Side or rear radiator diesel pusher

et2 wrote:
Are you saying the air to cool is coming off the outside of the coach into the bay? Is this true? Can someone confirm. If so I would think that is a big advantage - cooler air.

Yes, with a side radiator, air flows from the side of the coach through the CAC (Charge Air Cooler), then radiator. The fan(s) are inside that/in the engine room and SUCK air from the outside.

With a rear radiator, air is sucked from below, after passing over the (hot) rear axle, transmission and engine. The fan pushes it into the CAC and then the radiator (except on stacked systems where the CAC is above the radiator).

et2 wrote:
LOL - I want one just because it's different. Can I get a new MH?

Ray Chez post made a lot of sense. The one poster who said the side gets fresh air, not from the engine area. Are you saying the air to cool is coming off the outside of the coach into the bay? Is this true? Can someone confirm. If so I would think that is a big advantage - cooler air.

It is true that the side radiator sucks the air through the radiator from the side. While the rear radiator also sucks the air from outside also, but through the bottom into the box and out through the CAC and then out the radiator. So it is the same principal getting rid of heat from the engine. One sucks air and down the engine while the rear works just the opposite. Sucks the air from under the box and pushes it out the rear.

The only big advantage that I see with the side is changing the belts at probably eighty to a hundred thousand miles. They are all different and that is why you have to check them every so often. Other then that you can not do much more on the engine from the rear. Filters are easy to change on either one.

Ours is a rear radiator and I like it. While moving on the highway the big rear area of the coach is a low pressure area due to the large hole the coach makes in the air. This greatly aids the fan in moving heated air thru the CAC and the radiator which greatly increases the efficiency of the system.

I changed the fan belt last December and the hardest part was getting the cold belt past the damper and the motor mount done from underneath. I was able to move the tensioner from inside the coach. It was not hard at all.

DSDP Don wrote:

Monaco's Roadmaster Chassis stacked the Charge Air Cooler (CAC) above the rear radiator, where everyone else was/is stacking them one in front of the other. The Monaco design was the best, since you could get to the front and back of the CAC and radiator without a lot of effort. The other brands made/make it a nightmare to clean between the sandwiched units. No matter if they have a slobber tube or not, you'll have to get in there and clean between the two at some point.

Ours has the CAC above the radiator, in the back. I clean it every couple years, and appreciate that easy to access design.

As for engine maintenance, I've never missed it. Someday I'm going to have to change the belt, and I'll wish I could get in there. Side rad, you can practically change it from across the street.

Unlike the older, sandwich systems with slobber tube and dirt, our unit cools very well, never ever above 180, on any weather on any climb

LOL - I want one just because it's different. Can I get a new MH?

Ray Chez post made a lot of sense. The one poster who said the side gets fresh air, not from the engine area. Are you saying the air to cool is coming off the outside of the coach into the bay? Is this true? Can someone confirm. If so I would think that is a big advantage - cooler air.

I have a rear radiator and can have the radiator out in 45mins by myself and it has a computer controlled fan drive.
But if I ever buy another it will be a side radiator.

Labor cost! Techs have to work around, over, through or under a rear rad! Takes longer costs more.

moisheh wrote:
Ray Chez: You make some interesting comparisons but missed on the HP used. A rear rad usually runs constantly. No variable speed. Thus it is using HP all he time. A side rad only draws HP when the fan is running. And the fan speed is variable.

That is very true moisheh, but as you know the fan will be idle only while standing still when you first start the engine. Once the coach starts rolling and the temperature rises to around 200 degrees the hydraulic fan will cut in at low speed. So then when you start climbing a long grade the temperature will rise to about 210 on most ISX Cummins engines and the fan goes into high spin, your fuel mpg will drop from 7mpg to 4.5mpg. The hydraulic fan in the mean time will take considerable hp away from the engine causing the engine temperature to rise on those long grades. A lot more then a belt driven fan.

Another thing that I used to hate about side radiator fans is that every time one would come into the Morgan Hill Thousand trail Resort they would stir up a dust storm with the fan blowing the air onto the engine and then down into the ground. Most RVers hated to see one come in especially after they had just washed their coaches. LOL

Go with the side morel...

Ray Chez: You make some interesting comparisons but missed on the HP used. A rear rad usually runs constantly. No variable speed. Thus it is using HP all he time. A side rad only draws HP when the fan is running. And the fan speed is variable.