Reducing oil smoke

[Viridiansky]

Hey all,

been lurking for a bit and just became a member. I got a '82 720 KC that just passed the 240K mark. Got it about a year ago and have slowly been fixing things up on it.

So the question I need help with is with that thick oily smoke on startup and harder accelerations. I have no external oil leaks except a tiny bit from the pan seal, but it still eats about a quart a month. I've been told that it's probably a piston seal or four, or maybe the valve guides, that are leaking. I don't know too much about the internal engine parts, been too cautious to open that up.


So, is it true, about the seals and/or guides? Or are there other possible causes? If it's the seals, does that mean a engine rebuild?

Thanks for all the other good info,
Joshua

[zen]

As a GENERAL rule....for knackered engines (smoke may be caused by other reasons) BLUE engine oil smoke on power (acceleration, uphills etc)= worn piston rings/bores.

BLUE engine oil smoke on deceleration (lifting of foot,engine breaking going down hill etc)= worn valve guides/seals.

On start up it could be valve guides/seals allowing oil past whilst standing.

There is no reason why both can't be knackered.

Are you using the correct oil??? If engine has breathing system other than open road draft tube is that blocked??

[philip]

Hey all, I've been lurking for a bit and just became a member. I got a '82 720 KC that just passed the 240K mark.
-snip-
So the question I need help with is with that thick oily smoke on startup and harder accelerations. I have no external oil leaks except a tiny bit from the pan seal, but it still eats about a quart a month.
-snip-
So, is it true, about the seals and/or guides? Or are there other possible causes?

First ... please tell who/what you are. Thanks

In the SD22 engines you'll notice an oil blowby pipe (Road Draft tube) exiting on the low left side of the engine block which ... will NORMALLY lose oil that works back round the rear of the engine pan. So even if rings, stem seals, etc were -perfect-(...this can NEVER be...) the engine crankcase would still lose a lot total oil. Notice your clean driveway! Notice the SD25 is different (in several way).

"...thick oily smoke on startup and harder accelerations." What you see on a start-up puff is normal for old type diesels. Then, "smoke" seeing during accelation is not likely to do with oil. Rather ... the black smoke (exhaustion) results from too much fuel (carbon "soot"). Whole different discussion.

[Viridiansky]

Thanks for the info on the blowby pipe. I'll take a look at it. and the hint about seals vs. guides.

Rather ... the black smoke (exhaustion) results from too much fuel (carbon "soot"). Whole different discussion.

Has this discussion happened yet. Where can I find it?

thanks again.

[philip]

Rather ... the black smoke (exhaustion) results from too much fuel (carbon "soot"). Whole different discussion.

Has this discussion happened yet. Where can I find it?
thanks again.

There are several soot, oil, exhaustion, emission discussions ... already in these forums. Have you "happened" yet?

[asavage]

Have you "happened" yet?

Reminds me of author Dean Koontz's "becoming" phrase that he uses in a couple of his novels.

What did you mean by "happened"?

[philip]

Have you "happened" yet?

Reminds me of author Dean Koontz's "becoming" phrase that he uses in a couple of his novels.

What did you mean by "happened"?

RE: "Has this discussion happened yet. Where can I find it?"

I asked "Viridiansky" to find forums cluing smoke titles. Three pages of forums exist.