Well my glow plug controller has shot the wad, AGAIN on my 04. The problem has been periodic lately, and I didn't make second thought of it until I got to breakfast this morning and found that they didn't work at 24 degrees outside. After a half hour of not running, it was very difficult to get it started again. I didn't have time to go home and drive my other truck instead, so I continued to school. They are not fuctioning at all and I have nowhere to plug the truck in, so I have left it idling in the parking lot since 8 this morning. So far the temps have stayed right around 300 degrees (EGT) but I am curious about this wet-stacking issue. At what temperature does this begin? After idling through first period, it has begun to wisp a tad of smoke periodically, but the temps are still almost 300 degrees. After a full 8 hour idle without moving, will the effects have the potential enough to where changing the oil will be neccessary? Just curious as to what REAL damage it can do.

 

Dude 8 hours!
Beats me, your the guru!

 

Hey PSD...good to here from you again.

Just curious as to what REAL damage it can do.

I don't mean to be flippant here but, isn't this kinda like...well...I just shot myself in the foot and I wonder how much I'll bleed?

As you know all the mfgs warn about wet stacking due to extended idling but I don't think any are specific out extent of damage or other issues.

I think the Alaska boys do this all the time though so I am sure you will hear form them soon.

Another test performed LIVE by PSD.
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LOL...yes, it is

I think if I change the oil again I will probably be alright, I am just curious...

 

kw provided me this link:

http://intellidog.com/dieselmann/b_smoke9.htm

According to it I'd be more concerned with the exhaust valves.

 

Well, that actually makes me feel a little better (in concern to the fuel quality mentioned in that article) thanks to the fact that I have about 3 times the recommended amount of fuel additive in it presently. I have actually never heard of the sticking valve issue, thanks for the article. I'll be sure to *remove* any possible deposits when I leave today

 

I'll be sure to *remove* any possible deposits when I leave today

Somehow that does not surprise me.

 

Extensive idling can cause excessive ring wear and plugged injector tips. This is caused by the drop in clyinder temp. and unburned fuel "washing" the oil off the clyinder walls. Can also cause excessive "blow by" and possible fuel in oil.

Info. from-Cummins 505 service manual.

 

I think the most that I let my truck idel is 7 hours. I havent had any issues - yet. The wetstacking issue is in the back of my mind. I didnt get the Idle Control and there are time that I wished I had. Looking at getting an auto start that has a temp sensor that will turn on the motor every time need, either by setting a time to turn on or by temperature readings. I now live in the tropical regions of Alaska were winter temps are average 20. Every so often we go North to visit friends. Ranges from -20 to -60 and I just leave the truck idleing the whole time. Might see 2-4 hours of idle time. ITs a major pain to try to get a vehicle started at those temperatures when the motor is cold.

I did work on the Slope years ago. We had F350 with Matt-tracks. We would run those things at idle during the night time then they would get driven to a new job site during the day and sit and idle once on site. They would start those diesels come Dec and usually not shut them down until March. If it warmed up, above 0-10, then they might get turned off.

We do idle our vehicles at work, 7.3, for 2-4 hours at times and we havent had any problems in the past 10 years. The guy you want to hear from are those from Fairbanks and those that work on the Slope. That is a common practice for them. I have been out of the loop for awhile when it comes to constant really cold temps. Since this thread was brought up could someone educate me on what might be the signs or symptoms of early onset of Wetstacking? Just curious

 

Wet-Stacking is a common problem with diesel engines, which are operated for extended periods with light or no loads applied. When a diesel engine operates without sufficient load it will not operate at its optimum temperature. This will allow unburned fuel to accumulate in the exhaust system, which can foul the fuel injectors, engine valves and exhaust system, including turbochargers, and reduce the operating performance.

In order for a diesel engine to operate at peak efficiency it must be able to provide fuel and air in the proper ratio and at a high enough engine temperature for the engine to completely burn all of the fuel. Wet-Stacking does not usually cause any permanent damage and can be alleviated if additional load is applied to relieve the condition. It can reduce the system performance and increase maintenance.

Applying an increasing load over a period of time until the excess fuel is burned off can repair the condition. This can take several hours to burn off the accumulated unburned fuel.

 

mlb4966

Mike
If you look at semi trucks or heavy equipment, farm tractors ect, you will see the "black sludge" running down the outside of the exhaust stack. Once a heavy load is applied the fuel will burn off.

 

What would be the ideal temps to ensure wetstacking does not occur. Or for those of use that dont have a EGT gauge what would be the ideal minimum RPM's to ensure proper temp? Also will the excessive fuel evaporate over a period of time.

 

So would I see, lets say, more than normal white smoke due to excessive fuel once I got in the truck after a period of idle and starting to drive it?

This is why I love this site. Great information to be had.

 

Normal driving in your truck will reach 900 to 1200 Degrees which will burn off the fuel. I do not see a problem with extended idle as long as you make sure to bring the truck back up to operating temps.

I would increase my oil changes if the engine does see extended idle times.

 

I like the idle strategy of the PSD. The PTO switch to up RPM's is nice to keep the oil flowing to bearings. For wet stacking just make sure to clear out the exhaust.........In Matts (PSD) case I am sure the pipes are clean now.