Mercedes 904 commercial engine oil puzzle mystery.

Mercedes 904 commercial engine oil puzzle mystery.

Author
Discussion

Jumpingjackflash

Original Poster:

589 posts

180 months

Tuesday 3rd November 2020
quotequote all
Hello,

I own a 2015
Optare solo bus with Mercedes 904 engine with 200608 miles. The bus is using an unbelievable amount of oil.

It used 8.5L in 100 miles!

There is no leaks, the air tanks are dry, I fitted brand new turbo from Mercedes with new intercooler and cleaned all hoses etc. There is no excessive smoke from exhaust and it past emissions test last week.

The bus has low Miles, runs and sounds fine, no leaks, past emission test but I have no idea where oil could be disappearing.

Can anyone point me in the right direction to check is there an issue with these engines I’m missing?

It is a mystery.

kylos27

196 posts

99 months

Sunday 22nd November 2020
quotequote all
Is the oil the right grade (15w40)

Piston rings, breathing heavy? Oil smoke from the exhaust ?

stevieturbo

17,271 posts

248 months

Sunday 22nd November 2020
quotequote all
Jumpingjackflash said:
Hello,

I own a 2015
Optare solo bus with Mercedes 904 engine with 200608 miles. The bus is using an unbelievable amount of oil.

It used 8.5L in 100 miles!

There is no leaks, the air tanks are dry, I fitted brand new turbo from Mercedes with new intercooler and cleaned all hoses etc. There is no excessive smoke from exhaust and it past emissions test last week.

The bus has low Miles, runs and sounds fine, no leaks, past emission test but I have no idea where oil could be disappearing.

Can anyone point me in the right direction to check is there an issue with these engines I’m missing?

It is a mystery.
And as always...give us some background ?

Is this vehicle new to you ? Has it always done this, or just started ? history ?

And why did you change the turbo etc ?

E-bmw

9,242 posts

153 months

Sunday 22nd November 2020
quotequote all
Jumpingjackflash said:
Hello,

I own a 2015
Optare solo bus with Mercedes 904 engine with 200608 miles. The bus is using an unbelievable amount of oil.

It used 8.5L in 100 miles!
You are putting the oil in the engine not the fuel tank, aren't you? wink

chammyman

123 posts

113 months

Tuesday 24th November 2020
quotequote all
Why did it need the turbo changed?

Been a while since i was on the buses but the 904 is an old lump anyway.

I can only imagine its going out the exhaust despite it passing the emmisions. The DPF and CAT will catch a LOT of oil without any evidence.

Its can't be swallowing it as with that much usuage it would be running away.

If its not in the cooling system it has to be in the exhaust, and specifically via the turbo.