Re: [A/S] Two questions

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Tom,
  If the water tank is in the front and if his trailer is a bit 
tongue-light to begin with, he's doing the right thing. That's 2 "ifs".

It is NOT recommended that you leave your Diesel P/U idling for long 
periods. My Dodge manual even specifies 5 minutes as the maximum idle 
time. There are several reasons: it wastes fuel, the injectors tend to 
carbon up on the tips, and you can get incomlete combustion because of 
cool cylinders. The very large trucks aren't bothered as much by these 
points, and the drivers often leave them idle so they have heat or A/C 
while resting/sleeping in the cab.

One exception to the "no excessive idling" advice: when you pull off the 
highway on a hot day, especially when you're towing, keep the engine 
running for a few minutes, preferably at a fast idle (1000 RPM) to allow 
the oil and turbocharger to cool down a bit. If you come into that rest 
area at the top of the mountain, stop next to the trucks and shut 'er 
down for lunch in the trailer, your turbocharger will sit there and cook 
the oil in the bearing. You probably won't notice a problem this week, 
but you'll pay the bill eventually, and it's not cheap. Allowing the 
engine to idle for 5 minutes will let the coolant and oil drop off in 
temperature and allow the turbo to cool off somewhat. Your exhaust 
pyrometer (you do have one, right?) will fall to 300 degrees or so. If 
you fail to allow a cooldown, note how the pyro RISES as the truck sits.

Also, ALWAYS allow the engine to drop to an idle for a few seconds 
before shutting off the key. If the engine is revved up, the turbo is 
spinning faster, and will coast for a longer period with no lubrication. 
For the same reason, refrain from jazzing the throttle after startup 
until the oil pressure has stabilized for a few seconds.

                          <<Jim>>