Ok all you Cat guys, after about 3hrs I loose the boost and no power up hills. All pressures and temps are fine. New fuel filter. It did this to me on my trip from Ky, We couldn't find anything. When it sits overnight it gets it back. Heat related? We are at a loss. Tom

Have you been to: http://autos.groups.yahoo.com/group/CATRVCLUB/

No but I just joined thank you very much. Tom

Sorry I didn't respond sooner - I haven't been keeping up with the forum...

If you have an electric shutdown plunger I would check that. If it is an air shutdown plunger then all should be good. The electric plunger retracts with key on power. If the plunger is getting weak it will slightly apply and keep the governor from going to full power.

Roadway Express had a bunch of Ford Tractors with the 3208T and 3208NA cat in them. If drivers complained of low power after running it for awhile, and all others suspects had alibis, we would change out the Shutdown Plunger - this usually cured the problem.

Have you been following the thread on the lower sulfur diesel fuel? This could also be an indication of impending injection pump failure.

Sorry too Bill, I've been on the road. I have an air shut down. We are about to the point of yanking off the pump and rebuilding it. We have also replaced all fuel lines installed a racor and checked the pickup in the fuel tank. We just thought of cracking the return line to make sure it is acutally returning fuel.Thanks for in info. Tom

I have got to tell you when Bill tells you something about a Cat you better listen. I do have a electric shut down, replaced it today, took it for a ride. If you have ever been over the Sky Way bridge here in St Pete Fl you will understand me being so happy to only loose 8 mph going over and only 6 mph on the way back. Three Cheers for Bill. Thanks again Bill. Tom

You're welcome. I am glad you posted the outcome.

Most any diesel engine with an injector pump can suffer from low power because of a weak shutdown solenoid. The solenoid does not shut off the fuel. It turns the governor off thru a mechanical linkage inside the injector pump.