Overheating

[signet63]

Dear reader,

I just read some topics from 2011 on Overheating. I have a 3126 Cat engine in my 2000 Winnebago Ultimate Advantage. I am going to spray my radiator with simple green and use a garden hose to clean it. I will look at the slobber tube to see if this is the issue.

What I what to know is what is the correct procedure when the temperature light comes on and I am driving? Do I pull over and turn it off to let it cool? if so how long should I wait? Do I pull over and let it idle? Will the temperature fall if I do this? Do I need to give it Gas to keep the RPMs up to 2000? I do not know and asking for advise.

I just had an issue driving back to Las Vegas from Williams AZ. I stopped in Kingman and topped off the fuel tank and preceded the rest of the way into Vegas. I admit it was the hottest part of the day when I crossed the Pat Tillman bridge over the Hover Dam and climbing this hill my temp light came on. My phone said Boulder City was at the time was 115 Then an engine warning light just before the check engine light came on. Yes three different lights. The all went off as soon as I crested the hill going downhill and the temp went back to normal. The last 20 miles into Vegas my temp light would come on on each hill I climbed. something 7 more times. Last summer I had the temp light come on on the Baker Grade in California. The Temperature at that time was over 105 I remember. I just pulled over and turned everything off. I was not towing a toad at that time.

Thanks,

Bill Miller

[ziaptrn]

I have wondered the same in the past.
Before effecting a permanent fix by changing the fan clutch/fan on our 08 Journey with 350 Cummins 6.7L, I also experienced lights from overheating.

I never got to three different lights, however. It is my understanding that there is a sequence; 1st is high temperature warning, and 2nd is high temp STOP which throws a code. The first light alone does not leave a recordable code in the ECU. This is just my understanding, however, and may be incorrect.

As I moved uphill while driving, I could watch the temperatures rise. I understand that even as high as 210 degrees seems to me, that temperature is fine per Cummins. The light would come on at 215 degrees, and I pulled over.

At this point, I had the same questions as you, so I sort of split the difference. I was afraid to stop the engine completely and thus have no coolant flowing, so I allowed the engine to idle a few minutes. The light always went off after a short time - perhaps 90 seconds at idle. I then would shut the engine down after letting it run a bit more to cool off - which it always did while idling. I'm not sure if idling is the correct procedure, but I can say that the temperature always dropped consistently.

After walking the dogs or somesuch, I would crank the engine back up and proceed.

I did learn that if I geared down and let the engine run at 2100-2400 rpms (whatever gear was required to do this from 3rd or 4th), it would cool while running and I didn't have to stop etc., and the light wouldn't come on. The light typically came on when I didn't realize that we were heading up a grade or that cruise control was allowing the engine to lug and rpms to get down to 1500 or so (not an exact figure).

So - for future reference and barring something obvious like coolant spewing everywhere, in which case I would turn it off pronto....what IS the best practice?

Thank you for asking this question and helping my ongoing RV education. I'll keep an eye out for responses!