akghound

We are using coolant heat exchangers to pre-heat wash water for pressure washers on trucks. During cold weather these cool the engine to the point that the thermostate never opens. The mechanic tells me that when the coolant drops to somewhere below 130* the on board computer adds fuel to warm up the engine. The engine is set to run at 1000 RPM while washing, to power the pump via PTO. My question is how does the computer add fuel without increasing RPM. These are International 366 engines. I claim he is mistaken. It does add fuel at an idle at lower temps, thus increasing RPM but at 1000 RPM I doubt that any additional fuel is added to warm the engine. Can anyone please weigh in on this discussion?
Thanks .... Ken Gardner

wannadiesel

It could be playing with the timing a little to keep combustion temps up.

Have you guys thought about an exhaust brake with an idle warm-up mode?

Riflemanusmc

Do you mean DT466? The way the ECM adds fuel is by coolant sensors and air intake temp senders. Your dealing with a PTO and running them faster does not make them pump more. 1200RPM is about most of the PTO's pumping limit. An E brake will only work on an ECM controlled engine if you rev it up and then back off of it. Stand on it back off it. Time and time again, till it builds heat in the engine. I now of no OTR trucks E brake that you can manually close to build heat in the engine..

wannadiesel

PacBrake has a warm-up mode.

http://pacbrake.com/PDF/L5914.PDF

Riflemanusmc

466's don't have a pac brake on a fleet truck..

wannadiesel

Right, that's why I suggested they look into adding them. If they need to keep coolant temp up, running the PTO with the exhaust brake engaged will do that quite nicely.

Riflemanusmc

Sorry WannaI see what you were trieing to say now. And I concure..It won't happen though. Fleet trucks, they don't care about the drivers...