Smoke Under Load

[rickrat]

Im still new to diesels. I have an 83 6.9. I have always heard that under heavy load, or going up steep hills under full throttle that they will blow some black smoke. Mine does not blow any smoke at all, no matter what I try. It does shoot a little grey somke when starting up in extremely cold weather, but then stops, otherwise nothing at all.
Does this mean that I am not utilizing its full power potential? Is it out of tune?

 

[FordGuy100]

You could have a high altitude IDI. Other then that, it could be your IP and injectors are getting old and worn out.

Whats the altitude you live and drive at?

 

[Dirtleg]

It means you could use more fuel but you don't have to. If it's starting good warm and it runs well I would leave it alone. I would not turn up the fuel until after you have installed an EGT gauge. (pyrometer) example;

My truck had a dying IP. It would start cold but not hot. I installed a remanufactured IP from International. It is supposed to be calibrated to factory specs for my model year and transmission. At the same time I installed it I put in an EGT because I feel that this information is vital to know on a diesel. Well let me tell you that this stock calibrated pump under full throttle with no load on truck could easily cause a meltdown inside the motor due to high EGT's. It will put out a little smoke but not an inky black stream of it like you see some diesels doing. If I'm on the highway I can't hardly see the smoke under heavy load (8000 lb trailer 1050 EGT's)

So unless you just don't have enough power to get around like it is I wouldn't do a thing. If it starts well and runs good and doesn't smoke then you are probably just using less fuel than you would with the fuel turned up. If it smokes all the time at idle (really greyish) then I'd say you have some fuel issues but you said it only does it cold. Sounds more like glowplugs than anything else.

Hope this helps.

 

[Agnem]

Timing is retarded, and pump is worn. Nothing to be worried about, as this is a naturally occuring phenomena. Get to one of our IDI meets, and get your timing set, and your pump turned up (provided of course that you properly install the aforementioned EGT guage).

 

[fuzzy1626]

You may not be using it's power potential, but you are burning all the fuel that goes in the motor. Remember, black smoke is unburned fuel. At $3.59/gal thats the way I like mine to be. If I was pulling heavier than my boat, I might want to turn it up some. Right now I can pull the boat up the mountain at 55 and not even come out of overdrive (unless someone gets in front of me).

 

[Andylad13]

3.59 eh?? how about 3.93.

 

[Diesel JD]

Its so much the better if you don't leave a real smoke trail, just waste and pollution. Personally I think its okay for a diesel to blow a little black/brown when its being lugged or under heavy throttle, but a cloud of smoke all the time is not good.

 

[rickrat]

I live in the Virginia/Kentucky Mountains. It does struggle to pull some of these hills (they are very steep hills) when empty, but that may also be due to the rear gears. At 55mph Im doing about 1950 rpm's, maybe 2100 at 65 or so at the most. It is an F-350 dually. So it is a heavy truck anyway, engine is supposed to have 114,000 miles. It starts really easy when warmed up, not even a second of cranking to start. When cold it is a little harder, but only smokes for a few seconds. It has the 4 speed transmission. When climbing the big hills empty, I have to downshift to 3rd gear and that limits me to about 45 mph. Havent loaded it down yet to see how it does under full load.

Something I checked as well was the blow by. It has absolutely none at all. When idling or when revved up, nothing comes out of the oil filler.

Also, we have had some really cold weather here, but it seems like it doesnt run very hot. I can hold on to the upper radiator hose and it is warm, but not really hot. The temp guage shows it near the middle, and the heater blows hot air. Maybe it is not running warm enough?

 

[Agnem]

Most of what you describe sounds normal. Do yourself a favor and make it a priority to install real water temp, oil presure, and EGT gauges soon. The stock gauges are crap and cause more worry and questions than they answer.

 

[rickrat]

How hard is it to install the EGT Guage? Does it go into the exhaust?

 

[FordGuy100]

How hard is it to install the EGT Guage? Does it go into the exhaust?

Its not to bad, I had Russ do it as I watched when we did my turbo install. Basically, you have to take a drill to the intake manifold and drill a pilot hole, then step it up to the right sized drill bit (Depends on the thermocoupler you get, what size it is), and then tap it and it is done.

 

[Agnem]

You CAN drill the exhaust manifold, but I leave that to the purists. If you put it within 3" of the outlet in the exhaust pipe your good to go. Just drill a hole in the pipe, and use one of the clamp on probes.

 

[hesutton]

Basically, you have to take a drill to the intake manifold ...

Justin means the exhaust manifold.....just a little typo, but you don't want to put it in the intake.

Heath

 

[FordGuy100]

Justin means the exhaust manifold.....just a little typo, but you don't want to put it in the intake.

Heath

Whoops my bad, yes EXHAUST manifold