sharp21

So I just got home after 7 weeks of work & finally get to drive my new first gen! Its pretty cold here in Alberta right now, but if she is plugged in she fires at first crank. The dually doesn't have any trouble in the snow either.
This is my first diesel & ive received some mixed info on a few driving subjects. First, warming it up. Is it okay to go warm it up for 20 minutes first, or am I supposed to start er up & get going (gently) until she is warm?
Second & kind of related; lots of guys leave their rigs running for hours, like when they are at the bar, er, out xmas shopping... In some extreme cases I know guys that leave their trucks running all night. I wouldn't think this would be appropriate, but you see the big rigs running all the time... What's the scoop on this?
Last, I have a high idle lever in the truck. In what situation would I use this?
Any other tips would be appreciated.
S.

77machomopar

High idle lever should be used for extended idling times like over night running. I always let mine idle in the mourning when its cold out for about 20-30 minutes. When its warmer outside ill let it idle for 5 or 10 minutes and then drive gently till fully warmed. I am sure others will say different.

sharp21

Thats what I thought for the high idle...
Does it follow that you are supposed to "start up & drive" at first because the low idle speed doesnt generate enough initial engine heat?
S.

ofcmarc

It won't generate hardly any heat at idle. But warming the tranny isn't a bad idea either. 20-30 minutes is a bit excessive unlless it's really cold (-40* or worse). Even at -20* I'll only run mine for 10-15 before I take off. It won't get warm till you drive it.

archer39

idling for 20-30 mins at your normal speed idle is bad. i let mine warm up for about 3 mins (the coldest it gets here is around 0 F and that not often) then just drive nice and slow. if you need to let it idle for an extended period of time make sure you bump up the idle.

BearKiller

Use the hand-throttle and bump the idle to 1200-RPM or there-abouts for any any idling period over a minute or so, hot or cold engine.

This also keeps the oil-pressure up and stirs up the transmission-oil.


Also, don't run up to the curb and immediately flip off the engine; let it idle until the pyrometer drops below 300* (about three minutes if you don't have a gauge).


If yours is the factory-supplied hand-throttle that works the foot-pedal, it helps to use the foot-pedal to set the idle, then pull the cable against it, holding the setting.

Most of that kind don't work so well by just pulling on the cable.



Big trucks sometimes idle for days with no obvious issues.


Huge locomotives idle at around 300-RPM and max at about 900-RPM; they often run and idle for years without ever being shut-down.

schamran

See if you can find yourself a winterfront that snaps to your grille. cardboard works too, but a winterfront helps in combination with a throttle lock to warm the truck up. I let mine run up to 20 minutes with the defrost on high. The tranny isn't warm, but you don't have to freeze on your way to work.

sharp21

Ive got the winterfront on.
Thats a good tip about warming the tranny. Also about letting the pyro cool before shut down.
S.

Jet100

Most Tractor trailers have a high idle set around 1000 rpm's. Mostly to stop what we call "wetstacking". Also to help keep the engine warmer in cold weather. Wetstacking happens at low idle, when there's not enough exhaust pressure to blow oil and soot out of the stack,to keep it dry. Can ruin valves.

Richie O

Sharp, your 727 auto will not cycle tranny fluid if in park. Must be in gear or nuetral for oil to flow. I always start engine, let oil pressure come up, set brake, put in nuetral, set idle to 11 or 1200. 4 or 5 min is fine. Just make sure you baby the thing till temp comes up. No high rpm's or full throttle till things are warm. Low idle on a cold day is bad. 5 min max low idle, can get away with longer when its warm out. Just be carefull. I had a truck on high idle for 1/2 hour or so and I got in and backed up in my driveway and the alternator siezed up and broke the belt off. If it had happened 10 min earlier I would have been in the house and not heard a thing. It would have ruined the engine for sure. Thats my opinion.

Crossy's son

Yea RichieO is right when we had our 727 truck, until we put the shift kit in it ,if you warmed it up in park it would barely move when you put it in gear. The transgo we put in it filled the converter and cycled fluid in park. It was like 80$ i think and a days worth of work.

Bob Beauchaine

If you have an exhaust brake you can engage it and your truck will warm up quicker also.

Bob

92roughstock

if I plug in the block heater, I drive it like a summer morning- just get in and go. If I didnt plug it in, I kick the idle up with a rock on the accelerator, and let it go for however long it takes me to eat breakfast (3-5min). Windshield is clear, and cab is toasty. I dont like to idle for any longer than that, as it increases the likelihood of cylinder washdown caused by super low combustion temps, and tends to coke up the injectors (again, combustion temps). For an automotive deisel, idling will kill it faster than overworking it.

If the oil pressure is up, and the body isnt creaking and groaning too bad, you should be ok to hop in and go, almost like a gas rig. Just go moderate on the throttle til it reaches operating temp.

I'll second Bearkiller's recommendation to let it idle some to cool down- esp for the turbo's sake.

abachar

I was told to do this by the guy I bought my 91 from. He told me to let the gauge drop to 300 then shut it off. It was a while ago, but he mentioned something about the preventing the exhaust manifold from cracking.

What exactly does this cool down do? I still do it even though the 93 has no gauges, yet.

wannadiesel

It allows the turbo to cool down and prevents oil from coking inside the turbo.