Sprinter 311 oil leaking through dipstick

[Sprinter]

Hi all

We're new to this and looking for some advice please.

2007 sprinter 311 cdi lwb, started leaking oil smoke etc. Called green flag, taken to garage who advised the dipstick was loose and oil leaking up through that. Advised to replace dipstick.

Ordered new dipstick from mb, doesn't fit, but after talking to people they seem to suggest that the amount of oil coming up through the dipstick means the piston rings have gone.

Is this likely and if so what are the options, or could it just be a faulty dipstick or something else.

Many thanks in advance for any assistance you can offer.

[BlackC55]

If there is oil coming up the dipstick it means there is crank case compression which normally means the rings are worn.

Very unusual on an MB engine. Has it got mega miles? Is it ssrvice at the correct intervals with the correct oils?

[ched999uk]

It does sound like a rings issue that is increasing the crank case pressure. You can see if the crank pressure is excessively high by taking off the oil filler cap when the engine is warm and running and seeing if you can feel air coming out on your hand. Be a bit careful as it might be hot.
The rings may nor actually be worn they may just be pinched. What can happen if cheap oil or extended service intervals are used is that carbon builds up in the grooves on the pistons and eventually jams the piston in the ring. This causes very poor sealing and high crank case blow by.

On a few occasions stuck rings can be freed by a good engine flush with good quality flushing oil. This can on the odd occasion free the rings as it contains a high level of detergent. To be honest flushing is a bit of a long shot but maybe worth a few quid and an hour of your time.

Good Luck.

[Sprinter]

Hi thanks for the reply. It has done just over 200k miles, but serviced regulary just independent after the first 2 years.

Stuck really on what to do next.....

[CRASH67]

to be honest pistonrings on 646 are unheard of.
the only issues that am aware of on the Sprinters are oil seperators/breather (there was a recall on some check with you dealer that can check reg numbers)
and there was the occasional sump gasket

And very rare issue of sprinters "making oil"

[BlackC55]

I would try a flush out first just to see if that helps.

[Will]

Might be worth doing a cylinder leakdown test to check if the rings/bores are letting by?

If the bottom end is tired it might be worth looking for a good used engine to replace.

Will

[CRASH67]

id even try contacting your dealer and try and seek some advice,
unlike car dealers you find some if not most commercial dealers are different world to cars and may even chat with and give you a few routes too look it to, allways worth asking

[CRASH67]

Originally Posted by Will

Might be worth doing a cylinder leakdown test to check if the rings/bores are letting by?

If the bottom end is tired it might be worth looking for a good used engine to replace.

Will

if you go that route make sure you get a Sprinter engine from anew shape ie OM646

altho a new with you engine in exchange will cost 5k mark with a 2 year warranty

[Sprinter]

Thanks again for all the advice - are the flush and leakdown tests easy to do?

[CRASH67]

phone your Merc dealer and check if its due for a recall on the oil sperator as if the oil sperater fails it can cause pressurising in the crankcase hence your issue,

[CRASH67]

MERCEDES BENZ Recalls the Sprinter (Mar 2010)


Fire may occur

MERCEDES BENZ announced a problem with the Sprinter affecting a total of 8,064 vehicles.

It has been identified that, the fleece filter insert of the engine oil separator may become obstructed with dirt particles. It is therefore possible, that an increase in pressure within the crankcase may occur with the result that oil could escape onto hot engine parts. Should this occur, a fire may ensue. Vehicles built from 1/1/2006 to 12/31/2008 are at risk.

Recalled vehicles will have the original oil filter replaced with one of a cyclone type.
If you think that your vehicle may be affected by this recall you should contact your nearest MERCEDES BENZ dealer who will be able to confirm whether or not your car is safe and arrange its repair if necessary.

after some googling found this ^ on the oil sperator i work for a dealer and knew we done this recall alot but as parts man only supply parts so never know exactly why.
but this give you an idea

If runs on Sprinters 06 to 09 with a 646 engine a dealer can use your reg to see if you van was one due for the recall failing that id say its a fair chance you will require the part either way but check to see if yours is one of the effected

[BlackC55]

Originally Posted by CRASH67

MERCEDES BENZ Recalls the Sprinter (Mar 2010)


Fire may occur

MERCEDES BENZ announced a problem with the Sprinter affecting a total of 8,064 vehicles.

It has been identified that, the fleece filter insert of the engine oil separator may become obstructed with dirt particles. It is therefore possible, that an increase in pressure within the crankcase may occur with the result that oil could escape onto hot engine parts. Should this occur, a fire may ensue. Vehicles built from 1/1/2006 to 12/31/2008 are at risk.

Recalled vehicles will have the original oil filter replaced with one of a cyclone type.
If you think that your vehicle may be affected by this recall you should contact your nearest MERCEDES BENZ dealer who will be able to confirm whether or not your car is safe and arrange its repair if necessary.

after some googling found this ^ on the oil sperator i work for a dealer and knew we done this recall alot but as parts man only supply parts so never know exactly why.
but this give you an idea

If runs on Sprinters 06 to 09 with a 646 engine a dealer can use your reg to see if you van was one due for the recall failing that id say its a fair chance you will require the part either way but check to see if yours is one of the effected

Thank you for this info. I get most PC stuff but not CV.

[CRASH67]

Originally Posted by BlackC55

Thank you for this info. I get most PC stuff but not CV.

well i work with Cv stuff TBH the engines the vans diesel wise are almost the same anyways lol

[Sprinter]

Thanks I had just found that on google too, thought they would have told me though, haven't moved or anything since buying the van new from local dealer. Will get on to them 1st thing.

Thanks again