Troubleshooting white smoke from an OM617 - Page 2 - PeachParts Mercedes-Benz Forum

CenCalBenz · #16 11-10-2011, 12:03 PM

Quote:

Originally Posted by kerry

It would be very helpful if you posted a video. A recent smoke issue was properly diagnosed after a youtube video was linked to the thread.

That is a good idea. Ive gotta find something around the house that is worth while recording with.

Quote:

Originally Posted by whunter

Note:
Cam lobe angle for each valve being adjusted is critical.
Valve adjustment OM615, 616, 617 FYI.

If the valve adjustment was put off to long:
Carbon builds up on valve and seat = the valves must be adjusted multiple times with an Italian Tune-up between each adjustment.

Three adjustments on the same engine within one day is not unusual for a poor maintenance vehicle.

You should only need to be this intensive "once" with an unknown maintenance vehicle.

.

Right, the cam lobe, smaller side up at roughly 90*. Ok so I will do an italian tune up, find some big hills etc, then adjust the valves again. SOUNDS LIKE FUN!

That carbon building up on the valve seat sounds like a pretty good theory to me. Some of the valves were incredibly tight too.

The who ever had owned this car before me ran what ever they thought was "bio-diesel" in it, so I figure what ever crappy grease they got that Benz to mull on put some deposits in the engine.

kerry · #17 11-10-2011, 12:04 PM

Smoke going away and then coming back doesn't strike me as a valve problem. Wouldn't a valve problem be more consistent?

CenCalBenz · #18 11-10-2011, 12:07 PM

Quote:

Originally Posted by kerry

Smoke going away and then coming back doesn't strike me as a valve problem. Wouldn't a valve problem be more consistent?

Even if it is in correlation with the warming up of the engine? Once it has been driven hard it clears up after awhile. I have let it set before after driving it hard and it started to smoke again.

I will make a video of that happening.

With out a doubt the injectors will get some tlc though. I found a set of new Bosch nozzles for $100.

kerry · #19 11-10-2011, 12:15 PM

What temperatures are you seeing on the t emperature gauge during these variations? It doesn't take much heat to get rid of incomplete combustion as a result of a cold start.

CenCalBenz · #20 11-10-2011, 12:21 PM

Quote:

Originally Posted by kerry

What temperatures are you seeing on the t emperature gauge during these variations? It doesn't take much heat to get rid of incomplete combustion as a result of a cold start.

If memory serves, I think above 170 to no more than 210.

I never even really thought about it, but I may have a glow plug out. It always fires up after 30 seconds of application of the glow plugs.

CenCalBenz · #21 11-10-2011, 12:29 PM

I am starting to think that this is a combination of problems. Like stated, there maybe carbon build up on the valve seats and the injectors are coked up and or worn out. I think new nozzles and another valve adjustment is definitely in order.

kerry · #22 11-10-2011, 12:34 PM

Quote:

Originally Posted by CenCalBenz

The who ever had owned this car before me ran what ever they thought was "bio-diesel" in it, so I figure what ever crappy grease they got that Benz to mull on put some deposits in the engine.

That could be the cause of your problems.

whunter · #23 11-10-2011, 04:26 PM

Quote:

Originally Posted by CenCalBenz

Right, the cam lobe, smaller side up at roughly 90*.

Ok so I will do an italian tune up, find some big hills etc, then adjust the valves again. SOUNDS LIKE FUN!

That carbon building up on the valve seat sounds like a pretty good theory to me. Some of the valves were incredibly tight too.

The who ever had owned this car before me ran what ever they thought was "bio-diesel" in it, so I figure what ever crappy grease they got that Benz to mull on put some deposits in the engine.

Never a 90° on the cam lobe.

Look at the attached picture.

.

CenCalBenz · #24 11-10-2011, 10:23 PM

Quote:

Originally Posted by whunter

Never a 90° on the cam lobe.

Look at the attached picture.

.

Hmm, thanks for pointing that out.

I went by the diesel giants website's valve adjustment article.

Mercedes Diesel Valve Adjustment Procedure

It states "Get the number 1 cyl camshaft lobe pointing straight up, 90 degrees relative to the adjusting pad just like shown in the picture. To your eye this will look like the lobe is in about the 1 o'clock position. Never try to adjust the valve with the lobe in any other position than pointing this way."

Can it cause a large difference in the tolerances?

whunter · #25 11-11-2011, 12:15 PM

Quote:

Originally Posted by CenCalBenz

Hmm, thanks for pointing that out.

I went by the diesel giants website's valve adjustment article.

Mercedes Diesel Valve Adjustment Procedure

It states "Get the number 1 cyl camshaft lobe pointing straight up, 90 degrees relative to the adjusting pad just like shown in the picture. To your eye this will look like the lobe is in about the 1 o'clock position. Never try to adjust the valve with the lobe in any other position than pointing this way."

Can it cause a large difference in the tolerances?

YES.
Especially on an engine with heavy carbon built up on valve and seat.

I respect "dieselgiant", but we have disagreed on this point for years.

MB is extremely specific regarding correct cam shaft lobe angle, and spent massive $$$$$$ + thousands of design/engineering/development man hours getting it right.

My Professional experience in the field has shown that following the MB angle gives better performance for a longer time.

leathermang · #26 11-11-2011, 02:22 PM

I can not figure out what the difference is between yall's description..
Yes, DG used the words ' straight up ' but modified that to what I think is correct as to being ' one oclock' position..' .... and the ninety degrees from the pad seems to be what I remember as the FSM instructions..
Have I failed to read what is important and different ?
I do NOT respect Diesel Giant due to his promoting ( always failing to mention problems with ) junk refrigerants.... so I would love to side with Whunter on this and anything else... but I can't find the real point of contention...

jab0028 · #27 11-11-2011, 03:19 PM

Is it possible that either the ip diaphragm or vacuum pump diaphragm has a tear in it?

leathermang · #28 11-11-2011, 05:52 PM

Quote:

Originally Posted by CenCalBenz

... it clears up after awhile. I have let it set before after driving it hard and it started to smoke again. .....

THAT is a classic symptom of worn valve stem seals.....

If that is the problem... it is cheaper and easier than some of these other potential fixes.....

whunter · #29 11-11-2011, 11:31 PM

Quote:

Originally Posted by leathermang

I can not figure out what the difference is between yall's description..
Yes, DG used the words ' straight up ' but modified that to what I think is correct as to being ' one oclock' position..' .... and the ninety degrees from the pad seems to be what I remember as the FSM instructions..
Have I failed to read what is important and different ?
I do NOT respect Diesel Giant due to his promoting ( always failing to mention problems with ) junk refrigerants.... so I would love to side with Whunter on this and anything else... but I can't find the real point of contention...

The issue is valve adjustment angle for camshaft profile OM615, 616, 617.
Picture attached to illustrate.

The junk refrigerant issue bothers me, but it is a personal decision for each vehicle owner.
Not something for me to get stressed over...

IMO:
Respect for his efforts to document DIY procedures is justified.
It does NOT mean I agree with every word.
He and I have talked, and agree to disagree on some topics without malice.

leathermang · #30 11-12-2011, 12:06 AM

He screwed up a couple of other things too...
The FSM forbids using the power steering nut to turn the engine ... it is a taper fit for that pulley... thus over tightening it... which by definition you have to do trying to turn over a diesel compression engine with it... will spread the inside of the pulley... as compared to just mashing harder on it..
And that crap about using the lower nut as the adjusting nut... that is nutty too.... if you really did that you would be risking striping the threads on the valve... meaning you would have to take the head off to fix the situation..

The fact was that he was like another dealer... he SOLD Duracool or whatever.... and promoted it without telling the whole picture... never mentioning the downsides.... which I do not think is fair to forum members...