FE clutch fan installation: Hayden 2710 and Derale 17118.

[robroy]

Good day!

Does anybody know the specifications of the fan that my truck came with? What was its diameter?

As some of you know, #50's a 1972 F250 FE+T18 bare-bones model.

Here's a photo that shows the factory-style fan shroud I'm using (it's a reproduction from LMC): 2011Feb24_FESpecialties_C.JPG

I think this shroud's a super common type found on FE Bumpsides.

My reason for asking is this: the Derale P/N 17319 19" fan I'm using now is very loud (probably the noisiest thing on the whole truck), and I'm planning a thermostatic clutch fan setup to help reduce the noise. But the Derale fan I have now comes really close to the edges of the shroud--I had to clearance it slightly in one spot, in fact. So I'm hoping that this shroud's really meant to accept an 18" fan instead.

Thanks very much!
Robroy

[forrestbump]

Robroy,

Measured my O.E.M. 5 blade steel fan on the 390 FE in my Bump and it's 18" in diameter. It also fits within the O.E.M. fan shroud as well with about 1" of spacing between the fan and shroud (I'm assuming that's to allow for flexing of the engine and chassis).

Don't know if it matters, but my Bump has a super cooling radiator.

Hope this helps. I send y'all a picture, but NO cell phone or camera... deep sigh.

[fordman]

in my experience the clutch fans are noiser. and makes the truck sound like it is really winding out. that is what my dakota is doing to me right now. but i also on that ruck have the different fan shroud off of another year of truck. so that could be part of it. my 94 clutch fan doesnt make that roaring sound. but my 68 does. and it is the correct shroud. although i dont think it is the factory clutch fan. it may be. i don't really know for sure. good luck and i hope you get it taken care of.

[robroy]

Good afternoon Larry and Fordman, thanks for your superb replies!

Measured my O.E.M. 5 blade steel fan on the 390 FE in my Bump and it's 18" in diameter. It also fits within the O.E.M. fan shroud as well with about 1" of spacing between the fan and shroud (I'm assuming that's to allow for flexing of the engine and chassis).

Fantastic!!! Thanks very much for measuring that for me Larry. And I think you're right about the space being there to avoid clearance problems when the engine's fully flexed to one side.

In fact, that's how I discovered my clearance problem with the 19" fan! The first time I gave it a little gas I heard a weird "crack" sound, and I found a chip taken out of the inside diameter of the shroud hole when I got home. I was actually pretty lucky that the fan didn't just eat the shroud alive!

Don't know if it matters, but my Bump has a super cooling radiator.

OK! The shrouds are different, but the data point you've provided is useful nonetheless--thanks!!!

Hope this helps. I send y'all a picture, but NO cell phone or camera... deep sigh.

No problem! I know what you mean about the camera; it's a great tool for FORDification posts. I need to buy a new one also.

in my experience the clutch fans are noiser. and makes the truck sound like it is really winding out. that is what my dakota is doing to me right now. but i also on that ruck have the different fan shroud off of another year of truck. so that could be part of it.

Interesting--thanks Fordman. Do you think they're sometimes noisier simply because the fans they pick out for clutch fan arrangements are more aggressive (more blades at a steeper angle)? Do you think the clutch mechanism itself makes any noise?

my 94 clutch fan doesnt make that roaring sound. but my 68 does. and it is the correct shroud. although i dont think it is the factory clutch fan. it may be. i don't really know for sure. good luck and i hope you get it taken care of.

I see! Well thanks for letting me know about your setups.

Might anybody else have a stock FE fan diameter measurement? Larry's 18" figure is excellent, yet naturally, I always like to hear the same number from multiple folks before breaking out the credit card.

Larry and Fordman, thank you both for your quality replies.
Robroy

[fordman]

well ignore what i said about my dakota fan. the transmission went out tonight. and that may have been the motor reving to make the trans go. this truck isnt finished yet. and has several problems. so just ignore my earlier post. i am unsure why the engine was reving by itself. i still have eletrical issues. and now i have to swap out the trans. good thing i have another one.

[fomocoguy]

Good morning Robroy! I removed my stock fan last night in favor of an electric unit and just ran down and measured it for you. It looks to be about 18.25". I have a standard radiator, not super cool. Hope that helps!

[70_F100]

Overall, the clutch fan should provide quieter operation.

They are generally engaged when the engine is first started, but disengage rather quickly, once they reach a proper operating RPM.

Once the engine heats to a pre-defined temperature, they will engage long enough to bring it below that point, then disengage again.

[robroy]

Good morning Fordman, Joe, and 70_F100, thanks for replying!!!

well ignore what i said about my dakota fan. the transmission went out tonight. and that may have been the motor reving to make the trans go. this truck isnt finished yet. and has several problems. so just ignore my earlier post. i am unsure why the engine was reving by itself. i still have eletrical issues. and now i have to swap out the trans. good thing i have another one.

OK Fordman, thanks for letting me know! And sorry to hear about the transmission trouble.

Good morning Robroy! I removed my stock fan last night in favor of an electric unit and just ran down and measured it for you. It looks to be about 18.25". I have a standard radiator, not super cool. Hope that helps!

That is superb--thanks so much for measuring it for me Joe!!!

So it seems that an 18" or 18 and 1/4" fan is what Ford intended to fit in our standard cooling FE radiator shrouds. That's great to know since there seem to be a lot more 18" fans on the market than 19". And it explains the clearance issues I was having!

Overall, the clutch fan should provide quieter operation.

Excellent! Thanks 70_F100!!!

They are generally engaged when the engine is first started, but disengage rather quickly, once they reach a proper operating RPM.

Once the engine heats to a pre-defined temperature, they will engage long enough to bring it below that point, then disengage again.

That's just what I'm looking for, thanks! I've read on the Hayden thermal fan clutch page that depending on the air temperature at the front of the clutch, the clutch will cause the fan to turn at anywhere between 20% and 70% of its direct-drive speed.

So when combined with an 18" fan (instead of my current 19" fan), I'm hoping that this will provide a significant noise reduction. It's pretty funny as-is, because with the new exhaust, the fan's probably the loudest thing of the truck!

I might even choose a 5-blade 18" fan instead of a 6-blade, since it seems like it may be quieter.

Does anybody happen to know: when Ford equipped pickups of this era (or Dentsides) with clutch-fans, did they mate the clutch to the same five-blade fan they used for direct-drive setups? Or did they go with a more aggressive fan?

Fordman, Joe and 70_F100, thanks for much for your generous replies!
Robroy

[70_F100]

Robroy, IIRC, most of the clutch fans I've seen are of the 7-blade variety.

But, since I've got a bad case of CRS , I could easily be wrong...

[fireguywtc]

Robroy, something to keep in mind because of my past experience. Several years ago I decided to put an clutch fan on my 67. IIRC I still needed a small extension to make sure the fan was close enough to the radiator to work correctly. My 67 never had a shroud while it was running. Anyways, I was plauged with throwing my fan belts which I later figured out was because I was bending the water pump shaft. Luckily, I had just bought them and the parts store exchanged them for me.

I know that the increased weight leverage was causing the shafts to bend while it was running and then causing the pulleys to wabble, which is why I was throwing belts. Obviously the stock water pumps for our FE's are not built for a large amount of weight increase, but should be able to tolerate some. Hopefully someone can chime in and let you know whats acceptable. If you can eliminate the need for extension you may be fine, but I don't know. I just wanted to share to help you prevent a possible headache in the future. Good luck with your conversion!

[Hemmi06]

I went and measured the orginal fan shroud and clutch fan that worked with my setup before I went electric. The fan was from a dent and the same diameter as my original fixed fan at 18 1/2 inches. The shroud opening is 20 7/8 inches. One thing to double check is the overall length from the water pump to the blades. Mine went into the shroud too far and would hit the shoud till i fixed it. I agree that a fixed fan is loud that is why I went to a clutch fan (used from a yard) it gave away real quick.

[robroy]

Good morning 70_F100, Bill, and Hemmi06, thanks for your super helpful replies!

Robroy, IIRC, most of the clutch fans I've seen are of the 7-blade variety.

But, since I've got a bad case of CRS , I could easily be wrong...

OK, thanks! I think you're right about OEM fans. Based on the photos I've seen, they seem to have been mostly seven blade configurations, yet for whatever reason, it seemed like six-blade configurations were more common in after-market fans. Hopefully it will work out OK this way!

Robroy, something to keep in mind because of my past experience. Several years ago I decided to put an clutch fan on my 67. IIRC I still needed a small extension to make sure the fan was close enough to the radiator to work correctly. My 67 never had a shroud while it was running. Anyways, I was plauged with throwing my fan belts which I later figured out was because I was bending the water pump shaft. Luckily, I had just bought them and the parts store exchanged them for me.

I know that the increased weight leverage was causing the shafts to bend while it was running and then causing the pulleys to wabble, which is why I was throwing belts. Obviously the stock water pumps for our FE's are not built for a large amount of weight increase, but should be able to tolerate some. Hopefully someone can chime in and let you know whats acceptable. If you can eliminate the need for extension you may be fine, but I don't know. I just wanted to share to help you prevent a possible headache in the future. Good luck with your conversion!

Bill, thanks for letting me know about this! The weight of the new fan and clutch does seem to be a lot more than the factory extension and fan.

In my instance I'm not planning to use an extension, which might decrease the leverage on the pump shaft. I'm also using an Edelbrock Victor-series 8805 aluminum water pump, and I can imagine that its properties might be different from the OEM pump. I think I'll just have to put it all together, drive it, and wait and see what happens! Thanks for letting me know about your experience though.

I went and measured the orginal fan shroud and clutch fan that worked with my setup before I went electric. The fan was from a dent and the same diameter as my original fixed fan at 18 1/2 inches.

Superb--thanks so much!!!

The shroud opening is 20 7/8 inches. One thing to double check is the overall length from the water pump to the blades. Mine went into the shroud too far and would hit the shoud till i fixed it.

I'll be sure to measure that distance--thanks! I haven't installed my setup completely yet, but based on holding the parts up next to the water pump, it looks like I might need to space the fan closer to the radiator an inch or less, to get ideal, 50% fan blade engagement in the shroud.

I agree that a fixed fan is loud that is why I went to a clutch fan (used from a yard) it gave away real quick.

Indeed! That one I had installed previously sure was loud!!! Sorry to hear about your clutch giving out!

Today's Updates:

Based on advice from Dustin (AverageF250) in another thread, I ordered a Hayden 2710 fan clutch. It was only $32 from Summit and is USA made. I also ordered a Derale 17118 18" fan to get with it ($41 and also USA made). Thanks so much to everybody who spoke up here with their stock fan diameter!

It's also finally Spring time around here, which sure makes it more fun to work on #50. As you guys know, all of these photos can be clicked on to see much larger editions.



Here's the Hayden 2710 clutch. I was impressed to see that it was USA made after paying only $32 for it. Thanks very much to Dustin (AverageF250) for posting about this clutch.





The seal on the back appeared to be ever so slightly oily, but it didn't seem like it was leaking. Hopefully it will be OK!



It came with this water pump pilot size adapter, which turned out to be required for the Edelbrock 8805 pump (which must have the same pilot size as the OEM pump). It also came with some lockwashers, but I wound up using medium-strength threadlock instead (more on that in another post later on).



And here's the fan! It looks like a quality unit.





I'll post another update soon as I get these parts installed.

70_F100, Bill, and Hemmi06, thank you again for your generous help!!!
Robroy

[390Nut]

You wont be needing the fan spacer on the water pump anymore, in case it wasn't mentioned above (sort of skimmed through the thread). My clutch fan came off a dent that had a/c, is a 6-blade fan, and fits inside my original shroud with good clearance (can't measure it because the truck is parked at a friends place). My truck had the original 2-row radiator core in it until I replaced it about 10 years ago with a H/D 3-row, and the clutch fan didn't pose any problems for that upgrade.

[robroy]

'Afternoon Paul, thanks for replying!

You wont be needing the fan spacer on the water pump anymore, in case it wasn't mentioned above (sort of skimmed through the thread).

Indeed, it seems that way, although the fan looks like it could stand to be 1/4" or 1/2" closer to the radiator (more on that below).

My clutch fan came off a dent that had a/c, is a 6-blade fan, and fits inside my original shroud with good clearance (can't measure it because the truck is parked at a friends place).

OK, thanks! No problem about the measurement, since I've got that part tackled now (thanks to the help I've received in this thread).

My truck had the original 2-row radiator core in it until I replaced it about 10 years ago with a H/D 3-row, and the clutch fan didn't pose any problems for that upgrade.

Excellent!!!

This Afternoon's Updates:

Here I'm fastening the fan to the clutch using 5/16-18x1/2, grade eight bolts. The instructions that came with the clutch called for 5/8" long bolts, but I didn't have those, so I used these 1/2" long bolts instead. To make up for that, I skipped the lockwashers and used medium-strength thread-lock. Since the lockwashers were about 1/16" thick, I think it will be OK. I torqued the bolts to around 18 ft/lbs.



The fan+clutch flipped over:



Here's another look at the adapter that slid over the water pump shaft. This adapter interfered with the front face of the March water pump pulley, so it wasn't able to slide on all the way. It got far enough on there that I think it'll be OK though.



After another trip to the hardware store, I had these 5/16-24, 1" long grade eight bolts. I measured the depths of all the parts they'd need to pass through and came up with about 7/8", and the Nord-Locks are about 1/8" high, so these seemed like they'd be a good fit.



Here's the fan+clutch attached to the water pump, with the shroud ajar.



With the shroud installed, you can see the placement of the fan relative to the shroud opening. If the fan's ideally 50% inside, and 50% outside of the shroud opening, then this setup might benefit from being extended 1/4" or 1/2". I'll drive it as-is though for a while since it will probably be just fine, and finding such a short extension might be an adventure of its own.



I fired it up, and noticed immediately how quiet it was! This is an enormous improvement over the giant 19" fan I'd previously installed. I drove the truck a few miles and couldn't hear the fan at all! I suppose I'll only know how well this solution will work out by driving the truck under a bunch of different conditions, but I'm pleased so far!!!

Paul, thank you again for replying!
Robroy

[390Nut]

One very good option for extending the fan towards the radiator, is to take a stock fan spacer and cross cut it as thick as you need it. It is solid with the holes already where you need them. A little deburr here and there, maybe polish it up to match those pulleys, and you're in business.