Radiator fan drive.

[TomC]

The only place I've seen electric radiator fans (like 8 of them) used is in transits-since they are doing stop and go (translated heat up and cool down).  Try pulling a long hill in hot weather, and you might not like the out come.  Good Luck, TomC

[robertglines1]

Eric Jim tried elect if I'm not mistaken and finally went with a hydraulic might ck out his blog. I'm at that point also on fan selection as I don't have the original miterbox.   Bob

[dickegler]

Eric, here's what I did with a 6V92 transplant into an 05 Eagle.  I used a right angle gear box, and drove the original fan bub by belt.  Takes a little engineering to get the fan speed right, but all in all pretty simple.  Belt from the engine uses a spring loaded idler pulley.  Pay attention to make sure the fan runs the correct rotation.

Dick Egler

[Ericbsc]

I think thats what I am leaning toward. Jeff Jefferson has all the parts either way. I can sell the trans. pto if I go right angle box.

[luvrbus]

Eric, like you I love Jerry but you will find Prevost is going to be a lot cheaper on that setup than Jefferson,plus it doesn't take up as much room as the Eagle angle fwiw


good luck

[JohnEd]

Speaking of fans....

I once read a comparison between shrouding the fan and not doing so.  It was a large difference and demonstrated that shrouding should be a big part of your design. All shrouds aren't equally efficient.

Fan speed is critical.  Using a clutch adds a lot of efficiency.  I have heard others say that they deleted the fan clutch to gain reliability.  I think that is poor logic given that reducing the cooling load returns real dividends.  I am certain that they are not all created equal and some must be better.  Cost???  Are hydraulic  drive fans more easily speed controlled?

Over sizing the rad will also pay you back as you don't need to run the fan as hard or as long.  That is built in efficiency that, I think, goes pretty much unnoticed.  If you are going from a 8V92 to a series 60, or even from a 6V92 you probably have more rad than you need.  That was Brians finding and he also loaded the cooling sys with two inter coolers in front of the rads in his MCI.

The fan blades in modern engines are molded plastic.  They move much more air than the metal ones of yesteryear.  They are "efficient" and well worth the investment.

One of the Knuts here went all the way with his cooling sys design....new hi efficiency fan, shrouds, bigger rad and fan speed control tied to cooling load.  He said he cut his power consumption attributed to cooling in half.  HP is HP and he claimed to get a additional MPG for his efforts.....if memory serves.

Boy?  Isn't anything any more ever a "no brainer".

If anything in this post isn't correct or can be amplified I am happy to learn it.

Good luck with the adventure. 

[rv_safetyman]

John is correct about the impact of the shroud.  However, the Eagle shroud is fine and all you need to do is to make sure the fan blade is the same size and located at the same depth as the stock fan.  You can get a higher flow fan that can move a lot of air. However, the trade off is that moving more air means more HP.

On my conversion, I used a fan hub off off a truck with an air clutch and mounted it where the Eagle bearing hub is.  The original thought was that I would use the Series 60 clutch control circuit, but that did not see to work.  However, I can control the the clutch from the driver area.  I find that even in reasonably cool conditions I have to run the fan full time.  Our side radiators don't have any forced air and trying to used some sort of ambient flow just does not work.

For my gear box, I used an industrial box.  On page 4 of my project pages (see signature) I have quite a few details and photos about the fan drive modifications.

Jim

[JohnEd]

Jim,

Thanks.  I didn't hear any contradictions.  I do see something that indicates a inefficiency, however.  If your fan is fully engaged while you cruise down the road....and all is well......then you climb a hill....and all is well.... you must be wasting energy while going down the road and probably while climbing.  It should take less air to cruise than to climb and all climbs are not the same difficulty.  This relates to the fan clutch being variable in coupling.  I thought( yeah, I know) that the hydraulic drive "could" lend itself to being more controlable.  What is a HP per mile saved worth?  30 per? Sean?  Clifford?  There is a cost to benefit trade off here but I can't figure it out accurately.  I do know that a 1 MPG increase is a 20% reduction in fuel cost and that would add up to $134 reduction in 1000 miles if you started out getting 5 MPG and fuel cost $4 per.   So if you can save $1000 in 7.5K miles with that improvement.  There must be a saving in wear and tear having the engine do less work per mile.

This is the same argument for getting synthetic lubes in the diffs and drop boxes and bearings and transmissions.  And the engine if your 2 stroke isn't drinking/leaking the $4 per quart crankcase oil.  All my rolling stock is changed over for that reason alone and the added wear protection is a bonus.

John

[rv_safetyman]

John, you make a good point.  The question is how far do you go?  A couple of folks have tried two speed gear boxes.  There is supposedly a two speed fan hub with some sort of lockup clutch.

I don't watch my % load gauge on my SilverLeaf all that much, but when I do look, it is usually over 30%.  On my engine that is 30% of 500 HP.  The savings in fan HP would be a pretty small percent.

Also consider that the fan speed/load at cruise speed (~~1500 RPM) is much lower than climbing a big hill where I drop a gear or two and run at 1900 or more RPM. 

I designed my belt drive system to be able to change the speed ratio by perhaps 20%.  Never played with it.  I think I have it at the slowest speed right now, but would not swear to that.  When I designed the two belt drives, I selected inside idler pulleys that could be interchanged with the driver pulley.  On paper that gives me something to play with, but never did.

Jim

[JohnEd]

Jim,

Thanks.  My point may also be academic and not get any traction in application.  But, at this point, if I were designing my system, I would be getting info on that two speed fan with the lock-up.  All the while nagging Clifford about any down side to that item and where I could score one for the least....

John

[Ericbsc]

The engine I have is out of a volvo truck. It has the fan hub assenbly still on it. The hub has an air clutch on it. I thought about using that but I don't know if there would be an advantage to it?

[luvrbus]

Use the clutch Eric you will like it so nice to cut the fan off when pulling off to a dusty place or running in very cold weather fwiw I like the 2 or 3 speed clutches I believe Wayne is going to use the 3 speed on his new bus

good luck

[Boomer]

I'm with Clifford.  Don't forget your intake air temp also.  Besides coolant temp, the intake air temp will also trigger the fan on. This is done through the ECM.  There should be a fan wire pin on it. I would rig the fan clutch through relays and install a switch (or switches) in the cab so that you can manually activate the fan.  I have two switches on the dash to manually control my fans.  The intake air temp set on the ISM is around 165 deg.  Should be aprox. the same on your S60.  When the engine is hot and sits a while the intake air temp will naturally gravitate up a little, so don't be surprised on a restart when the fan comes on for a few seconds.

[Hal]

I use what Horton calls a three speed  clutch although I only use two speeds.(they call stopped a speed) The clutch uses magnets that pull the fan along at about 30% engine speed until the engine calls for more cooling and the clutch locks up to provide full (108% of engine speed) cooling.I drive the clutch from the crankshaft pulley by belts with a drive shaft going forward to a right angle box with the 34" fan attached.The fan will consume 52 hp at full pull (rpm) but seldom runs-less than 5% of the time I'd guess. My radiator and CAC are side by side with a common shroud. This is the same type system MCI used in their E series coaches but with a much larger CAC (a 14litre s60, 600+ hp needs LOTS of cool air when at 34lbs boost) I mounted an air to oil cooler behind the fan to cool the world trans-keeps the heat load out of the engine's water and keeps trans temps between 150-170 summer or winter. This system has worked great in my 43,000+ lb Eagle with zero heating issues from my part of the country (Las Vegas, NV)

[Ericbsc]

Hal, Do you have a part number for the three speed fan. I looked on the Horton site but do not know witch one you are talking about. Thanks!!