Oil Catch Can on OM642 engine ?

[joderest]

tried that

 

[Peter Taplin]

Hi all
First time poster here on the forum, I seem to have had most of the normal problems with my OM642 in a 2006(late) GL320 with 320K on the clock so I thought I would share the issues and solutions so far with you.
The first time apart was for a swirl flap issue, when I pulled it all down it became apparent there was large quantities of oil and carbon in the intake.
I removed the swirl flaps tapped the shaft holes and blocked them with bolts.
Once cleaned and reinstalled I used a resister on the plug for the swirl flap motor to fool the ecu. cleared the codes and all was good for the next 40k although the economy was down about 1L per100k.
The next time apart (40k on) was for an oil leak at the cooler, when stripped the amount of crap in the intake was diabolical, 4mm thick.
There had always been oil around the turbo inlet and crankcase vent so I decided to block the EGR and catch can the crankcase.
I also had a broken air intake pipe on the batwing where it attaches to the turbo.
So I machined up an aluminum adapter then slid inside the batwing, cut the broken plastic off and pushed the adapter in. then by cutting down the turbo seal (orange) and putting that on the turbo the adapter seals without air leaks. After checking the seal the aluminum adapter was bonded to the plastic. I was looking at having to buy a new batwing so this fix was a great way to solve the problem.
I used a twin catch can system that uses baffles and coarse scourers to separate the oil from the vapor.
The car has now completed approx 5000k in this configuration and other than the egr throwing a trouble code its a different car.
8-9L/100k blows no smoke and the tailpipes are clean for the first time.
I have removed the batwing to check for oil in the intake and its clean.
The next step is to defeat the egr fault code which I should have done next week.

Thanks to all the posters on the forum as they have been an invaluable resource in my quest to sort this car out.

 

[kid-jensen]

Good post, looks like you're on top of all the normal OM642 problems.

Why not try marketing the aluminium adaptors? I'll bet they would sell well on ebay...

How (and where) did you mount the Catch cans? Did you just take the feed from the Crankcase breather?

 

[Wighty]

Hi all
First time poster here on the forum, I seem to have had most of the normal problems with my OM642 in a 2006(late) GL320 with 320K on the clock so I thought I would share the issues and solutions so far with you.
The first time apart was for a swirl flap issue, when I pulled it all down it became apparent there was large quantities of oil and carbon in the intake.
I removed the swirl flaps tapped the shaft holes and blocked them with bolts.
Once cleaned and reinstalled I used a resister on the plug for the swirl flap motor to fool the ecu. cleared the codes and all was good for the next 40k although the economy was down about 1L per100k.
The next time apart (40k on) was for an oil leak at the cooler, when stripped the amount of crap in the intake was diabolical, 4mm thick.
There had always been oil around the turbo inlet and crankcase vent so I decided to block the EGR and catch can the crankcase.
I also had a broken air intake pipe on the batwing where it attaches to the turbo.
So I machined up an aluminum adapter then slid inside the batwing, cut the broken plastic off and pushed the adapter in. then by cutting down the turbo seal (orange) and putting that on the turbo the adapter seals without air leaks. After checking the seal the aluminum adapter was bonded to the plastic. I was looking at having to buy a new batwing so this fix was a great way to solve the problem.
I used a twin catch can system that uses baffles and coarse scourers to separate the oil from the vapor.
The car has now completed approx 5000k in this configuration and other than the egr throwing a trouble code its a different car.
8-9L/100k blows no smoke and the tailpipes are clean for the first time.
I have removed the batwing to check for oil in the intake and its clean.
The next step is to defeat the egr fault code which I should have done next week.

Thanks to all the posters on the forum as they have been an invaluable resource in my quest to sort this car out.

Welcome to the forum , that’s some great work , post some pictures if you get the chance

 

[Larkone]

Good post, looks like you're on top of all the normal OM642 problems.

Why not try marketing the aluminium adaptors? I'll bet they would sell well on ebay...

How (and where) did you mount the Catch cans? Did you just take the feed from the Crankcase breather?

Already one out there - though not allly
https://turbozentrum.co.uk/Repair-Kit-Intake-Mercedes-Benz-30-V6-CDI-OM642

 

[Peter Taplin]

Thanks for the comments and some pics attached
From experience of modifying cars over the years I generally use a temporary fix to make sure it works before finalising and improving the design, hence I have cut the breather tube and taken hoses from there to the catch can mounted near the rhs headlight. I have used 13mm hose to connect the catch can to the breather. The catch cans are currently collecting the oil but will be set to drain back to the sump. It has created a small amount of pressure in the crankcase under high load but it is only a very minor increase(less than .5psi) when I measured the crankcase pressure before this it was approx .4psi. I note that a number of people who have fitted catch cans have experienced water in the oil collected in the catch cans, this is not a phenomenon I have experienced yet. This may be related to a number of things, the car is used mainly for highway use and the shortest trip is 80k and a normal trip length is 300k, the position of the can and being aluminum may be evaporating off any water vapor and returning it to the turbo inlet.
Using a larger catch can (larger inlets and outlets) of 19mm or so would be better than what I have done so the next step is to change out the cans now I know it has worked for a better can. Also machining up a fitting for the cam cover to take a 19mm hose and removing the plastic valve. that valve has me a little perplexed as I can see no real purpose to it so I will remove it and se what happens, surmising that it may close under certain conditions ie suction from the turbo to prevent oil being sucked out of the engine is my best guess.. any thoughts anyone?

 

[Wighty]

Thanks for the comments and some pics attached
From experience of modifying cars over the years I generally use a temporary fix to make sure it works before finalising and improving the design, hence I have cut the breather tube and taken hoses from there to the catch can mounted near the rhs headlight. I have used 13mm hose to connect the catch can to the breather. The catch cans are currently collecting the oil but will be set to drain back to the sump. It has created a small amount of pressure in the crankcase under high load but it is only a very minor increase(less than .5psi) when I measured the crankcase pressure before this it was approx .4psi. I note that a number of people who have fitted catch cans have experienced water in the oil collected in the catch cans, this is not a phenomenon I have experienced yet. This may be related to a number of things, the car is used mainly for highway use and the shortest trip is 80k and a normal trip length is 300k, the position of the can and being aluminum may be evaporating off any water vapor and returning it to the turbo inlet.
Using a larger catch can (larger inlets and outlets) of 19mm or so would be better than what I have done so the next step is to change out the cans now I know it has worked for a better can. Also machining up a fitting for the cam cover to take a 19mm hose and removing the plastic valve. that valve has me a little perplexed as I can see no real purpose to it so I will remove it and se what happens, surmising that it may close under certain conditions ie suction from the turbo to prevent oil being sucked out of the engine is my best guess.. any thoughts anyone?

View attachment 55407 View attachment 55408

Good work , there is an updated pcv breather tube available from MB that is available , may be worth changing if yours is original .

 

[kid-jensen]

I'm probably being thick here..
I can see the hose coming from the Crankcase vent (PCV) but no return back to the inlet.

Am I missing something?

 

[Larkone]

Good work , there is an updated pcv breather tube available from MB that is available , may be worth changing if yours is original .

Agreed - the rubber diaphragm goes hard and splits with age and heat. Improved orange seal on the end as well. Mine was split and ran much better after replacing.

 

[Wighty]

I'm probably being thick here..
I can see the hose coming from the Crankcase vent (PCV) but no return back to the inlet.

Am I missing something?

There are no pictures of that return , but there are two red catch cans which are linked together , and you can see the two grey pipes , one from the pcv and one back to the pcv pipe before the turbo inlet (which is the second pic with the electrical connection above the small red pipe)

 

[Peter Taplin]

 

[Peter Taplin]

Here's a pic of the temp return lines, should have the new catch can and 19mm lines installed later this week with the diaphragm unit removed and new fitting into the cam cover., I will load some more images then.
Been using a KESS and ECM Titanium to access the ECU today, its going to take some time to work it all out but so far I have turned off the EGR by changing the expected air volume from the EGR as registered by the MAF sensors to zero. also upped the boost by 2 psi and altered the fuel on cruise to run a little leaner.
good results so far, I cannot seem to access the throttle mapping so I can remove the soft throttle feel, if I can work this out it should be good to drive.
Once the ECU is reprogrammed and runs the way it should it may be good to access the gearbox tables using a KTAG and bench mount the ECU as this is the only way to make changes to the transmission tables.

 

[oigle]

Here's a pic of the temp return lines, should have the new catch can and 19mm lines installed later this week with the diaphragm unit removed and new fitting into the cam cover., I will load some more images then.
Been using a KESS and ECM Titanium to access the ECU today, its going to take some time to work it all out but so far I have turned off the EGR by changing the expected air volume from the EGR as registered by the MAF sensors to zero. also upped the boost by 2 psi and altered the fuel on cruise to run a little leaner.
good results so far, I cannot seem to access the throttle mapping so I can remove the soft throttle feel, if I can work this out it should be good to drive.
Once the ECU is reprogrammed and runs the way it should it may be good to access the gearbox tables using a KTAG and bench mount the ECU as this is the only way to make changes to the transmission tables.

Feasible on a petrol engine but not on diesel. Diesel engines have unlimited air. If you reduce the fuel, you will simply reduce the power being produced and go slower. No gain there.
I had to remap my ecu for more agressive initial fuel input to get away from the "soft throttle" as you called it. To me, it was a bad and dangerous flat spot on initial "off the mark" throttle.