knees.... untill it took a crap on me in the middle of a family vacation while towing heavy :backoff. That's when I decided to go electric.
 

IDIDieselJohn

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I can't remember what company my new fan clutch is on my camper, but boy does it ever work!

I have a real temp gauge as well! It locks in at around 195-200, and unlocks at 190.

Flat land cruising, I run 180*

And i've never seen it go over 210* on the gauge, that's climbing hills at 25mph in 1st gear, at 8000+ft elevations in the rockies, or some long but not steep hills in 110* Arizona summer heat!
 

Kevin 007

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I have purchased a few Hayden clutches, due to the fact that my old ones were seized and the fan would not spin by hand anymore. They are pricey buggers but they seem to be OK, I have never got an idi hot enough to engage it though...I have pulled everything from tractors to horses but never quite reached 210, I just gear down and keep out of the skinny pedal as much as I can, and we have some mean ass hills around here like you wouldn't believe.

In the winter I run with no fan at all, easier on the water pump.
 

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