Community Forums

Mekanic · 12-01-2013, 04:47 PM

Quote:

Originally Posted by Belgique

....... I don't think the fan was kicking in because it was too quiet! Dry weather...no rain. Just checked and I have not changed coolant (about 37K miles) but the manual says 100K. The Thermostat is probably worth a change. Is that a DIY thing?

So you think it's the fan so your going for the Thermostat??

I also think you take the engine temp with a infared gun before jumping to the checkbook to get your parts. REad more on here

Quote:

Originally Posted by jamesrxx951

........ If the gauge was showing hot but you did not hear the cooling fan engage, ...... It may also be necessary to measure the actual engine temp with an IR gun close to the cylinder head temp sensor and compare that reading to what the scan tool is reading the actual temp at. ...... but it may also be the sensor failing when it reaches that specific temp range. Have seen a few CHT's fail in the past on other vehicles.

I'd really see how hot it is (with the infrared gun)before jumping to parts changing.
I would suspect the Fan clutch before the thermostat.

jamesrxx951 · 12-01-2013, 05:04 PM

Quote:

Originally Posted by Mekanic

So you think it's the fan so your going for the Thermostat??

I also think you take the engine temp with a infared gun before jumping to the checkbook to get your parts. REad more on here

I'd really see how hot it is (with the infrared gun)before jumping to parts changing.
I would suspect the Fan clutch before the thermostat.

I did not recommend any parts changing. Just possible causes but explained a quick diag path to determine what direction to proceed with. You need to have an overheating radiator to get the cooling fan to engage. These are not electric or electromechanical cooling fans that are PCM controlled. They need the heat from the center of the radiator blowing onto the hub directly to engage the clutch. The engine can be melting down and the radiator is cool and the fan will never engage fully.

Belgique · 12-01-2013, 08:09 PM

Thanks Mekanic and James. I'm not skilled at this stuff so the only thing I was even contemplating was a thermostat since they are cheap and if it was easy. I'm a leave it to the pros kind of guy. I just had a Jeep problem where it would not throw a code and the garage could notmake it happen there. Finally we got a code and they fixed it. My goal is to gather info so the garage can fix it without having to drive us and the animals up and down hills. Success would be if we can make it happen and report what we find and they fix it while we wait.

Sincerely appreciate your counsel.

onecb · 12-03-2013, 11:55 AM

You may want to go here and read what the TSB says: 06-21-15***MIL ON - DTC P1285 / P1299 - 5.4L 3V / 6.8L 3V - FALSE OVERHEAT
I had the same problem with mine at 22000 miles. Had this procedure done and not a problem since. Alvin

jamesrxx951 · 12-03-2013, 02:29 PM

Quote:

Originally Posted by onecb

You may want to go here and read what the TSB says: 06-21-15***MIL ON - DTC P1285 / P1299 - 5.4L 3V / 6.8L 3V - FALSE OVERHEAT
I had the same problem with mine at 22000 miles. Had this procedure done and not a problem since. Alvin

He said his motorhome was a 2008 model. However it would possible apply if his chassis is an 07 on an 08 build coach.

Tiny Dog · 12-08-2013, 01:18 PM

If you did not have the sound of an airplane preparing for take off from under the hood you need to check the operation of the fan clutch.

Belgique · 12-08-2013, 02:07 PM

I didn't and that's what I'm guessing. The fan works at idle speeds, I can feel the flow. On the interstate it didn't do that roar. I have a garage appointment Tue. I'll report back for the benefit of folks after me. Thanks!

jamesrxx951 · 12-08-2013, 02:17 PM

Quote:

Originally Posted by Tiny Dog

If you did not have the sound of an airplane preparing for take off from under the hood you need to check the operation of the fan clutch.

After it has been verified that the engine is truly overheating and the radiator is not plugged directly in front of the fan clutch.

chboone · 12-08-2013, 11:39 PM

Listen to what James is suggesting, he's a Master Mechanic at a Ford dealer. Verify the actual engine temperature before starting to change parts. The V10 is not known for having overheating problems. Have you used a very bright flashlight to verify the radiator is clean, especially between the AC condenser and the radiator. You may need to lock up the four legged kids in the bathroom or bedroom while the dog house is open.

Chuck

Belgique · 12-09-2013, 06:31 AM

Folks! I recognized my inadequacies on engines at about the second post and found a trusted garage where we are now. I have an 0800 appointment to fix it tomorrow (Tue). No way could I even begin to diagnose what's going on or fix it if I did. You kind folks helped me confirm that I wasn't missing anything obvious. I'll report the results ASAP.

And yep, dogs and cats have been warned that they will be imprisoned.

jamesrxx951 · 12-09-2013, 08:34 AM

Quote:

Originally Posted by Belgique

Folks! I recognized my inadequacies on engines at about the second post and found a trusted garage where we are now. I have an 0800 appointment to fix it tomorrow (Tue). No way could I even begin to diagnose what's going on or fix it if I did. You kind folks helped me confirm that I wasn't missing anything obvious. I'll report the results ASAP.

And yep, dogs and cats have been warned that they will be imprisoned.

Check the build date on the chassis also (not the coach). That TSB that was talked about above may be what you need.

Belgique · 12-09-2013, 05:47 PM

I checked the VIN and mine is an 07 build. I'll mention this to the shop tomorrow. The TSB says it throws a code...mine has not so maybe it is not but worth mentioning to the folks. Thanks.

toneumanns · 12-09-2013, 05:53 PM

Quote:

Originally Posted by Tiny Dog

If you did not have the sound of an airplane preparing for take off from under the hood you need to check the operation of the fan clutch.

That is the truth. Mine has only engaged 2 times but when it did there was no mistaken it. First time I thought we were preparing for take off. Must move a tremendous amount of air.

jamesrxx951 · 12-09-2013, 06:00 PM

Quote:

Originally Posted by Belgique

I checked the VIN and mine is an 07 build. I'll mention this to the shop tomorrow. The TSB says it throws a code...mine has not so maybe it is not but worth mentioning to the folks. Thanks.

You have to remember the PCM will not set a DTC unless the over heat threshold is reached. I believe it is around 275F. Don't remember the exact number. However if it was caught prior to the set point, no DTC will be set. I was going up a steep grade with my V10 Class A, 1st gear, WOT, and 2nd gear WOT, my engine coolant temp never went over 205. So it was working hard and the fan never was heard.