How long is engine warm-up?

Topic: How long is engine warm-up? (Read 1542 times) previous topic - next topic

Re: How long is engine warm-up?

Reply #25 – June 03, 2021, 03:58:06 pm

Quote from: bigdog – June 03, 2021, 02:11:36 pm

The B50 for the Electronic M11 engine is 800,000 miles until an in-frame refresh. Our coach engines are classified as being under rather lite duty service conditions. It is highly unlikely that any idling a coach does (which is minuscule idling compared to class 8 trucks) would ever lower that 800,000 mile figure anywhere close to the miles a coach will see in it's life time.

The idling warming up issue (at least to me) is more about good campground manners than worrying about whether that rebuild will happen at 600,000 as opposed to 800,000 miles.

Idling for more than a minute or so is not only against the law in many places but it exposes anyone in or around the motorhome to hazardous particulates. I can't believe how many people keep the engine idling at fuel stops.

Pierce

Re: How long is engine warm-up?

Reply #26 – June 03, 2021, 04:50:33 pm

For those of you that want to go down the rabbit hole regarding EPA restrictions on engine idling you can review the attached: https://www.epa.gov/sites/production/files/documents/CompilationofStateIdlingRegulations.pdf

Make sir you keep a copy of this handy if you ever travel to California, etc.😜

Re: How long is engine warm-up?

Reply #27 – June 03, 2021, 06:21:28 pm

Quote from: Pierce & Gaylie Stewart – June 03, 2021, 03:58:06 pm

Idling for more than a minute or so is not only against the law in many places but it exposes anyone in or around the motorhome to hazardous particulates. I can't believe how many people keep the engine idling at fuel stops.

Pierce

If we as RV owners were actually so concerned with particulates. We would sell them and drive Tesla's to a zero carbon footprint hotel and eat at organic restaurants instead of blowing through a gallon of diesel every 7-10 miles just to be somewhere where we 'want' to be for recreation/relaxation.

When my coach has sat long enough to go to zero PSI. It takes more than a minute to get aired up enough to even move an inch.

Re: How long is engine warm-up?

Reply #28 – June 03, 2021, 06:32:10 pm

I have to run the air bags up to clear the retractable jacks, when the air compressor pops off at about 120 lbs then it's time to leave.

Re: How long is engine warm-up?

Reply #29 – June 03, 2021, 06:46:31 pm

The EPA however is very concerned about it. Here is their publication: https://www.epa.gov/sites/production/files/documents/CompilationofStateIdlingRegulations.pdf. I remember what Los Angeles used to be before pollution controls. Without them, we would have coast to coast Love Canal.

Pierce

Re: How long is engine warm-up?

Reply #30 – June 03, 2021, 07:20:14 pm

Looks like this one has pretty well run its course.

Lots of views on both sides.

If something NEW, feel free to post.

Thanks.

Brett/moderator

Re: How long is engine warm-up?

Reply #31 – June 03, 2021, 10:04:10 pm

Quote from: Dan & Annie – June 02, 2021, 09:38:08 am

Yes it was cold overnight each time this happens, but how long must I warm up before attempting to get rolling? I don't like to upset the neighbors by idling for 15 minutes in my campsite before rolling out. 1998 U295, Cummins C8.3.

At the end of the day, your diesel needs to be warm to produce most of its power. How it gets there doesn't matter, Aqua Hot, block heater or driving around all accomplish the same goal: getting the engine up to operating temperature.

Build air, brake test, drive in first until you reach the road. No one enjoys leaving a big cloud of smoke behind, but some days it just can't be helped.

Re: How long is engine warm-up?

Reply #32 – June 03, 2021, 10:14:24 pm

It depends on the year and the engine as to what comes out the pipe. My '81 with the Cummins 555 smokes like a tar kettle until it get up to running temperature. On my '99 ISM the only thing out of the pipe in the morning is noise.

Re: How long is engine warm-up?

Reply #33 – June 03, 2021, 10:57:33 pm

That's what the electronic diesels have for a big emission advantage. Most will have a "smoke" setting where the computer won't add fuel until it sees boost pressure. That in turn, keeps the fuel/smoke down until the turbo can supply plenty of air for a more complete combustion. The smoke setting can usually be turned off so the computer fuels the engine immediately after you push the pedal down. With it on, the coach is a little slow coming off a stop sign. Especially true if it has a tall first gear like our U300's four speed has. And if you have a four speed with a fairly tall final drive, first gear has to be fairly tall or there will be an even larger RPM drop between gears. Example is the 4.xx to 1 first gear in our transmission compared to a 6.xx to 1 in the 6 speed transmissions. That's why I have to back up our driveway.

At lower elevations and warm weather like today, a start up is very clean with no smoke. Go up a couple of thousand and drop the temp and you get lots of smoke. Turbo engines like ours have lower compression ratios compared to a non-turbo. 17 to 1 vs to 19 to 1 in the non-turbos. This makes a huge difference in compression heating so starting is harder and white smoke is produced with the lower compression ratio.

Pierce

Re: How long is engine warm-up?

Reply #34 – June 04, 2021, 10:54:05 pm

I think I've posted this before but bares repeating...

At the GrandVention in Pueblo, CO a few years ago during the Auqahot talk someone asked when to use the engine heater. The answer was anytime you do a cold start. He then said that he asked Cummins what constituted a cold start. Cummins said anything under 90º was a cold start.

I use my heater for almost every morning start. If it is summer probably only a couple of hours or so. If winter all night. DWMYH...

see ya
ken

Re: How long is engine warm-up?

Reply #35 – June 05, 2021, 12:51:46 am

As do I. Why start off with a cold eng?

Re: How long is engine warm-up?

Reply #36 – June 05, 2021, 10:08:48 am

Quote from: kenhat – June 04, 2021, 10:54:05 pm

I think I've posted this before but bares repeating...

At the GrandVention in Pueblo, CO a few years ago during the Auqahot talk someone asked when to use the engine heater. The answer was anytime you do a cold start. He then said that he asked Cummins what constituted a cold start. Cummins said anything under 90º was a cold start.
I use my heater for almost every morning start. If it is summer probably only a couple of hours or so. If winter all night. DWMYH...
see ya
ken

Hey Ken,

You installed an external heater as I remember. What type, brand and photos if you have any?

Richard, It would be nice to have a warm engine when you start but not all engines have a heater that work quickly and does not need 110V. Our Detroit has a useless non-block heater. I have a small propane external block heater and plan to install it before next winter. They do get rid of all the campground smoke.

Pierce

Pierce

Re: How long is engine warm-up?

Reply #37 – June 06, 2021, 11:46:27 am

Quote from: Pierce & Gaylie Stewart – June 05, 2021, 10:08:48 am

Hey Ken,

You installed an external heater as I remember. What type, brand and photos if you have any?

John Fritz led the way on this mod. I simply followed in his footsteps.

Alternate Block Heater on 6V92 Detroits

Here is my post from 4 years ago.

More coach bucks - Page 2

The main issue with this mod is that the Hot Start needs to be installed beneath the mount for the dash air compressor. To do this you need to drain coolant. (20 gallons in my case!) Pull the dash air compressor and the mount. Then drill a 1 1/4" hole in the base of the mount so that the Hot Start can be mounted. Install Hot Start then install air compressor mount on top of it. Then reinstall compressor. I also ran a new circuit from my 120v circuit box just for the Hot Start.

I left my old engine heater in place so have the option run both heaters which I almost always do. Rarely boondock when cold out but when I do I usually run the generator first thing in the morning to give the batteries a boost and microwave some breakfast. I flip the heaters on while running the genny.

No photos. The area is so hidden no way to photograph.

Edit to add link to Hot Start.

Kim Hotstart DDV-151B

see ya
ken

Re: How long is engine warm-up?

Reply #38 – June 06, 2021, 12:21:32 pm

The Foretravel non-block heater is a poor alternate to the standard installation that all trucks, buses, Bluebirds/Wanderlodges, etc use down on the curb side of the block under the AC compressor mount. Foretravel installed it up top as almost zero coolant is lost changing it. With the stardard Detroit installation, all the coolant much be captured before the new block heater can be installed.

I did a block heater test on the Foretravel thermostat housing location in Bishop, CA (campground elevation about 4300 feet and had 110V power) is sub freezing weather with it plugged in all night. Using a IR gun, the block and cylinder heads were cold in the morning but the crossover pipe to the radiator was too hot to touch. The 1200 watt thermostat heater did not aid in starting that morning at all.

I'm installing a second alternator where the AC compressor was and will install a new block heater in that location at the same time. Also, my small propane block heater will be plumbed into the cylinder head and block at the same time. Small, low draw hot water pumps are inexpensive and can run for hours without depleting the batteries. Will post photos of that.

Since we only use the generator for AC, it's not a possibility in the morning so is the reason for using a propane block heater.

Pierce

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Re: How long is engine warm-up?

Reply #25 – June 03, 2021, 03:58:06 pm

Re: How long is engine warm-up?

Reply #26 – June 03, 2021, 04:50:33 pm

Re: How long is engine warm-up?

Reply #27 – June 03, 2021, 06:21:28 pm

Re: How long is engine warm-up?

Reply #28 – June 03, 2021, 06:32:10 pm

Re: How long is engine warm-up?

Reply #29 – June 03, 2021, 06:46:31 pm

Re: How long is engine warm-up?

Reply #30 – June 03, 2021, 07:20:14 pm

Re: How long is engine warm-up?

Reply #31 – June 03, 2021, 10:04:10 pm

Re: How long is engine warm-up?

Reply #32 – June 03, 2021, 10:14:24 pm

Re: How long is engine warm-up?

Reply #33 – June 03, 2021, 10:57:33 pm

Re: How long is engine warm-up?

Reply #34 – June 04, 2021, 10:54:05 pm

Re: How long is engine warm-up?

Reply #35 – June 05, 2021, 12:51:46 am

Re: How long is engine warm-up?

Reply #36 – June 05, 2021, 10:08:48 am

Re: How long is engine warm-up?

Reply #37 – June 06, 2021, 11:46:27 am

Re: How long is engine warm-up?

Reply #38 – June 06, 2021, 12:21:32 pm

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