ISL400 Fan Clutch

[hardy1000]

My friend just got back from the Monaco ralley in Tuson and was speaking with the guy camped next to him about different mods that he has done on his motorhome. One of the mods that he spoke about was a clutch fan that he had installed on his ISL400. He told my buddy that he now has more power and that he gets 1 MPG better than he did with the direct drive fan. He also stated that if you buy the fan Cummins would install it for free or next to nothing because they strongly believe in it.

Has anyone actually done this? Do you have the same results as described?

Any comments would be appriciated.

[walt2137]

Yes it was a guy on the MCOA board that stated about the same thing only with a ISC engine in a 02 Dip, he went from 8.1 to 9.3 and it a 2 speed fan

[Happycarz]

There are quite a few discussions on the advantages of the Horton fan clutch on this forum. Go to the "Search" at the top of this page and type in Horton

[Corkey]

Quote:

Originally Posted by hardy1000 My friend just got back from the Monaco ralley in Tuson and was speaking with the guy camped next to him about different mods that he has done on his motorhome. One of the mods that he spoke about was a clutch fan that he had installed on his ISL400. He told my buddy that he now has more power and that he gets 1 MPG better than he did with the direct drive fan. He also stated that if you buy the fan Cummins would install it for free or next to nothing because they strongly believe in it. Has anyone actually done this? Do you have the same results as described? Any comments would be appreciated.

I had mine done by Cummins Coach Care in Coburg, OR last year. It's actually called a two speed fan. Yes it has a clutch, but is also viscus and slips untill the clutch is needed. As delivered the fan is hard-coupled and the newer (post 07) ISL400 has a larger, noisier fan.

The very first thing I noticed was the fan ROAR was totally gone when I left the Cummins shop. As I pulled out on the interstate the power was MUCH better, I mean very noticeable. Finally after a year of driving, my avg fuel improvement is 1.5 MPG higher than the previous average. Cummins claims the fan requires 40 HP. Letting the fan free wheel untill it's needed frees up a ton of HP.

The cost was around $1200, not cheap. But I'll never look back, I'm that happy I'll never miss that awful fan roar from the hard-coupled fan.

Oh, did I mention it was QUIET?

[Bill2]

Yes, I had it installed at the Elkhart Service Center before they closed down. It was installed by the Cummins guy named Jack. It cost me $750.00 but that was two years ago. I gained the lost 26-30 hp back and gained at least 1 mpg at the time. I haven't checked it lately and maybe it is a little better now. I watch the temp gage on the Aladen Jr. and when the temp gets to about 209-210 degrees the fan kicks on. It only stays on for long enough to cool the engine down to the 180's and then it cuts off. That takes just a little while. Actually it hardly ever comes on, especially in the cooler areas. I love it.
Bill O.

[hardy1000]

Quote:

Originally Posted by Bill2 Yes, I had it installed at the Elkhart Service Center before they closed down. It was installed by the Cummins guy named Jack. It cost me $750.00 but that was two years ago. I gained the lost 26-30 hp back and gained at least 1 mpg at the time. I haven't checked it lately and maybe it is a little better now. I watch the temp gage on the Aladen Jr. and when the temp gets to about 209-210 degrees the fan kicks on. It only stays on for long enough to cool the engine down to the 180's and then it cuts off. That takes just a little while. Actually it hardly ever comes on, especially in the cooler areas. I love it. Bill O.

Bill, was the $750 for the fan and labor? Did you get the fan from Cummins?

Thanks for your input, I appriciate it

[Our Time]

We also had the Horton fan installed 2 years ago. It improved the power and after 14000 miles a increase of 1.1 MPG to a average of 9.1 towing a 3400# Toad. Our fan was installed by Jack Markin of Cummins Crosspoint, Ft Wayne IN 800-777-3691 cell 574-535-8448 email jack.l.markin@cummins.com He furnished the fan and installed it for $800.00.

[hardy1000]

Thanks everyone, looks like it is worth it.

[Joe-K]

I'm curious for those that are installing the Horton fan.....are you installing those on rear radiator ISL engines or do you have a side radiator direct drive fan?

Our rig with the side radiator has the fan driven by a thermostatically controlled hydraulic motor so it already is driven according to the cooling needs.

[Corkey]

Quote:

Originally Posted by Joe-K I'm curious for those that are installing the Horton fan.....are you installing those on rear radiator ISL engines or do you have a side radiator direct drive fan? Our rig with the side radiator has the fan driven by a thermostatically controlled hydraulic motor so it already is driven according to the cooling needs.

Side radiators are not direct coupled to the engine. Only the rear radiators are direct coupled, similar configuration to your car.

Side radiators are either hydraulic or electric. Some are variable speed which is even better than a rear radiator two speed. But the cooling system is located at the side of the coach separate from the engine. For the rear radiator, the fan is connected directly to the engine.

[Batman_777]

From what I've heard: Pros and Cons

Rear radiators require less hp from the motor than side hydraulic radiators which can take 30-70 hp away from the motor; however, rear radiators are always on to some extent. Rear clutched radiators are like your clutched car radiators. Most coaches today use direct fan (non-clutched) fans.

Rear radiators have one advantage over side radiators, they draw from in motion forced air cooling, but also tend to draw dirt in as well.

Side radiators take up precious cargo space

Designs require larger engines to use side mounted radiators due to larger cooling demands.

Rear mounted are more efficient but limit the amount of cooling due to size retrictions and force manfactures to use larger side mounted radiators.

[Harry B]

I assume that this application is for coaches with rear mounted radiators?

I have a side mounted radiator on my ISL400, which has a hydraulicly driven fan. As I understand it, the drive to this fan is temperature regulated.

[Batman_777]

Whether rear or side, it's what the application required for cooling amount that fits. Yep, the hydraulic fan is temp regulated and other criteria.

[Bill2]

Hardy1000,Yes, that price was for everything, including the tax. They came to the
Elkhart monaco service center and done the work, he brought the fan with
him. It took about 45 min. to do it as I recall. The price may be somewhat
higher now.
Bill O.