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-   -   Exaust smoke (http://www.peachparts.com/shopforum/diesel-discussion/75996-exaust-smoke.html)

Adam 77 300D 09-28-2003 10:10 PM

Exaust smoke
 
I am getting a fair amount of smoke from the exhaust, the volume of smoke is relative to engine speed. I just recently rebuilt my vacuum pump, and figured that would fix the problem, it only helped slightly.
I am thinking that it is the cam case vent line that is feeding oil to the intake. Any ideas what I can do with that? Why does the cam case need to be vented into the intake? Can’t you just put a filter on the cam case hole, and plug the intake end of the line?
Maybe I am missing something here, so any advice is welcome. Thanks.

Cazzzidy 09-28-2003 10:49 PM

What kind of smoke is it?

If its black as all hell, its oil from somewhere. The vacume pump repair would only help if you had a problem in your vacume system - as the diaghram tearing causes the oil to slip through, and also causes a complete loss of vacume assist to brakes and what not.

I hope it isn't unburned diesel fuel smoke -- I wish a punishment like this on no other man. Unburned diesel is stinky and whitish, and occurs when a cylinder is not firing or combusting properly. This can happen to a cylinder with bad compression, or could point to an injection issue. In my unlucky case, I needed to replace the entire $500+ injection pump to cure the problem.

Keep us updated.

kerry 09-28-2003 11:11 PM

I've seen oil smoke burn blue (in relatively small amounts) and white (in copious quantities) but I have never seen it burn black.

Are you using oil? How much blowby do you have when you remove the oil filler cap?

The crankcase needs to be vented somehow. Into the intake is as good as anything else.

Adam 77 300D 09-28-2003 11:41 PM

The smoke is white. I was under the impression that white smoke was from oil, and unburned fuel would be dark or black. I am a bit concerned now.
I will check to see how much blow by I get from the oil filler. How would I go about doing a compression test? Same as a gas car, only through the glow plug or injector ports?

Adam 77 300D 09-29-2003 12:10 AM

The smoke is white. I was under the impression that white smoke was from oil, and unburned fuel would be dark or black. I am a bit concerned now.
I will check to see how much blow by I get from the oil filler. How would I go about doing a compression test? Same as a gas car, only through the glow plug or injector ports?

ForcedInduction 09-29-2003 01:39 AM

White smoke can also be coolant... i.e. blown head gasket. Take a look down the cooling tank and check if it looses any coolant at all.

The diesel from my smokescreen is greyish white with a VERY strong dieselish smell. Smoke could also come from incorrect timing, by chain stretch or improper adjustment.

300sd2000 12-01-2003 09:48 PM

Hello,

I'm having a similar problem differentiating what's causing my copious amounts of white smoke...

Everything's been going well, can't understand why all this whitish smoke on takeoff from the stop light most notably.

It has a very strong diesel odor so I think I'm just not burning it completely...

the injectors were done 10 years ago! at 140K and the car now has 270K. I'm betting its the injectors? Although I heard someone once say that injectors rarely go bad....

Could poor valve adjustment cause this? That was done 2 years (30K) ago?

240Demon 12-02-2003 04:26 PM

Check your injection pump timing, as I had a problem with copious amounts of black smoke coming from my 240D. We found that the pump was set at 15 degrees BTDC whereas it should be set at 24 degress BTDC. Get a drip tube and measure your pump timing.

300sd2000 01-16-2004 01:05 AM

Update:

Its always whitish smoke and its NOT Moist...nor is there any loss of coolant and it has a oily smell...so I don't think its a head gasket issue.

It is most notable at warm idle and the car also shakes a little at warm idle...

Strangely, i've also noted the following:
a. adding power service cetane boost seems to help w/ reducing the smoking tremendously...however, its transient and gone by the next tank full of diesel
b. the car seems to smoke more if the fuel level in the tank is low (closer to empty).
c. adding 2 tubes diesel doctor-> increased smoke and created a loss in performance.

I don't know if algae can cause this? I use additives pretty regularly actually..

Someone mentioned timing...I've had the car for almost 13 years now and the pump has never been moved or adjusted...do I still need to worry about this? (Dealer replaced chain and tensioner about 4 years ago).

psfred 01-16-2004 11:33 AM

Injection timing is late or you have low compression. I'd adjust the valves, and check the chain for "stertch". If worn, replace. If problem isn't complete cured, adjust injection timing to spec.

Peter

ForcedInduction 01-16-2004 12:28 PM

What's "stertch"? :D

psfred 01-16-2004 08:40 PM

Stretch -- my typing is terrible.

Peter


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