At the pump - let it run or shut it off?

[Bill Stockard]

I let it idle at the pump--keeps the weenie dog cool in the summer and warm in the winter!!



Bill

 

[redneckdr]

run or shut down??

i generally let mine idle til the EGT is down to an acceptable level, then shut her down. that way i can check the oil if i want to. also lock my baby before i go in to pay. i wouldn't want some low life to get a full tank, in additon to ONE NICE RIDE!!

 

[DieselB59]

I let it run, and have since I owned it. In NJ there is a law against self service, but the Hess station that I deal with knows me well enough not to say anything. They also have a diesel only island.

 

[Bigsaint]

I have an account at a local trucking company, so I fill it myself and always let it run. Usually, it's right after work, so I use this time as a chance to warm up in the winter months and just switch the ebrake on during idle.



Scott W.

 

[Lil' Dog]

Originally posted by Wirenut

has anyone ever experienced a "run-on" condition? I new that it could happen with natural gas but I didnt know it could happen with gasoline. I may have to go spill some gas and try this

I don't think you really do... The gasoline will make the engine run away like running on engine oil. Unless you can stall it with the gears you pretty much have to let it explode from over speed. This is not a funny thing at all.



The positive air shutoff that JHansen has is a large flapper valve installed in the intake tubing from the intercooler to the intake manifold. His is the fancy one that plugs into the ECM and measures engine RPM. . When turned on, if the RPM of the truck exceeds a setpoint of say 1500 rpm the valve closes and chokes the engine to shut it down. For the places JHansen goes, its the law and saves lives never mind the CTD and he can leave his truck unattended.



There are cheaper ones that have just the pull cable to shut the valve. Anyone who ran or owned a Detroit diesel, 71 or 92 series have seen these before.



J-eh

 

[JHansen]

Guess I should have added to my original post that I fuel exclusively at cardlock locations-generally I'm the only one around when I'm fueling. The location I use most of the time does have the gas pump right beside the diesel-but most of them have the gas pump far away to keep the 4 wheelers away from the "professionals"... . I never leave my truck while I'm fueling so odds of it getting stolen or having any problem are slim to none anyways.....



Lil' Dog hit it right on the head with the positive air shutoff. The Roda Deaco one that I run is actually a swinging disc so when it's latched open it's completely out of the airflow-I see a tick under 30 lbs. boost with my 275's and EZ so I'm pretty confident if it does restrict airflow it's real minimal... . Depending on the application they are either spring-closed or solenoid-closed. The spring-closed ones use either a manual pawl, air-tripped pawl or electric-tripped pawl to release the disc..... the solenoid-closed one (which is what I have) actually uses a big electric solenoid to swing the disc into place. When you clear the condition that actually caused it to swing (and clean your shorts out ) it's just a matter of swinging the disc back to the open position and you're ready for action again.



Mine senses engine RPM for automatic shutdown as well as having a big red manual toggle under the dash. The sensing deal is pretty neat-you tie into your alternator ahead of the rectifier bridge-the AC signal that is generated increases in frequency as the engine speeds up. So once you make the connection you unhook the butterfly, press the TEST button on the master box that makes it trip at 2/3 the selected RPM, bring 'er up with the throttle until you hit 2/3 of the speed you want, and turn the calibration pot until the light just goes out. To make good and sure you perform 1 more test at full speed and normal conditions to make sure it won't throw if you hit redline while racing a Duramax . I tweaked mine about 1/4 turn after the red light went out so I can be sure that it'll kick in before the engine explodes-but still let me have redline for dyno runs and things of that sort... .



I try to remember to test mine about once a month-just throw the switch with the engine off and make sure the valve trips. Good for peace of mind as well as being part of the rules of the 'patch!



Any more questions fire away!



Jason

 

[WileyCoyote]

Letting It Run???

Letting the truck run anywhere there might be gasoline fumes is a definite no no.



A few years ago, we had an 18 wheel transport unloading Avgas at our local airport. The operator let the tractor idle while he unloaded into what he thought was an empty tank.



Lo and behold the tank was not empty, and the unloading Avgas spouted out the vent system. The tractor "sniffed" the fumes and about a minute after the Cummins in the tractor ran away with itself, the whole thing lit off, trailer and all.



It used to be a well known taboo when oil bath air cleaners were used never to wash out the "horsehair" above the oil bath with gasoline. If you did, the fumes that stayed with the horsehair would provide enough fuel to cause the diesel to run away and fail in over rev. Not a nice site.



Caterpillar makes the statement: "Engine wear is proportional to fuel consumption. " Translation: If it is running, it is wearing.



I always shut mine off. All the rest of you should also.



Harry

 

[JyRO]

Turn mine off...

I turn mine off because I'm a cheap a$$! If that engine is not doing work (W=FxD, when there's no distance covered there's no work done), then I shut it off, cause I'm too cheap to let it just set there and waste fuel. Except when I'm towing and just pulled off the interstate and it needs to cool off. Then I generally shut it off 5 minutes after hitting the fuel station lot. That winds up being after I get about 10 - 20 gallons of fuel in it.



- JyRO