Start up smoke andcarbon splatter?

[Wizard52]

Hi all

As we all know, the old 4.2TD's blow a bit of smoke on start up and is nothing to worry about.
However, recently mine also blows either carbon or extra diesel out of the exhaust as well as the normal smoke. It leaves a small- about 10cm wide and about 20cm long splatter on the cement which is not easy to remove. I don't touch accelerator at all.
It has only started after a trial of 2 stroke at 200 to1 for both tanks and when almost empty the current tanks with Chemtech additive.
Probably my imagination but motor seems a bit louder when idling and cold. Performance is normal,, boost and EGT's normal and fuel consumption seems ok but as I had another trip over to the Island last weekend, it will take another tank full to confirm.
Any thoughts?

[threedogs]

It may need a decent high speed run to burn to gunk out of it.
It may just be carbon build up in the exhaust

[Cuppa]

Since I’ve had a nice clean concrete surface in the new shed to park in I’ve noticed the same thing with mine (grrrr) but not on every start. I’m thinking along the lines TD has suggested, that maybe it’s more likely if the last time the vehicle was started it got switched off before it got fully warmed up. Only a theory at this stage.

[Bush Ranger]

Try with out the additives and or a longish run as suggested by TD.

[Wizard52]

It may need a decent high speed run to burn to gunk out of it.
It may just be carbon build up in the exhaust

Hi TD
Was over on Fraser for a few days mid June and had a bit of hard work in loose sand from Indian Head to Waddy but not all that hard I suppose.

Will go and flog it up a long hill (about 1.5klm) in lower gears a couple of times. That is where I check EGT's and boost are normal as I'm doing 100kph by time I'm a third of way up.

[threedogs]

Hi TD
Was over on Fraser for a few days mid June and had a bit of hard work in loose sand from Indian Head to Waddy but not all that hard I suppose.

Will go and flog it up a long hill (about 1.5klm) in lower gears a couple of times. That is where I check EGT's and boost are normal as I'm doing 100kph by time I'm a third of way up.


A nice steady trip sitting 100KPH or 110 KPH what ever is your limit up in Qld..
You dont want to be blowing black smoke going up a hill , thats defeating the
reason of what you are trying to acheive