Cold weather idling for heat

[themechanicalford]

In cold weather I was curious as to the safest way to extend idle the truck once it's hot? I've seen some things on here about switches you can use to control certain aspects of the timing and throttle speed.

If I am out and want to idle the truck for an hour or more for cab heat should I try to use the pedal to vary the RPM's, should I just let it be, should I add some sort of manual override?

Also would regular 15w40 be my best bet in these circumstances? I've heard people talk about switching to a thinner oil in cold temps. We live on top a mountain and deal with temps down to the single digits regularly.

Thanks!

 

[Reggie f250]

Once it is warmed up you can let it run to keep warm. I have no problem doing it when I have to work in the cold. Just remember if the engine is cold idling will not warm it up. In freezing temps you can run 5w40 oil. It will start easier and will not hurt anything.

 

[IDIBRONCO]

I've seen some things on here about switches you can use to control certain aspects of the timing and throttle speed.

What they do here is to use a switch to activate the fast idle solenoid which will also activate the timing advance. I can't back feed to anything since the factory "automatic" switch is in the open position at this point so electricity can't flow through it.

 

[franklin2]

What they do here is to use a switch to activate the fast idle solenoid which will also activate the timing advance. I can't back feed to anything since the factory "automatic" switch is in the open position at this point so electricity can't flow through it.

That should also activate the high idle solenoid if you activated the switch and then tapped the throttle afterward.

They claim some of these diesels idling for long periods cool off and thus start having incomplete combustion. So you start getting raw fuel in the cylinders. I think they call it "wet stacking"? I do know the 2009 powerstroke I use at work will start running faster and faster if I let it sit and idle for a extended period. After a certain period of time it will drop on it's own, or if I step on the brake getting ready to put it in drive it will drop back down. Then after awhile it will speed up again.

 

[miles1400]

@themechanicalford i use a fast idle stick, i stick it between the pedal and the seat, it works and a high idle is better for the engine. i let my truck warm up until the cold start advance/high idle turns off. then i just turn on the defrost on high and in 5-10 mins of driving i have good heat in my truck. no grille cover, no block heater, no fancy stuff. if you need to idle it for an hour for cab heat then you have some major problems with your truck

 

[Farmer Rock]

If the engine is running at higher rpm,it won't wet stack.I think that's what the OP is aiming for.Think of farm tractors running stationary pto implements such as a conveyor.The tractor is only being ran 3-400rpm above idle in most cases and last 10s of thousands of hours doing that alone.The damage is done when you idle for longer than you drive it and it doesn't burn hot enough to run efficiently.


Rock

 

[Farmer Rock]

If the engine is running at higher rpm,it won't wet stack.I think that's what the OP is aiming for.Think of farm tractors running stationary pto implements such as a conveyor.The tractor is only being ran 3-400rpm above idle in most cases and last 10s of thousands of hours doing that alone.The damage is done when you idle for longer than you drive it and it doesn't burn hot enough to run efficiently.


Rock

Also FWIW,I high idle every single one of my machines on warm up.It warms them up faster,and it's better for the engine.As for the original question,I would be curious to know as well


Rock

 

[IDIBRONCO]

That should also activate the high idle solenoid if you activated the switch and then tapped the throttle afterward.

@themechanicalford i use a fast idle stick, i stick it between the pedal and the seat, it works and a high idle is better for the engine. i let my truck warm up until the cold start advance/high idle turns off. then i just turn on the defrost on high and in 5-10 mins of driving i have good heat in my truck. no grille cover, no block heater, no fancy stuff. if you need to idle it for an hour for cab heat then you have some major problems with your truck

The OP was asking about long times idling after the engine's already hot. This is to keep heat inside the cab when it's cold outside.

 

[nelstomlinson]

They claim some of these diesels idling for long periods cool off ...

They definitely do cool off. I think the problem is that the egts get really low, and the engine just isn't making much heat, and isn't retaining much of that. If we had some way to mostly obstruct the exhaust when idling, to raise egts, that might help the engine stay warm and keep it and us comfortable. Maybe jam a potato into the tail pipe when you have to idle for a while?

Didn't the older powerstrokes have a valve in the exhaust which would close when you were idling in the cold?

 

[nelstomlinson]

If the engine is running at higher rpm,it won't wet stack.I think that's what the OP is aiming for. ... The damage is done when you idle for longer than you drive it and it doesn't burn hot enough to run efficiently.

Rock

Rock, I disagree with that first sentence. Our generators definitely wet stack with no load, and they definitely are always running at 1,800 rpm. Your last sentence gets it right: put a load on, get it hot, and you can burn the fouling out. We put the generators on a load bank to heat them up. We like to see 1,000F egts when we're trying to burn the fouling out of the generators.

 

[IDIBRONCO]

Didn't the older powerstrokes have a valve in the exhaust which would close when you were idling in the cold?

I think that they did have something like that. I remember that, completely stock, they wouldn't rev up very high when the engine was cold. At least that was the experience I had with the two or three that I did much with.

 

[nelstomlinson]

I have a '97 powersmoke sitting in the lineup. After breakup I'll take a look underneath and see if I see something that might be a valve.

I think that truck needs a head gasket. Maybe this year I'll get around to fixing it and selling it.

Edited to add: if there is a valve in the exhaust pipe, Rock Auto doesn't show it. Maybe I'm misremembering.

 

[gnathv]

The valve you’re looking for is in the output of the turbo housing.

 

[gnathv]

Above the down pipe.

 

[nelstomlinson]

Oh. Thanks, gnathv.

Edited to add: Found it! Rock Auto calls it a turbocharger exhaust adapter.