Smoke at idle

[btoscano]

Hey all,



When I start my truck I get this hazing from the tailpipe... . very light shade of white or blue, not brown. I am not sure if this is normal, or indicates I need to adjust something!! In the winter months I thought maybe it was because it was cold... but it was 65F yesterday. This is the truck that had the reman pump and reman injectors in the fall (that pop at 3900-4000 psi from Cummins). Timing is about 1/8" up from the factory mark.



Thanks,

Brian

 

[JLEONARD]

I get this hazing from the tailpipe

Well it sounds like your exhaust system is intact.

Seriously it's not unusual for a diesel to smoke white ish when cold as the cylinders are not warm enough yet to combust all the fuel.

 

[btoscano]

Hmm... well last night I was heading home around 1 A. M. The truck had been on for 20 miles or so. I stopped at a gas station to buy a snack on the way home and left the truck idling for 5 minutes or so... when I came out I could see smoke all around the truck up towards the mercury vapor parking lot light. The coolant guage was slightly lower than the regular mark... and of course it was about 30F outside. So is this still normal... or does it suggest I need to make some adjustments?

 

[WyattEarp]

Brian

The smoke at startup is normal on these 12V engines, white smoke when its really cold is normal and when its in the teens or below it almost looks like a gasser. If your getting blueish smoke at startup and only last for a little while then i would say it might be either valve seals or you might need a valve adjustment. Now say you were having a constant blue smoke even after warm up i would say the valve seals need replaced but don't quote me on that as i have never had a diesel engine tore down but am familiar with gasser engines and a constant blue smoke while driving usually indicates bad valve seals. Someone that is more familiar jump in here and if im wrong let me know. After driving 20 miles as you indicated and then stopped for a period of time and left the truck running and came out with lots of smoke then you might need to check you valve adjustment and again guys that have more knowledge than me on these engines pleas jump in here... . Brian it doesn't sound like anything serious as i can shut down and the fire back up and i get a black/white puff from the tail pipe which i figure is contributed to the fact that when you shut down these 12V engines the injectors spray some fuel in to the combustion chamber and thats what causes it, unlike the 24V engine when its shut down the electrical sensors prevent this from happening.

 

[btoscano]

My first truck was a 1990 and it acted very differently which is why I'm asking... the 1990 would churn out WHITE smoke when it was cold... now that I've really been looking, this 1993 truck is churning out bluish smoke when I first start it. And its not uncommon for the truck to churn out bluish smoke when the coolant temperature drops off normal operating temperature. For example, this afternoon I idled the truck for a while because I kept moving it here and there while working on the ranch with the log chains, chain saws ... when the temperature first dropped the smoke was bluish, and after a few minutes it stopped... . it doesn't seem to be burning THAT much oil though... but maybe the rate of consumption is increasing between oil changes... time will tell.



How hard is it to replace the valve seals??? Hopefully easier than replacing the rear main!!

 

[WyattEarp]

Well unless they have come out with a new way to put valve seals in without removing the head thats the only way i know to replace them. I was hopeing someone with more knowledge than me on this has chimed in...

Have you noticed any increase in oil usage between changes? the difference between the 2 trucks could be the 1990 non intercooled and the 1993 is intercooled, not sure how much difference that would make. I know on my 1992 if i let it idle after running it the only time i get any haze smoke is when i take back off and get on the throttle of course how long are you idleing for also. I don't want to tell you wrong on this but maybe i have thrown out something that will help... I noticed on mine recently the oil level dropped, i had a back valve cover that was loose and seeping more than i thought, i tightened that up(still need to get a deep well socket for that) and i was also told to check my air charge tube that runs from the bottom of the Turbo, was informed that sometimes oil will begine to leak around the seal and get oil in the tube, mine had a very slight film of oil so i don't think its really leaking.

 

[btoscano]

The exhaust is real potent... I wonder if the blue is from diesel fuel somehow and not oil. I don't think I'm losing enough oil to warrant valve seals... the oil loss seems to be entirely related to the rear main and tappet cover gaksets. I think I'll pull the injectors and have them tested and reshimmed to 3625 psi (stock)... these are Cummin reman that pop tested at 3900-4000 psi. I suppose one other alternative is to bump up the timing and see if that helps offset the increased pop pressure.



Brian

 

[WyattEarp]

if your exhaust is that strong then its running rich, one way to test is if it burns your eyes(not recommended) lol, that could be the cause if you have reman. injectors instead of the originals that have wear on them. As for the timing i have never messed with the timing as i like my trucks stock... One of the other guys in the group could tell you about retarding or advancing the timing on a diesel. Hope you find out what it is, that could be it now that i think about it, alot of guys have done the timing after a new injector or bigger injector install, at least thats what i have read over the yrs. on here, maybe someone else can help out with that... or do a search for advance timing or something to that nature.

 

[Greenleaf]

It's very easy to replace all the valve seals when your upgrading to the 60# valve springs. They are simply setting there staring up at you asking to be replaced.



I purchased mine from Cummins and they are not expensive. There is NO kit so pleez don't ask. Just buy 12 valve steam seals. Maybe get six new cover gaskets and the little O rings.



Pastor Bob just recently announced that there is a new valve steam seal for really high rpm's. I don't know what they are but he did mention this. The ones I installed do have the spring at the base so I seriously doubt they will creep.

 

[btoscano]

GL,



Why would I need 60# springs??? And do I have to remove the head like WyattEarp suggested?



I don't think I need either, but now you've got me interested.



I already replaced the VC gaskets and o-rings... in fact I did that at the first oil change where I bought the truck when I was 2000 miles from home... . well 4000 miles since I took the scenic route home.

 

[Greenleaf]

The heavy springs will only serve to prevent valve float when you operate at or above 3,600 rpm. Most do NOT install them. Only if the above would apply.



There are several pictures in my readers rig gallery to R&R the springs. The same procedure would hold true to R&R the stem seals only becasue the spring must be removed. It's quite an easy operation. It's just time consuming and intimidating the first time through.

 

[btoscano]

The pictures show the head still installed...



I like the red VC's.



-brian

 

[TKingsbury]

If it is quite cold, and you are idleing your engine, I would think it is just water wapor. I do not live in real cold weather, but when I go places I notice different things. It seems to me, depending on humidity and such, pretty much any vehicle will be emitting some type of smoke/steam. I just ignore it myself, chalk it up to cold weather. This may not be your problem, but I thought I'd chime in. Also, it will not be possible to pull oil through the valve seals or piston rings while under boost. If it smokes blue at idle, and goes away with some boost maybe you are sucking a bit of oil at idle.

Travis. .

 

[btoscano]

Could be... . I'm going to wait and see what happens as we get into warmer spring weather more regularly. I'm also going to switch to Delvac 1300 Super 15w-40 next month and use auto-rx to see if it will slow/stop the rear main seal leak... that might help out any valve seal issues too. Right now I have Delvac 1 5w-40 to help with the cooler winter temperatures.



-brian

 

[91W350]

My 91 has done that since the day I bought it. It still does not use enough oil to add between 5,000 mile changes. Gets right around 20 mpg most of the time, sometimes a little higher, sometimes a little lower, which I think is great for a one ton 4wd box pushing it's way down the roadways. Unless you start getting a lot of oil consumption or fuel mileage dives, I would not give it much worry. Mine is much worse in the cold too. My 93 does about the same on fuel and oil, has a lot less power and very seldom smokes at all. I like the power and smoke better! :-laf :-laf Give me a little smoke, a little rattle and heaven is just a little closer. Glen

 

[btoscano]

I pulled the injectors and had them tested at the shop that adjusted my pump, they are firing between 222-230 bar. This is interesting because the shop near Daniel Puckett tested them right out of box and said 3900-4000 psi... So either the injectors lost 600-700 psi in 7000 miles, or somebody's guages are off, or a bit of both...



Anyway, I suppose that leaves TIMING as a possible problem... so I'm going to get into checking that a bit more closely and adjusting.

 

[btoscano]

Hey guys,



Does this look like the tool that would set timing "by the book" ???



Thanks,

Brian

 

[BushWakr - RIP]

Yup that is part of the tool(s) needed to set the pump timing using the plunger lift (mm) method. You'll need a magnetic mount to hold it to the block as well as some other goodies... . maybe Scott (Greenleaf) can jump in here with the rest...



If your exhaust has a very acrid or strong almost burning smell it is likely you timing. . and... .

Injectors for our trucks (especially the VE pump) work well when set to about 260 bar... you can ususally go between 250 and 265 bar. I prefer a bit more like the 260 setting because it's a little more gentle on these poor old VE pumps...



pb...

 

[Greenleaf]

You need the sleeve that threads into the pump's high pressure head. Then you'll slide the gizmo you have pictured INTO the adapter sleeve. It will have a thunb screw that locks the dial in place when you have it set accoring to the directions.



Then you simply rotate the pump and the dial will NOT move on it's mount thus imparting the motion of the pumps plunger onto/against the dial plunger making a reading.



I should have been a freakn' school teacher... . oh wait... . I WAS.

 

[Dieselman359]

teacher GL

I should have been a freakn' school teacher... . oh wait... . I WAS.

Oh my :-laf