Overheated..

[HoleInOne]

On my return home from Florida we had only been on the road about an hour and I started losing power. Checked the guages and temp was 220. Pulled over and checked the coolant level and it appeared low. Put anti freeze in and proceeded down the road. After a couple of more hours temp started to rise again to 220 degrees no more no less. Pulled off and got in touch with a mechanic down the road. Drove to the next exit and he checked everything and suggested a new water pump. I didn't have a lot of faith in his diagnosis by looking around his shop. I paid him for his time and contacted a CAT dealer who was just up the road. Upon arrival they checked it out and said the water pump was fine and suspected the T-stat or serpentine belt or air filter could be the problem. Radiator and fan checked out fine as well.
After replacing the suspect parts I was on my way. About 45 minutes down the road .....same thing 220 temp. I called and they said bring it back and they could put it on the dyno for further testing. Once they did that it showed up that the fan would not come on. They unhooked the fan control module and allowed the fan to run constantly and the problem was solved.
I drove home that way and did not have ant more problems.
Questions:
1) Do I need a three speed fan?
2) Where did CC get the fan modules?
The CAT dealer said the fan, radiator and controls come from the chassis builder (CC) and I should contact them for the replacement. Before I do that I just thought I would run this by the forum.

BTW my 400 hp C9 made 305 hp to the wheels. They said that was pretty good.

[palehorse89]

Till others chime in to help with your question, here is a thread that just might answer your questions with phone numbers to call also http://www.irv2.com/forums/f112/radi...on-170550.html

[BFlinn181]

Letting the fan run at full speed all the time will result in lower MPG.

[phays]

You could have a bad fan controller or bad sensors for the fan controller. I had the same problem and was fortunate and had bad sensors. You could hook the fan controller back up and turn your dash a/c to max and that should force the fan to high speed once pressure builds at the a/c compressor.

Counting the pressure switch an the a/c compressor, there are three sensors. Of the other two, one is for engine coolant temperature and the other for the turbocharger air temperature. The two temperature sensors can be tested with an ohm meter at the fan controller plug. In my case they both showed an open circuit.

Running you fan on high will result in lower fuel mileage. Lots of info on the Yahoo Country Coach Owners forum on this problem. They have a very good write up in their files section and I would advise you to go there.

If it is the fan controller, you will need to pull it out and get the serial number as the controller is programmed for your particular engine setup.

[dons2346]

"If it is the fan controller, you will need to pull it out and get the serial number as the controller is programmed for your particular engine setup."

You need the part number and not the serial number. Programming for the Sauer Danfoss fan controller is part number dependant

[Mekanic]

Shame you had to pay for the New T-stat, serpentine belt and air filter you really didn't need.

[chuckinthebus]

Originally Posted by HoleInOne

On my return home from Florida we had only been on the road about an hour and I started losing power. Checked the guages and temp was 220. Pulled over and checked the coolant level and it appeared low. Put anti freeze in and proceeded down the road. After a couple of more hours temp started to rise again to 220 degrees no more no less. Pulled off and got in touch with a mechanic down the road. Drove to the next exit and he checked everything and suggested a new water pump. I didn't have a lot of faith in his diagnosis by looking around his shop. I paid him for his time and contacted a CAT dealer who was just up the road. Upon arrival they checked it out and said the water pump was fine and suspected the T-stat or serpentine belt or air filter could be the problem. Radiator and fan checked out fine as well.
After replacing the suspect parts I was on my way. About 45 minutes down the road .....same thing 220 temp. I called and they said bring it back and they could put it on the dyno for further testing. Once they did that it showed up that the fan would not come on. They unhooked the fan control module and allowed the fan to run constantly and the problem was solved.
I drove home that way and did not have ant more problems.
Questions:
1) Do I need a three speed fan?
2) Where did CC get the fan modules?
The CAT dealer said the fan, radiator and controls come from the chassis builder (CC) and I should contact them for the replacement. Before I do that I just thought I would run this by the forum.

BTW my 400 hp C9 made 305 hp to the wheels. They said that was pretty good.

Did they credit you for parts replaced that didn't fix the problem or at least, comp the dyno?

[Tim&Paula]

It will definitely lower your mpg.

[HoleInOne]

Originally Posted by cnkinthebus

Did they credit you for parts replaced that didn't fix the problem or at least, comp the dyno?

They comped the dyno. Belt and air filter needed replaced.

[HoleInOne]

Finally broke down and ordered the new module after replacing the sensor. Now before I take the old one off, is there gonna be oil running down my elbows? Also do you need to bleed the system after putting the new one on? Anybody ever replaced this?

[Peralko]

Have you rechecked your coolant level? A friend of ours thought he had an issue with the fan controller. When he started the engine after disconnecting the fan control module, I noticed a coolant return hose was leaking--it was rubbing on the AC compressor. Replaced the hose and put 9 gallons of coolant in the system, and no more problem!

[courtjester]

Originally Posted by phays

You could have a bad fan controller or bad sensors for the fan controller. I had the same problem and was fortunate and had bad sensors. You could hook the fan controller back up and turn your dash a/c to max and that should force the fan to high speed once pressure builds at the a/c compressor.

Counting the pressure switch an the a/c compressor, there are three sensors. Of the other two, one is for engine coolant temperature and the other for the turbocharger air temperature. The two temperature sensors can be tested with an ohm meter at the fan controller plug. In my case they both showed an open circuit.

Running you fan on high will result in lower fuel mileage. Lots of info on the Yahoo Country Coach Owners forum on this problem. They have a very good write up in their files section and I would advise you to go there.

If it is the fan controller, you will need to pull it out and get the serial number as the controller is programmed for your particular engine setup.

any chance you can elaborate on that continuity test for the sensors? I think the one plug in that I see at the fan controller is a three wire plug and I think goes to the coolant temp. Where do you read the open circuit?

I'd like to be sure before I start getting parts, although Kevin believes its the temp sensor.

thanks

toni

[colo.kids]

I am dealing with the exact same issue (overheating) and have found by testing the 3 sensor circuits that the water/radiator sensor is bad. I found the following how to on the internet for the diagnosis though mine is a Cummins and your Cat might be different.

1. The fan should come on in the HIGH SPEED setting on cold start up and slow down as the engine warms. I do not think it does this?
2. Also, the fan speed should default to HIGH when the dash AC is placed in MAX mode. Again, I do not think it does this.
3. The fan sensors can be tested using the following instructions.

Take the following measurements with Ignition OFF and Engine COLD.

Climb under coach and disconnect the 6 Pin Fan Controller Connector. It has a "latch" on top of connector you release and hold open while pulling connector apart.

Wipe connector clean so that you can see the alpha markings ABCDEF denoting wires/pins.

The following measurements are taken on the Engine Side of the Connection not the Controller Side.

Wire/Pin A&B go to your Dash Air Conditioner Relay
Wire/Pin C&D go to your Engine Coolant Sensor
Wire/Pin E&F go to your Air Temp Sensor

With Multi-Meter set on OHMS

Measure across C&D should = 1.2K to 3K OHMS
Measure across E&F should = 1.2K to 3K OHMS


I just received a replacement water temp sensor from CC (great folks to work with BTW) and now ready to do the install.

The sensor (I think) is located at the bottom of the radiator, so now I wonder how to replace without draining. I am thinking if I am quick I can minimize the amount lost, catch and recycle what I can, and not get too covered with coolent .

[Southpark]

I'm glad you posted HoleInOne. I've read about these issues and fixes (and attempts at fixes) before. But I'm not sure I've seen a repair place come through narrowing down the issue by putting the coach on a dyno. I will absolutely remember that for the future. And unless I missed it please post the name and location of the CAT service center. I'm beyond expecting any place to be 100% perfect in their diagnostic abilities, but still expect to be treated fairly. The business comping the dyno strikes me as trying to play fair. Thanks