I have a 2000 Patriot with a 330HP Cat engine. While climbing steep grades my coolant gets above 226 degrees and the "check engine" light comes on. The coach is lucky to get up to 25-30 MPH. After spending a great deal of money to have the radiator pulled out and cleaned there has been very little change. I am pulling a Jeep Liberty, but I would think the engine should be able to handle that easily. Has anyone else had this experience? Any suggestions?

Are you manually downshifting or letting the trans do it's own thing? The Allison trans doesn't know the engine is getting hot on a hill so you must manually downshift to a lower gear so you are at about 2100rpm.  This moves more air through the radiator for better cooling. We had a flyer from CAT about this when we owned our 1998 Beaver 300hp  Monterey.  Hope that helps. Marty

Does your coolant tank have a leak (maybe very small) per my mechanic that can cause loss of pressure in the coolant system thereby causing things to over heat.  Just a thought.

Thanks Marty. I will be heading out of Las Vegas tomorrow AM and will give that a try.

Did they check the operation of the radiator fan when they cleaned the system?  Leah's right, in that some overflow tanks are prone to developing leaks, air or fluid, which could be a problem.  Has the cap been checked for proper seating and pressure?

Hey, Gerald - does the fact that he can't get up more speed indicate a deeper problem?


-Joel

Make sure you downshift enough to maintain 2000-2400 RPM when under load.

Thanks for everyone's input. I do believe the system was checked out fairly well but you never really know. Thanks again.

I owned a '98 Patriot 330 CAT.  These steps taken by Beaver helped.
a. Place a hose extension on the engine blow by pipe to route the oil fumes back past the radiator.  This keeps the front of the radiator cleaner.
b. Install a smaller pulley on the fan to spin it faster.
c.  Replace the 5 blade fan with a 9 blade to move more air past the radiator.

When I changed the transmission oil from Dexrtron to Transend, the temperature of the transmission and engine dropped 20 degrees because they are in the same case.  The next time you change the transmission, consider Transend.

When climbing hills, keep the RPMs up around 2000 to circulate the coolant faster.

The CAT is smarter than we are.  It degrades at 225 degrees and shifts you to 3rd gear and limits the speed to about 35 MPH for about 10 minutes to give you time to slow down and increase RPMs and cool the engine.  If you do not take action it will stop entirely.  So if it happens again get over and slow or stop with increased RPMs until the coolant gets below about 218 degrees or you may end up stopped in the middle of the road.  I have experienced this a couple of times.  Luckily I stopped before it shut down.

Larry

Thanks, Larry, for adding that info.  I don't have a 330, but I'm sure that, like me, a lot of BAC members will benefit from such spot-on input.

I had a 2005 Patriot that experienced similar problems overheating.  After chasing the  issue for two years, changing expansion tank, replacing Turbo intake hoses, changing thermostats etc.  We found the problem was the wrong motor on the fan.  By taching the fan we found it was running at about 1/2 speed and was not the correct motor.  After replacing with the proper fan motor, all went well.