Diesel Gurus... Help.

[Monique]

Hello experts,

We took delivery of Star Gal (our nickname for her... short for Battle Star Galactica) yesterday. A '99 W210 220 CDI Touring, it is the vehicle we needed. MANY high way kms, it does not ride or feel like a 292,500 kms car. No squeeks, rattles or annoying perks. Well cared for by the PO. No rust either.

While inspecting the engine, I note a deposit at the injectors. This is like creosote (the deposits forms inside your chimney if you burn wet wood)(also can be described as a tar like substance) There is no leakage at the moment as all injectors have been rebuilt or changed.

I began cleaning away the mess today but ran out of thinner... engine degreaser did not work.

Q1: What causes this type of deposit?? How can I avoid it in the future?

Q2: A large quant of Diesel system cleaner was added. I started the car and let it idle for 25 minutes to fiddle with the nav system. At one point, I goosed the engine to 4K and blue hazed the neighbourhood. 10 secs later no more smoke and no more since even after vigorous goosing. The engine runs too well to need rings. What caused the blue smoke?

I know.... pics are forthcoming...

 

[GazCaff]

The blue smoke may have been caused by the crank-case breather filling the inlet tract up with oil droplets/vapuor which was only cleared when you gunned the engine. This is quite feasable given the length of time you had it idling and I wouldn't worry too much about it.

 

[markheaney2]

this is common on this engine it is called the black death it all needs to be cleaned off and usually you have to take the injectors out and clean them up as well the signs of black death are noisy injectors that tinkle like injector knock

 

[Dieselman]

The injectors are blowing combustion gasses past the seals. Remove the injectors (can be a chore), fit new seals and sealing compound and refit the injectors.

You might need to soak the injectors in Coka-cola to dissolve the built up coke deposits.

 

[Monique]

Coca Cola? Is this a trade mark?

I will begin with a cleanup... then I will follow your suggestion, Dieselman.

Thank you. All of you.

I am quite mechanically minded and contribute to forums of different makes... soon, I should start offering some thoughts on our Mercs (misguided??)