Community Forums

Waywards · 12-23-2017, 04:24 PM

I've been told by several people that it's not good to idle my 2017 diesel pusher for extended periods. Is this true and if so what's the reason?

wildcatter · 12-23-2017, 04:32 PM

Quote:

Originally Posted by Waywards

I've been told by several people that it's not good to idle my 2017 diesel pusher for extended periods. Is this true and if so what's the reason?

If a diesel idles to long the fuel does not burn like it is supposed to, the unused fuel can and will leak past your pistons and dilute your oil, and possibly glaze your cylinders, the fuel that does burn does not burn efficiently and will soot you emissions and cause issues. But you also don't just want to shut it down either, if you have been doing heavy driving, you want to idle the engine for 5 minutes to cool down the Turbo. If you do need ot let it idle longer you can set the high idle, on the cummins it jumps the RPM up to 1100 to 1500.

You will also want to keep your air filter clean, they say every so many miles (I believe 20-25K or every 2 years), I change mine every year with the oil and fuel filters. I know I don't need to but I feel better. If you let your air filter get to dirty you can dust your cylinders.

**Lt Dan** · 12-23-2017, 04:43 PM

Quote:

Originally Posted by Waywards

I've been told by several people that it's not good to idle my 2017 diesel pusher for extended periods. Is this true and if so what's the reason?

Directly from the ISL9 operator's manual:

Do not idle for extended periods of time. Excessive idle time can cause poor engine performance.
Internal combustion engines must not operate at low idle speed for extended periods of time. This operating condition
may lead to poor engine performance. The idle shutdown feature, available on most Cummins® engines, can be
programmed to shut the engine down after a period of low idle speed operation with no driver activity. A flashing
warning lamp will inform the driver of an impending shutdown. If an engine must idle for an extended period of time, it
should be done at fast idle (1000 rpm or greater). The Power Take-Off (PTO) feature, available on most Cummins®
engines, can be programmed to adjust engine speed with the use of OEM switches to pre-programmed set points.

Tony Lee · 12-23-2017, 04:44 PM

When in doubt, read the instruction

With modern diesels and normal driving habits there is rarely any good reason to idle before shutdown. Normal slowdown off a highway exit is quite long enough.
Same with a cold start. Start the engine and move off slowly with minimum throttle and drive gently until the temperature gauge moves off the stop.

Doing that will not harm the engine and will greatly improve your standing in the eyes of all your neighbors who would otherwise have to endure the 30 minutes of idling evening and morning that stupid people seem to think is necessary.

MSHappyCampers · 12-23-2017, 05:01 PM

It seems I remember reading somewhere that it shouldn't be idled more than 15 minutes.

Outbound · 12-23-2017, 05:08 PM

On the other hand you do not want to start and stop engine within 10 minutes, when we stop at RV park to check in I leave motor at idle, not sure if it's good policy but for check in it seems OK.

funjnt · 12-23-2017, 05:12 PM

There are many different opinions on here in regard to idling. I have some previous posts which document turbo failure and head gasket failure as of shutting down at too high a temp.

I have a lifetime exposure of diesel engines, farming, trucks, tractors, on and off highway equipment.

I will simply put it this way. In the cold I will never move a machine or truck with out warming up. I think five minutes minimum is the least I would perform. I sometimes idle my machines or trucks (rv included) up to half an hour and sometimes more to really warm up all the components. To each his own.

I also idle down anything before shut down not just a cruise down the off ramp, not sufficient for me. I prefer all the temp in the engine, trans and hydraulic system to stabilize before I am comfortable shutting down.

I have three ford powerstrokes with over 250,000, dozer with over 7,000 hours, dump truck with over 420,000 miles and various smaller machines both gas and diesel. All with no problems related to anything I have heard of by idling something for 20 mins give or take.

I can try to reference my long post on a machine of a friend of mine, two actually, who never warmed up or shut down adequately. Turbo bearing gone, head gasket gone and another machine turbo gone.

I do agree there is a line to idling too long but I will never get in a cold engine and just go no matter how gentle you ease into it. I will make a 97 Cat 3406e reference. In the owners manual Cat said to high idle the engine until the temperature gauge was coming off the bottom before operation or driving, this is in cold weather. Even then the computer would de-rate the engine or not allow full power until it was at a certain temperature.

This is just how I have operated and was taught to operate machines and trucks. I know we all will have similar situations and different methods. To each his own and I must say take the middle road maybe LOL. Don't idle too long and don't idle too little, moderation? Yeah.

Bigd9 · 12-23-2017, 05:35 PM

Check out this recent link for almost 80 post on the subject.

http://www.irv2.com/forums/f124/do-y...le-362844.html

Shawn6596 · 12-23-2017, 06:25 PM

I was wondering if you all were only referring to newer engines? Semi's used to run literally 24 hours a day. I have a mechanical 8.3 cummins. Does that make a difference?

Fiesta48 · 12-23-2017, 06:45 PM

Funjnt, newer diesels since 2010 with DPF, DEF, and Cat Converters should not be idled for more than 10 min. due to plugging up the DPF. Diesel Particulate Filter. Hundreds of $ to repair, if the regeneration cycle (flushing/burning out) can't.
My engine readout has a idle time percentage so idle time can be monitored by me and by the engine mfgr.

Pusherman · 12-23-2017, 06:48 PM

Quote:

Originally Posted by Outbound

On the other hand you do not want to start and stop engine within 10 minutes, when we stop at RV park to check in I leave motor at idle, not sure if it's good policy but for check in it seems OK.

Nope. Have you noticed that delivery trucks (including semi trucks) have an automatic shutoff which shuts of the engine if left idling? The driver then jumps in and starts it up again. Doesn't hurt it at all. How about all the start-stop technology in cars today?

Idling wastes fuel and is potentially harmful to the engine as other posters have mentioned above, with raw fuel not being completely burned at idle, washing down the cylinder walls, removing any lube and potentially causing scoring to the cylinder walls, and dilutes the oil. Running at high idle precludes this from happening.

Regarding cool-down, a turbo wants to be cooled down so to not coke the oil. If you have come off an exit ramp, and drive another mile or so at slower speeds, as when entering the campground, you have cooled the turbo down sufficiently. I add another minute at idle (assuming I haven't just come off a high speed exit) and shut it down. Saves fuel and our environment (and my engine).

Plus I think it's rude to the neighbors in the campground to let your diesel engine idle excessively.

stuhly · 12-23-2017, 06:57 PM

Bumping it up above a dead idle disables automatic shutdown. Mine is not moving until temp gage moves off the bottom. Just doesn't matter if neighbors like it or not.

Fiesta48 · 12-23-2017, 07:00 PM

Manual says just pulling of the highway as in rest areas is sufficient turbo cooling. '14 ISL 380.

NHRA225 · 12-23-2017, 07:01 PM

Quote:

Originally Posted by Pusherman

Nope. Have you noticed that delivery trucks (including semi trucks) have an automatic shutoff which shuts of the engine if left idling? The driver then jumps in and starts it up again. Doesn't hurt it at all. How about all the start-stop technology in cars today?

Idling wastes fuel and is potentially harmful to the engine as other posters have mentioned above, with raw fuel not being completely burned at idle, washing down the cylinder walls, removing any lube and potentially causing scoring to the cylinder walls, and dilutes the oil. Running at high idle precludes this from happening.

Regarding cool-down, a turbo wants to be cooled down so to not coke the oil. If you have come off an exit ramp, and drive another mile or so at slower speeds, as when entering the campground, you have cooled the turbo down sufficiently. I add another minute at idle (assuming I haven't just come off a high speed exit) and shut it down. Saves fuel and our environment (and my engine).

Plus I think it's rude to the neighbors in the campground to let your diesel engine idle excessively.

I agree with all the above - But I pull into a Rest area's and the trucks idle all night long - Me ? I shut is down after 5 min or so !
Why do they do that ?