I have a diesel start up question...

[jaysm35a2]

I got into a discussion the other day with other "truckers" about starting their trucks and warming up.

Do any of you guys see a problem with walking out when its ,example : 65F outside temp ,getting to work and starting your truck in the morning and running it up to 1400 RPM right away after it show's oil pressure on the gauge to build air pressure and all?

I just don't do that for many reasons but I wanted other guys opinions on the matter. - Thanks

[1958 F.W.D.]

I don't give a horses fart if it's gasoline, diesel or propane powered....Or a lawn mower, my pickup, my antique firetruck or a locomotive.......I have been taught to start it, let it idle for a minute or two (the colder it is outside, the longer) in order to get the crankcase lube warmed up just a bit and establish and maintain the oil pressure.......And then let it rip.

The only exception is any 2-stroke green leaker- start it up and floor it to the firewall. But drain the crankcase oil all out first.

[jaysm35a2]

The guy I was arguing with said, he starts it, when it shows a oil pressure reading on the gauge then he runs it up to 1400 RPM to build air pressure and all.

[hatcity]

I just start it and leave it until the air dryer dumps.

Then I bring it to about 1000 and turn all the lites on (head, clearance, warning, flashers) and walk around with a hammer to bang the tires.

Then I put the lunch box in along with my book. Park the pick up and climb in. Then I check the signal lites work, brake lites, reverse.

By that time, the temp is up to about 140 and I am ready to rock and roll.

But that's just me

[farmer52]

What grade oil are you using? 15W-40? If your air pressure is low, you will actually be loading the engine as soon as it is started. Increasing the idle to 1200-1400 rpm AFTER you have stable oil pressure should be okay. Colder temps will require a longer idle time before increasing the speed.

[jaysm35a2]

He's using 15W40 Rotella In the truck Im talking about and its a older Cummins engine.

I guess he's ok to run it up to 1400-1500RPM once it shows oil pressure on the gauge at warmer temps.

I start my work truck , it runs itself to 900 RPM, builds air then after warming itself up it idles down to 700 RPM. After about 10 min or so I start out after a pre trip.

[j_martell]

I check oil, coolant, ps fluid, start the truck &turn on the lights (clearance/marker/ID) both sets of floods, the highs and 4-ways. Get out, check under the hood one more time, close the hood, check tires and lights, turn off highs, 4-ways and floods, then get dirty checking out the underside and roll off frame.....after all that (about 20mins), I'll turn the idle up.....this time of year it's at about 120* by then.

[Lmackattack]

I fire them up and let them idle until I leave the yard. My thought is Cold oil needs to thin out to better get into all the parts of the motor.

I always wondered why some generators would go to 2100 rpm high idle right from a cold start. That can't be good on bearings

[41chevy]

I was taught never start up and go. Everything gets circulating and start warming up. Like most larger diesel generators, I've put a three quart accumulator on my trucks so when the key goes on before start. The accumulator pre lubes the top end and turbo before you crank it up. Gets refilled and pressurizes after start up. Paul

[Dirtymilkman]

My trucks run a average of 38% idle time. Idling a diesel is not good for it. They'll slobber fuel and it washes the oil off cylinder walls. You wanna run it at least 1000 rpms to build cylinder pressure. A cold motor is worse. If you have oil pressure for 1 minute idle it up and do your pre-trip.

[gearhead204]

if you never want to RESTORE IT ,FLOOR IT!

I wait until I hear all cyl's firing then increase idle usually not more than 1100 rpm until I see temp gauge moving past 130 then will start whole truck moving after 130 but no HARD THROTTLE until eng is up to full temp only exception is fire calls when i'm in ,were GONE.

[1958 F.W.D.]

if you never want to RESTORE IT ,FLOOR IT!

only exception is fire calls when i'm in ,were GONE.

Nope, not even then. If I arrive at the station and I'm going to be the D/O I will start the rig, then go grab the printout, check the map for two hydrants, then go get my gear and stow it on board, then climb in and wait for everyone else.

If I am on a duty night, the rig was already checked out and is warm.

[fxfymn]

Idle fire apparatus before going on a call? 32 plus years and all we ever did was start it, wait for the crew to board in 15 seconds or less (or they got left), and try to go from 0 to as fast as the driver could make it go. Was it hard on them? Absolutely; but I personally never blew one up or heard of us blowing one up once we went all diesel.

That is one reason why fire apparatus gets replaced at very low miles compared to most commercial applications. 100 to 150K miles on a fire truck are much harder then the same miles on almost any other truck. In 100,000 miles a fire truck is probably started and stopped at least 6 or 7,000 times, with many of those going from dead cold to full acceleration in 30 seconds or less.

Wait for air to come up? That is why we kept any rig that had a reputation for leaking down on an air line from the station's compressor.

And remember the truck is stored in a heated building, so "cold" starts are not as cold as being outdoors in sub-freezing weather.

Most drivers did let them idle down before shutting down to let the turbo cool and properly lube.

[j hancock]

At 65 degrees, as originally mentioned, not a big deal but it is good to see a little water temperature indicated on the gauge before really getting after it.

[Bigdogtrucker]

I let every engine I own warm up a bit and cool down before shutoff.Doesn't matter if it's a Mack or single cylinder Kohler

[BGarofalo]

I have always let everything run for a bit before working the engine. I've noticed though gensets with big cummins and other diesels will just start and go straight to operating rpm under load regardless of whether it is 90 degrees or negative 20. They operate reliably with no ill effects...

[j_martell]

One farm I worked on had a 250kva genset powered by a cat 3406 that would fire and run straight to 1800(ish) revs.....but, when grid power was on, it had heaters that kept the coolant warm (120* on the read out) and the oil warm.......

[Quickfarms]

My truck will not build temperature idling in the yard! I start it, do the pretrip and let the air build. If I am in a hurry I will run it up to about 1000 rpm. On the road I baby it until it is up to temperature. After that it is hammer down.

[220cummins]

I always start it let it idle do a pre-trip then get in it and go. Even first few miles I'm easy on it because I let the gear oil in the rears and trans warm up. If you let it warm up it creates less premature wear on all the components. Rev a cold mack and it will swallow a valve. Just like everything its all good in moderation, not to much idle or not enough at which ever temp.

[mike69mackman]

Max idle on mine is 700 rpm. I check fluids and start it wait for oil pressure then idle up to 700 rpm and finish pretrip and paperwork then let it idle at that speed while I'm in the shop having a cup of coffee. I found that starting and letting it warm up a bit if something mechanical is gonna go wrong it'll happen during this time frame rather than starting and taking off after only a few minutes and calling the shop five minutes later saying the truck shut off etc. good habit to keep especially in the winter when cold weather related mechanical problems can easily pop up.

[gearhead204]

mike what the hell are you running that you idle up too 700 rpm? I didn't know any thing was suppose to idle lower than 650rpm.

just wondering - rob

[mike69mackman]

It's an isx motor that base idle is 500-525 rpm. Fastest idle is 700 rpm. We've had the laptop connected and changed idle settings but that only created other runnability issues, so we set them back to factory specs. Personally I'd like to fast idle at about 900 rpm but...

[james j neiweem]

Some Gen sets have heated water or oil. The big EMD.'s have a circulating oil pump that runs all the time.

.

[thomastractorsvc]

I usually pop the hood and check out the fluids,belts and stuff after looking it over I start it up let idle turn on the lights and finish the walk around come back to the front look for leaks close the hood and then get ready to go. If the truck is in the shop it will be on shop air after starting will pull it out side to finish the walk around.

[vision386]

Personally,on a "cold start" (despite WHAT the temp. is) I start the engine,let it idle,do my walkaround,paperwork etc while warming up,i NEVER race the engine when cold EVER! but,i was taught old school,i've seen plenty of guys get in a truck and soon as it starts,floor the throttle building air pressure,if they worked for me,driving my equipment,it would be the first and last time they did it in my truck! Theres a video of a guy doing a cold-start on an R-Model on youtube,soon as it catches he floors it,i cringe everytime I see it!..........................Mark