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GppII
13th February 2017, 09:51 PM
Hi Mates,
I am asking for advise, I have an Y61 ZD30 DI automatic from 2000, it is powerful starts by 180° turn of the crank in -18°C, no water consumption but:
5-10 sec after start it starts to smoke white, it smells bad but I can not decide whether it is diesel or what. Once it is totally warmed up there is no smoke at all, it is running better than I would expect from a "grenade".
I've checked the CO2 by gas marker in the cooling circle: no exhaust in the coolant and it is quite clear.
I have increased the pressure on idle up by a pressurizing tool to check if there is any reaction (perhaps more white smoke if it is gasket or head) but no change.
So I believe it is not vapour in the exhaust smoke.
I have checked MAF but it was very clear, no oil residue or burned fiber from the filter.
I will make a compression measurement this week, but I do not think that this will bring any deviation to normal.
Pls. advise how to proceed further, could it be deposit on ring grooves, or injector, or the pump or what else?

happygu
13th February 2017, 10:39 PM
It may be a faulty glow plug, which would explain the smoke when the engine is cold.

I would look at changing the glow plugs anyway if they have never been changed, as they have a habit of losing the ceramic tip off the end after 150K

GppII
13th February 2017, 11:55 PM
For the compression measurement I will remove them and check. I did not know about the tip losing possibility thanks for the info, however I do not think it is glow plug, it used to smoke for a while, not only for a 30 seconds but for 5-10 minutes till it is not warmed up totally, and glow can not impact for such a long time the behavior (at least how I see).

4bye4
14th February 2017, 12:23 AM
I do not think it is glow plug, it used to smoke for a while, not only for a 30 seconds but for 5-10 minutes till it is not warmed up totally, and glow can not impact for such a long time the behavior
It could actually. If one cylinder was not firing or burning until some of the heat from the others warmed it a bit, you might blow white smoke. I did my glows a short time ago, and was absolutely astounded at the wear in them. Two of them had virtually no tip at all and the other two were at least 90% eroded, comparing them to the new ones.

threedogs
14th February 2017, 09:59 AM
My glow plugs looked like this after 200k
very hard to start IMO

GppII
17th February 2017, 07:13 AM
Hi All,
I've made a pressure leakage test on the engine via the glow plug threads, al cylinder is about 10%, gauge is calibrated.
It means that the engine is in a quite good condition. Glow plug test was performed, they are OK.
Now the injectors are at the diesel workshop to check their opening pressure and spray pattern.
I think more and more that the VP44 pump will be the guilty, I do not believe that the injectors cause the problem, I think that this is the wrong control of the injection timing advance. Via the Consult it is visible that control happens either if it is cold or warmed up, but still I have this idea in mine mind.
I would appreciate any advise or experience with this type of issue.
Thanks in advance.