We have an 08' IC/CE Maxxforce DT that will not build heat. The driver complains that they are cold.
The grille has been covered fully with a winter cover, the coolant flushed, new thermostat, and temperature sensor replaced.
If you take it for a run on the highway it will build up to about 180F Max, and when you bring it back and park it (at idle) the temperature starts dropping and goes down to about 150F. It could run outside for an hour and still only stay at 150F.
The bus doesn't seem to want to build any heat, any ideas? There are no codes showing.
Coolant temperature sounds like normal diesel operation to me.
If driver is cold; Are the heater control knobs functioning properly? Knob rotated to driver heat? All heater valves open under hood? If there is a shut off valve behind rubber flap to left of brake pedal is it fully open? If bus has a booster pump is it functioning? Have there been any mods to the OEM heater plumbing?
No changes to the OEM heating system, the booster is working. I'll check with the boys at the shop and see if the control knobs were checked. It's nice to know that the temperatures are normal. I guess with the full winter cover we expected it to be around the 200F mark on the highway. Thanks Fastback! I'll pass this along to our mechanics.