If idle is to be avoided?

Originally Posted by North_Maine
I discovered my 2017 Cummins 6.7 had over 2000 idle hrs on it in spite of the low 24000 miles when I bought it last August. I have yet to uncover an issue I can attribute to the idle hours. These new diesels are also able to regen during idle. It gobbles up fuel be side you get no passive regen to keep the DPF clean but it works.

A webasto or espar hydronic heater is well over $1000 installed so you need to be doing some serious idle time exclusively for heat purposes to make that worth it.


If a truck burns 5 gallons of diesel in a 10-hour overnight idle, that is $15 of fuel if it's $3/gallon.
A Webasto uses something like .06 gallons per hour, so it would use 0.6 gallons in a 10-hour overnight.
That is a savings of 4.4 gallons, or $13.20 in fuel cost per night. It would take 76 nights of use for a Webasto to pay back $1000 in fuel if the above assumptions hold. That is about 11 weeks on the road, so it would pay for itself in a winter.
That's the economics of my old truck.

My 2008 truck burns about 9 gallons if it goes on its 1000 rpm fast idle, and does a couple of regens overnight. The Webasto would save 8.4 gallons each night, or $25.20, making the payback 40 nights to save $1000.
I'm thinking about it.
 
Recently I've seen gasoline powered cars have the "no dole" feature where the car turns off at the traffic light or in the middle of a jam on 405/George Washington Bridge/ Jersey Turnpike. Are there diesels with this feature? If so, wouldn't there be an unusual strain on the starter motor AND the constant glow plug actuation?
 
Originally Posted by pitzel
High no-load idle might even be worse than no-load idle as a diesel takes in and has to 'heat' twice the air, and less engine output proportionally is used to drive things like the alternator and other accessories.

I "idle" my WVO engine at 2000rpm for about 2 minutes when I start up in the morning and have to climb my steep hill to get out of home. Else, I can wait forever until the engine gets up to temperature where it has enough power.
 
Mr. Doug Hillary used to recommend minimal idle time. If I remember correctly, under almost all circumstances, 30 seconds warm up, or until idle smoothed out, and drive off. Knowledge fell on deaf ears and I understand why he is not active anymore.
 
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Originally Posted by A_Harman
Originally Posted by North_Maine
I discovered my 2017 Cummins 6.7 had over 2000 idle hrs on it in spite of the low 24000 miles when I bought it last August. I have yet to uncover an issue I can attribute to the idle hours. These new diesels are also able to regen during idle. It gobbles up fuel be side you get no passive regen to keep the DPF clean but it works.

A webasto or espar hydronic heater is well over $1000 installed so you need to be doing some serious idle time exclusively for heat purposes to make that worth it.


If a truck burns 5 gallons of diesel in a 10-hour overnight idle, that is $15 of fuel if it's $3/gallon.
A Webasto uses something like .06 gallons per hour, so it would use 0.6 gallons in a 10-hour overnight.
That is a savings of 4.4 gallons, or $13.20 in fuel cost per night. It would take 76 nights of use for a Webasto to pay back $1000 in fuel if the above assumptions hold. That is about 11 weeks on the road, so it would pay for itself in a winter.
That's the economics of my old truck.

My 2008 truck burns about 9 gallons if it goes on its 1000 rpm fast idle, and does a couple of regens overnight. The Webasto would save 8.4 gallons each night, or $25.20, making the payback 40 nights to save $1000.
I'm thinking about it.



In your case- absolutely it makes sense. I stand by my statement: I consider you to put on some serious idle time- far more than tomato others.

Another boost for you- I may not have looked at the idle hours before buying but many buyers will, and I will in the future. By using an espar you'll be able to keep your logged idle hours down (assuming it's on a truck that logs idle hours)
 
Originally Posted by whizbyu
Recently I've seen gasoline powered cars have the "no idle" feature where the car turns off at the traffic light or in the middle of a jam on 405/George Washington Bridge/ Jersey Turnpike. Are there diesels with this feature? If so, wouldn't there be an unusual strain on the starter motor AND the constant glow plug actuation?



Sorry couldn't edit. the typo.
 
My wife drives an F150 with the 3.0 PowerStroke diesel which does have the auto start/stop. The glow plugs only cycle during cold-starts, so that isn't an issue.
The battery is an AGM, so battery is sized for application, the starter and other engine components are up for debate as far as premature wear.

The auto start/stop doesn't bother me or her, its just part of progress, and the truck with the 10 speed is phenomenal.
 
My Volvo S60 idle at 2k rpm at startup for like 10-20 sec before it drops off to normal, after that i just drive off. When i lived in northern part of the country where the winter is really cold i would let my car idle for 15-20 min to get the fluids warmed up a bit and in the meantime i would brush off snow and scrape the windows before just drive off. Vehicles do get heated up faster when driving so idling for a long time to get it up to high temperature is kinda poinless unless you really want heated cabin before driving off.
Volvo busses i work on have a heating feature when its cold, the engine idles at 1k rpm with exhaust brake engaged to bring the engine up to temperature, but it cuts off at 75C after like 15-20 min. So after that no point to idle further, just drive off like normal.
By my opinion idling for a long time is poinless, if its really cold its beneficial to idle for longer time to get fluids up to temperature to avoid wear.
 
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Originally Posted by whizbyu
Recently I've seen gasoline powered cars have the "no dole" feature where the car turns off at the traffic light or in the middle of a jam on 405/George Washington Bridge/ Jersey Turnpike. Are there diesels with this feature? If so, wouldn't there be an unusual strain on the starter motor AND the constant glow plug actuation?


Yes there are about as many diesels with a stop/start system as there are gas engines. Most engines with that feature use strengthened big end bearings, uprated starter motors (hyundai claims 250k starts vs 50k starts) and monitor battery charge and health states so the engine can be restarted. If there is an unusual demand from the heater/AC the feature is switched off. Uprated batteries are common aswell, either bigger sized EFB or regular sized AGM.

Glow plugs don't activate if the engine is hot enough. A few degrees above freezing is hot enough for some, others want 60 degrees F.

Wether theres an actual savings there, besides during econmy testing is another debate. after 3 minutes the engine typically restarts regardless and 3 minutes of idling in my diesel consumes about 0.03 liters of fuel, that's under 0.01 gallons.
 
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