Horton Fan Clutch

[Jestme13]

I have located a Viscous Fan Clutch, Horton PN 9905000 that is supposedly for all 2004 - 2007 Cat C7 engines. However when inquiring about an install of said kit at Freightliner the problems start. FLCC says the kit works with a radiator called a world something and it has a measurement of 1050 sq inchs. My coach serial #s reflect my coach having a different radiator that measures only 1000 sq inchs and that the clutch kit does not work on my application. ???????.
I cannot find anyone who can explain to me why not, including Gaffney. Does anyone out there have a clue, or is this info regarding the kit fit BOGUS.

[Jestme13]

I have located a Viscous Fan Clutch, Horton PN 9905000 that is supposedly for all 2004 - 2007 Cat C7 engines. However when inquiring about an install of said kit at Freightliner the problems start. FLCC says the kit works with a radiator called a world something and it has a measurement of 1050 sq inchs. My coach serial #s reflect my coach having a different radiator that measures only 1000 sq inchs and that the clutch kit does not work on my application. ???????.
I cannot find anyone who can explain to me why not, including Gaffney. Does anyone out there have a clue, or is this info regarding the kit fit BOGUS.

[Gary RVRoamer]

Why don't you contact Horton and ask them if it works? Or at least if there is some minimum radiator size that it can used with.
Horton Worldwide

Obviously any variable speed clutch has to be designed to provide sufficient air flow over the radiator to keep the engine cool. A viscous clutch controls itself via its own internal mechanism and not the measured engine temperature, so it has to be mated to a suitable size of radiator and fan blades. Smaller radiators need more air flow than larger ones to provide the same level of cooling, so radiator size vs airflow is an important consideration. Whether the radiator you have is too small for the Horton Viscous clutch is hard to say and I suspect that FL simply does not want to go out on a limb and tell you that some non-standard fan drive that they have not tested is OK. You would be mad if they were wrong and might sue them if the engine overheated as a result, so they are not likely to OK it.

[Jestme13]

Thanks for the reply Gary. I did speak with Horton techs. they informed me that their kit would work, when I contacted gaffney for an install they knew nothing about this kit. Further research by FLCC revieled they never tested this kit on the 1000 sq in radiator, thus its not approved. I find it hard to believe that 50 sq in will make that much differance in a radiator of that capacity. Also this clutch is tied into the ECM control to regulate tempature on/off. FLCC mostly uses a radiator called a world class 1050 sq in. Very few chassis are fitted with a 1000sq in. Lucky me.

[Gary RVRoamer]

It is my understanding that the ECM connection for the fan is strictly an On/Off. The viscous clutch controls the SPEED that the fan runs at when it is on, with the viscosity of the drive hub increasing as the temperature increases. The potential problem is that the ECM says to turn the fan on and it does go on, but the thermal control in the clutch has it running too slowly to adequately cool the radiator. That's where the tie-in with the radiator size comes in.

Like you, I doubt if the 50 sq in difference is significant - we are talking 5% difference. But diesels shed a lot of heat and radiator size IS a known, critical factor in proper cooling, so FL is not going to risk approving something they have not tested.

You are going to have to risk it and watch the temperature gauge closely.

I have heard there is a FL approved variable speed fan but don't know the make or whether it is approved for your size of radiator.

[hondo122]

Steve, did Horton give you any info on the power (eg mph) savings with this setup. Which system is it exactly, I went to Hortons site and couldn't find a search engine for the part#.

[historyljc]

If I recall correctly, when I was attending Camp Freightliner in March it was mentioned that my always on single speed radiator fan could be upgraded - for around $2,000.00. Since my rig runs good and runs cool, I quit listening about that point to the fan replacement conversation.

[Jestme13]

$2000. Holy Moly Batman, not hardley worth the expense. Hondo it is there, put the part # in Hortons parts # search box.

All I can say right now gang is, STAY TUNED

[Gary RVRoamer]

As I recall the parts for the Freightliner approved fan upgrade were something like $500, so the rest of the $2000 would have to be labor. If you pay somebody else $100/hour to remove and install a fan clutch and wire in the variable speed control stuff, it could run up a big labor bill. Don't think it would be 15 hours worth, though.

[historyljc]

It may depend on whether on not they want to do it. I had one dealer quote me over $600 to install 4 shocks. That's just the labor. They recommended that I go down the street to the big truck tire dealer. I did, and got it done for $150.

[Jestme13]

Gary, What dealer has the freightliner <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Approved </div></BLOCKQUOTE> Parts kit list. I understand there is no such animal from FLCC as of this date.

[vicsryd]

Several of us in FCOC have purused this option for a couple of years. You can download my copy of part list spreadsheet with instructions here. One tab on the spreadsheet is for Cummins and one is for CAT.

Be aware this parts list is specific to chassis built after a certain date by engine type. Date ranges are listed on the top of the parts list. You may be able to still do the retrofit with earlier chassis (i.e. mine was built 4 months too early for this list) but word is that can be fixed by using a different fan. In some cases though I've heard you may need to upgrade the whole cooling package.

Also be aware FL has not produced a technical service bulletin for this upgrade and so the exact procedure and labor hours are not framed up for the dealers. Hence, any given dealer will estimate whatever they see fit for labor.

There are two folks I know who have done it themselves. One is a retrofit back to a CAT 3126E (CAT C7 predecessor circa 2003). I have not yet heard of the the upgrade being performed by Gaffney.

[Gary RVRoamer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">What dealer has the freightliner Approved Parts kit list. </div></BLOCKQUOTE>

I thought there was one, developed after the issue of horsepower loss due to the constant speed fan on rear radiator models was raised by several FCOC members and discussed at some length in the FCOC Yahoo group. Perhaps I overstated that there is an "approved" set of parts, since I don't personally have a copy nor have I seen one. I doubt if anything was ever formally issued to dealers, but a call to FL Custom Chassis Parts might get you a list that will work for your engine and radiator.

See Jon Pritchard's parts list spreadsheet in the post just preceding this.

[Jestme13]

All I can say myself right now is " stay tuned, news at 11"