Overheating help

[Dahood]

Hello, new here, my hubby and I bought a 2008 fleetwood disc, 40x RV. We love it. Only problem is, we get an overheating guage pop up when going up a grade, and have to basically creep at 25 mph up a hill in order for it not to get hot. Its a diesel with 25k miles on it. everything on it is great for its age. But we have no idea wy it heats up even in cooler weather. Any help will be appreciated.

 

[Joe Hogan]

You might check the radiator for dirt. Run some water at low pressure over the radiator and see what comes out.

 

[Dahood]

You might check the radiator for dirt. Run some water at low pressure over the radiator and see what comes out.

oh my gosh, its funny you say that, my hubby mentioned something about the radiator. And how someone he spoke to just in conversation said the same thing. but we thought it too easy to try, but thats my go to NOW. Thank you so so much for responding so quickly, i already love this forum

 

[Dahood]

You might check the radiator for dirt. Run some water at low pressure over the radiator and see what comes out.

so I checked with the hub, and he already did that. I wasn't aware. He says its clean all the way around, no build up or anything. Sorry I wasted your time, , any other ideas out there are appreciated.
Ty

 

[Joe Hogan]

Next check belt tension and fan clutch, if any.

 

[AbdRahim]

2008. When was the last time the radiator was flushed. If you haven’t already, I would have a good mechanic check the entire engine and chassis, to avoid surprises.

 

[Kevin D Pem]

2008, 16 or 17 years old! Most of the users here are meticulous about maintenance. I would say to a fault! But that's subjective. Most rubber is replaced by now if maintenance schedules are kept. But what if they haven't been? So what can you look for?

Coolant has degraded and should have been replaced at least twice.


If Coolant has not been replaced corrosion may be an issue! Did they keep records?

With no records I would flush, or have flushed the Coolant system. This procedure includes replacement of the thermostat, and hoses.

You know that the oil is a big part of the cooling system, right?( oil levels, oil coolers all play a part)

Diesels don't like to be lugged down! Lower gears, and higher RPM will help keep her cool!

I was hesitant answering this! Let me tell you why!

Cooler temperatures toward the end of summer in Phoenix are still considered hot in many locations around the country! I'm still dealing with 111deg where I am located.

A climb from 1200 ft to 7000 in under 100 miles is normal when leaving the desert floor. Such conditions are very hard on a well oiled machine, and require a learned action. I have no idea where you hail, so it's hard to answer your question honestly!!!

To some here these conditions aren't even on the radar!

So let me ask! Where do you hail? What is Cooler? What grades are you pulling, and for how many miles? You may get told a really simple solution!!!

 

[B52Bombardier1]

Sticky, original thermostat? Rust and scale inside the motor water jacket due to poor coolant change service - the rust inhibitors and water pump lube degrade over time, not miles - also leading to premature water pump wear.

And as advised above, fan clutch viscosity changes over time, not miles. This results in the fan being unable to move air through the radiator fins.

Rick

 

[Just George]

Given the age of the MH and undefined maintenance history all of the above comments seem reasonable.

I'll just echo Kevins comment regarding diesels don't like to be lugged down. So when going up a grade you may need to manually down shift to keep the engine rpm up. I don't know your particular rig but my guess would be the engine peak output is somewhere around 1600 rpm. Keeping engine RPM up means the cooling fan (when working properly) is spinning faster, and the engine is producing peak power.

Regarding up hill speed. Again I don't know your rig but depending on the grade 25 mph may be all you should expect. Many Motorhomes struggle on steep grades.

 

[Joe Hogan]

thinking about this unit with unknown history, it could be anything from Coolant, Coolant system, to fluid level/quality, Trans fluid, rear diff fluid, dragging brake shoes/pucks, bad or dry wheel bearings or simply being overweight. You get the picture.

After thinking about how I would treat this, two or more pages of notes, it came to the most reliable way to get a good baseline for the Coach is to get the chassis serviced at a reputable Freightliner Service Center.
Not cheap, but cheaper than road side service.
You end up with a solidly maintained RV out of the deal. A good Tech will educate you on what to look out for and existing potential issue.