Overheating Problem

[Don Hircock]

When driving from Denver to Grand Junction last Oct and now in June driving the opposite direction I have encountered no power and over heating problem.  Driving on basically flat and level with some rolling hills it is running 200 degrees.  Used to always be 185 degrees.  Yes, much hotter going over the hills in 2nd gear.  Beaver has been in to Wagner Cat here in Denver for about two weeks.  It has been run on the dyno and was determined that new radiator was needed.  New side radiator installed and they took for test drive.  Went west on I-70 up to the Morrison turn off, if you are familiar with that.  The start of going on up into the hills.  Engine overheated again.  Pump, hoses and things I didn't even know existed have been checked.  They are doing some more tests today but if nothing is found I guess I get it back after several thousand dollars spent with no solution. They have talked with Monaco and I gave them Beaver Coach Sales number which they are going to call today.  Any ideas out there.  Thanks for any input.

Don
2005 Monterey
Cat C-9

[Gerald Farris]

Don,
The only thing that I can think of is the control valve for the cooling fan motor or the fan motor itself, assuming that they have properly cleaned the charge air and hydraulic coolers and all shrouds are in place.

Gerald

[Don Hircock]

Gerald,

Thanks for reply.  Fan has been totally checked out.  Only thing they thought was that it could have more pitch.  As far as operating properly it is.  Shrouds are in place, don't know about the cleaning of two items you list but will suggest that to them.  Thanks for the help.  They are frustrated and so am I.  Now I just find out that hotel is booked tonight and we will have to move.  What next?

Don

[Larry Fisk]

I assume the thermostat is working properly. I know, that's an obvious thing to check but just a thought

[John Hennessey]

Temp sending sensor?  

[Bill Schneider]

I am having a similar problem. The only difference is I have a rear radiator.  My coach still does run around 180 to 185 on level roads depending on outside temp, but climbs quickly to 200 plus on any grade. I have had the radiator cleaned, flushed and use ELC. They did not change the thermostat during this service and I regret not thinking about it at the time. I am thinking this may be my problem. Any help is appreciated.
Thanks,
Bill

[Don Hircock]

My thermostats were changed when I had the 5 year old ELC changed in Grand Junction.  Temp gauge not being relied on as it is a joke. Cats instruments and the Aladdin agree on temp.

Don

[Peter and Connie Bradish]

Have similar problem.
We have had temperature sensors changed twice, water pump replaced, expensive solenoid replaced, all to no avail. Presently at Bend RV Repair. They have checked fan speed and hydraulic pump. They seem OK. We are in process of replacing radiator (21 years old).
Really hope this will solve the heating problem. Like you engine used to run 180 to 185 all the time. Now on flat runs same but climb any hill and temp starts going up. Temps have reached 200-210. Also transmission temps used to run cooler.
Will keep you posted as to results.
Never a dull moment in the RV world.

[Orman Claxton]

I have had that problem since day one on my 2005 Beaver Monterey 400 HP.
I talked to Cat in Ore. I was told keep the RPMS up, manual shift transmission if necessary.
I then talked to Tom @ Massey Diesel,he says the same thing, keep rpms up around 2000 or higher especially climbing hills
Makes sense, listen to the long haul trucks, they keep the eng RPM high, you can hear it.
I tried it, it works!
I am adding an Electric fan, this would only work when the Dash AC is running, Just get more air across the Radiator.

[LarryNCarolynShirk]

On the side radiators, dirt builds up between the charge air cooler and the radiator.  When they are separated, you may find partially clogged space.  Removing that dirt (straw, twigs, leaves etc.) will improve air flow.

On our rear radiator '98 Patriot, changing from Dextron to TranSynd transmission fluid, reduced the temperature about 20 degrees in both the engine and transmission.

Larry

[Dennis Crawford]

There could also be an issue with the PTO at the Alison transmission. I don't know all the detaills, but there is a component that does not get proper lubrication and impacts the hydraulic fan.

Dennis

[Steve Huber Co-Admin]

Some suggestions similar to Ormon's; Be sure that you are not lugging your engine. If you have a GPS that can display elevation, it will help you determine when you are on long slight degree climbs. These will also cause temps to rise, even though the tranny stays in 5th or 6th. Also, don't use economy mode when driving areas with hills. The delayed shift points will cause the engine to lug and temps to rise. When climbing, downshift before the cruise control does and keep it in the lower gear as long as the climb continues. Watch your temp on the Silverleaf and you can see if it is climbing or decreasing, based on grade and RPM. If temp continues to climb, downshift again. In AZ, I'm often climbing in 3rd as that gives me the best temp / power combination. This applied to my Contessa with a 3126 and is now true with the  Marquis /C12. Actually I need to watch the C12 closer as it has the power to climb at higher gears, but you pay the price in temperature. Bottom line, watch your engine temp and use RPM to manage it.
Steve