Re: OVERHEATING ON 1997 WITH C8.3 CUMMINGS ENGINE
Reply #76 –
Something else to keep in mind is the location where the coolant temp sensor is positioned in relation to the hottest internal engine surface. Generally the sensor is far away from the upper cylinder liners. So why do manufacturer's derate at 220 deg F? Probably because the coolant temp at the cylinder liner is much higher and risks localized vaporization. We know that a 50/50 concentration of EG and Water will boil at around 260 deg F with a pressure cap of 15psi. Do the manufacturers allow 260 deg at the cylinder liner? Probably not. Manufacturers need to back off to a lower temp at the cylinder liner, something like 230 deg F. This gives a margin of safety for unknowns in the real world, unknowns like the condition of the owners coolant, cooling system, radiator cap, scale inside the coolant system and engine coolant passages, and even insulating crud and scale on the coolant temperature sensor itself. Remember, Bob is primarily talking about running customer's brand new equipment up 17 mile Baker grade, sometimes under the watchful eye of the OEM. Is this is something we want to recommend for someone's older motorhome. I'll let you decide.
Thanks Bob, I truly do appreciate your input and I take you for your word. No offense, just trying to shed a little insight into the workings of the system. 
Thanks Gary Bouland, I really do like the Foretravel brand. It's another great American Icon.
David Brady
'02 Blue Bird, Wanderlodge, LXi, NC
Points well taken. The customer asked me to do his new ored. Wanted to play motorhome engineer I guess after I mentioned the factory testing. Cat and Oshkosh needed the duplicate testing to verify the engineering on a seperate coach. Not hot enough in Wisconsin
I had more than one new coach customer that had me take their coach out to break it in. Used a travasack instead of their bedding and was very careful.
I drove every new coach that came in personally and fixed everything before displaying it.
Foretravel finally went to a marketing final where someone there did the same thing and fixed all the stuff prior to shipping by 1988 or so.
Came in deliverable basically.
Bob
Took all the used coaches out as it was a better way to resell them(fixed).
Yes i noticed the sensor location is a variable that did alter the readings on some builds.
Topic: OVERHEATING ON 1997 WITH C8.3 CUMMINGS ENGINE