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Topic: Exhaust brake question. (Read 528 times) previous topic - next topic

Exhaust brake question.

We've got a "Pac Brake" on ours, and in researching it for a forum member I came on a quote I'd never seen: anyone else have a PB and does this work? If it does, it sure beats fooling around with the block heater.  ^.^d

"The Direct Mount features a built-in "warm-up" position that will help your engine warm-up in half the normal time.Turn on your Pacbrake, set the idle speed and say goodbye to white smoke and hello to a quicker and safer cold engine warm-up."

1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
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                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
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                        Full-Timers 'Sailing the asphalt sea'

Re: Exhaust brake question.

Reply #1
Mike,

I am not aware of any RV that uses the exhaust brake (closed) to speed engine warm up. You can check with PacBrake, it may have something to do with the wiring through the Allison ECM.

And, while it would speed warm up, it would have no affect on starting ability in cold weather.

Guess one could run an additional wire direct to the exhaust brake solenoid and use diodes to wire this function.  But, the danger would be leaving it in that position when you start to drive. That would lead to severe exhaust manifold overheating and very low power.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Exhaust brake question.

Reply #2
I am not aware of any RV that uses the exhaust brake (closed) to speed engine warm up.

Thanks Brett, I thought that line (in the Pacbrake cut sheet) was interesting, never heard of it before. Plus, for us "old and in the way" types, there would have to be a "beep beep beep" warning to avoid driving out with the switch on! :-[
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'