Overheating Engine??

[mycoolbeans]

The issue: Driving a 2004 Winnebago Journey, 36 ft. with Caterpillar 330 engine, Freightliner chassis, pulling a Honda CR-V. A week or so ago, I was returning to Pennsylvania from a weeks sojourn down south. Coming into Pennsylvania, on I-70 E, I had an uphill climb of about 10 miles on a stretch that is known as Town Hill. At the top of the hill the descent is 9 miles to Breezewood, Pa. About 3 or 4 miles into the climb, I noticed the "check info center light come on. Trying to see the "info center" in my motorhome is impossible, so I scanned the gauges on the dash and noticed that the temperature guage was practically at the top of the guage in the red zone. Temperature outside was 95 degrees farenheit, I was running both the chassis air, and the house air (via the generator). I shut both of these down immediately and I pulled off onto the shoulder, walked around the rig looking for coolant leaks or anything else that would cause the overheating situation. Not able to see any visible leaks or steaming, I was in a quandry about what to do. I waited awhile (15 minutes), restarted the engine. The temperature had dropped below the mid range point on the guage. (I tried to call Coach Net for assistance but was in a dead zone where I could not receive calls). I then proceeded to drive up the hill. Gained about another 2 miles or so, and the guage again went to the top hot portion. Pulled over again, shut down, and waited awhile. Needle on guage dropped below halfway again. Started up, made the top of the steep hill, guage climbed into upper hot range (almost to top of guage). Stopped, did not shut off engine, and I noticed that the needle on guage dropped below halfway point. Now I was on a downgrade and eventually running on level road. As long as I was not climbing, the needle on the guage stayed below the halfway point. (I did not turn on either air conditioner during the rest of the drive home.) To make a long story short, we stopped for about 45 minutes at a rest area on the Pa. turnpike, and then proceeded home. I had another steep mountain to climb and another hill, but I managed as described above to baby the rig all the way home. After I got home and the engine cooled, I checked the coolant level which was fine. Today, I took the motorhome to a Freightliner service center. They checked for codes that indicated an overheating problem and found none. I was asked to indicate what lights came on at the dash indicating a problem, and as I said, the first indication that I had was a "check info center light". The service manager asked if the "check engine light" or "stop engine light" in the bar on the instrument panel came on. They did not. At this point, the service manager, based on what the technician found, and lack of codes, said that he did not think that I had an overheating issue. He suggested down shifting on a long climb. I was able to track temperatures during my experience on the various climbs where the needle was at the top portion of the guage and the highest temperature that I saw was 208 degrees, going to 202 degrees, and on the level about 198. Today, when I traveled over and back to the Freightliner center, I did not experience the needle climbing to the top part of the guage. (45 miles over and back). However, there were no significant hills of any type. Even though the Frieghtliner service center didn't find any problems, I'm still very apprehensive about this issue. This service center works on Cats and Cummins, and I believe they know what they are doing. Nonetheless, if anyone in the IRV2 forum has experienced an issue of this sort, I would be happy to receive any and all advice as to how I should proceed, and if I should be alert to something else that should be checked out. Sorry for the long thread. Thanks for your help.

[sip]

I have not had mine long enough to have had that experiance.I do know that when ever you have a over heating problem you turn up the engine heater to the cab on high, the water heater from the engine and anything else that heats from the engine. This allows another heat source to drain from the radiator. It has worked for me on trucks and cars, but makes it dam hot in the cab.

[CaptBill]

I don't think it's a good idea to immediately shut the engine when you pulled over. Instead, I believe it would be better to pull off, set the brake, and put the engine on fast idle (use the cruise control to bump it up to 1000=1100rpm, With no load on the engine, and the cooling fan moving air through thr radiator, I think it will bring the temp gauge down sooner.

The reason for the over-temp may be that the radiator needs to be cleaned. There are lots of threads on how to do it, and it's something that shouldbe done, probably at least once a year. Have you done that or had it done lately? The other issue may be the thermostats and anti-freeze dilution. Might be time to have a complete coolant system service.

[TomE]

Capt bill is on the right track. More than likely, your radiator is clogged by the "blow-by" from the crank case breather tube. This is a known problem with our FL chassis and CAT engines. There is a kit that FL sells that extends the tube or you can make one yourself- pretty easy. But first you have to clean the Radiator and the Charge Air Cooler. Call FL and they will guide you thru the use of Simple Green and a garden hose to clean the accumulated debris(oil).
E-mail me if you want more info. I had the identical problem.
Good Luck

Tom

[mark293]

Your experience is Exactly what I experienced going west on I-70 from Denver to Breckenridge. Take the others advice. Clean your radiator and keep the rpms at 2k. My next purchase will NOT be a rear radiator configuration.