Community Forums

Rocky68D · 05-31-2015, 03:04 PM

I've noticed that different manufacturers seem to have different philosohies as to what kind of cowl they put on the back of their DP coaches. Looking at just the models with side radiators, Monaco/HR have what appear to be nearly solid access panels/doors to get to the engine. Newmar has large louvers in their panels which, it seems to me, would allow the heat to escape more easily. All of these models I'm considering use the ISL 400.

Can those who have experience with these designs explain the pros and cons?

As always, your input is appreciated.

DGBPokes · 05-31-2015, 03:36 PM

Another observation about Newmar. High, high on the left corner is the air intake......high to means less likely to suck in dirt and dust from the rear wheels on bad roads. Longer filter life, enter engine performance.
Have no idea what the other manufacturers do

SpaceNorman · 05-31-2015, 03:44 PM

Our 2012 HR Endeavor has a couple of different "radiators". The engine radiator is in the rear - behind what strikes me as a very large and very well vented panel. The transmission radiator is behind a louvered door near the rear of the coach on the driver's side of the vehicle. Both can be seen in the picture below.

Note that that 4 large openings in the rear are screened vents for the engine radiator. Although it's hard to tell in the picture - the four smaller openings to either side of those are in fact the rear lights.

The small opening up high on the left corner is the air intake.

PushedAround · 05-31-2015, 03:55 PM

Personally, I think that the side radiator (as compared to a rear one) is really a convenience thing, enabling you to more easily get to the "front end" of the motor to service the drive belts, alternator etc. Yes, maybe the air off of the side of the coach is a little cooler, and maybe a little cleaner, but the cost is 2 whole compartments of storage on that side, and a whole lot more complexity to drive the fan. And proper sizing of a rear radiator will make up for the slight amount of added heat coming off of the motor & exhaust.

A rear radiator can save your bacon though. My Horton fan clutch stopped working on the way to Key West, and because of the air flow under the coach and through the radiator, I was able to very gently drive my coach for over 200 miles until the darn thing just started working again. I did get it repaired after the trip.

ShapeShifter · 06-01-2015, 11:37 AM

Quote:

Originally Posted by SpaceNorman

Our 2012 HR Endeavor has a couple of different "radiators". The engine radiator is in the rear

He's talking about coaches with the engine radiator on the side. By definition, all rear radiator coaches are going to have large ventilation grilles behind the radiator.

What you're calling the transmission radiator on the side is actually the condenser for the dash air conditioning.

96 Wideglide · 06-01-2015, 12:01 PM

Quote:

Originally Posted by Rocky68D

Looking at just the models with side radiators, Monaco/HR have what appear to be nearly solid access panels/doors to get to the engine. Newmar has large louvers in their panels which, it seems to me, would allow the heat to escape more easily.

Holiday Rambler, (and I assume Monaco's) changed the engine hatch design during the 08 model year, to allow more engine compartment heat to escape.
You can see the opening, just below the third brake light on mine. That opening is about 7" deep.

Rocky68D · 06-01-2015, 01:28 PM

I saw an '06 HR Scepter on a lot and the engine access was 2 doors that swing out with only about an inch gap at the top. Lots of crud on the inside of the doors that I suppose would be on your toad if it had lots of louvers.

Mr_D · 06-01-2015, 01:36 PM

Back of our rig, seems to be enough for our side radiator and ISX. Overheating has never been a problem even when the engine dropped a valve it still didn't get hot.

96 Wideglide · 06-01-2015, 01:42 PM

Sounds like it had some sort of engine oil leak, or, the previous owner was simply overfilling the oil.

Route 66 · 06-01-2015, 01:43 PM

Side radiators draw air in from the outside.

Rear radiators push air out from the inside and some folks state they have more problems with dirt/oil/etc. on the cooling fins.

Sheriffbubba · 06-02-2015, 11:06 AM

You guys sure have some very nice looking coaches.... Just beautiful.
Mr. D, I have read about your Cummins ISX engine woes. I hope those are all solved now. The model that you have is the one that I would love to own some day.

Sent from my iPad using iRV2 - RV Forum

Crasher · 06-02-2015, 02:09 PM

Generally, but not always, when the hp gets to 450 or above, it will have a side radiator. This allows for cooler air flow, but also a larger radiator needed to cool the added heat from more hp. Some use a hydraulic fan, however, ours is belt driven through a gear box. Some 400 hp coaches use a side radiator and a few 450 hp ones use a rear one. I have never seen a 500 hp or higher with a rear radiator. They just can't keep all of those pony's cool.

SteveLevin · 06-02-2015, 02:54 PM

Mine has some fairly open grating, which seems to let the air escape. With everything working, my coach (admittedly with just an ISC) will climb the Grapevine (a 6 mile, unbroken 6% grade) when it's 100 degrees out and only rise 15 degrees on the coolant.

Steve

Koop · 06-02-2015, 05:16 PM

On our Alpine Coach, we have a side radiator and no louvers or grill in the back. One thing to consider is the flow of air exiting the engine compartment. If you have a mudflap that completely covers the space from the rear cap to the ground, air flow is limited. Our mudflap is a few inches off the ground and also has a couple of inches between it and the bottom of it and the rear cap. We run cool temperatures with no problems.

It's happy hour so I hope this makes sense to anyone reading.