6.9 cam timing marks

[ramiro]

Hello,
I am still fighting with my 6.9 that is overheating and also has no real power above 4000 rpm and top speed is also only ~ 200 - 210 GPS and the idle is always a litte lumpy so my idea that maybe everything is connectet somehow.
I checked the ignition and also the fuel system and both are completly fine , so today i decided to remove the cam covers and check the timings.

All 3 timing marks ar perfectly aligned , so i decided to check the timings by checking when the intake valve on the 1 first Cylinder opens , and i found after measuring 4 times the same thing that i opens 5 Degress after TDC instead of 14 like it should be.

I measured the other side and hit is around 20 so it is retarted , actually if i would change the other 1 toth both cam shafts should match.

Has anybody checked their timing marks on a 6.9 if they are correct ?
I spoke with an engine builder and he told me that he had mercedes engines where the mark was of by half a teth.
Thank You
Ramiro

[daantjie]

Maybe post pics of your timing marks.  It's been a while since I looked at this stuff but as I recall the driver side (LHD) cam must line up with damper mark at 0.

There are offset keys available to finesse the timing. Do a search I'm pretty sure some members have run into this issue.

[raueda1]

Some cam mark pix HERE with a lot more details on cam timing.  Might be helpful....  Cheers,

[rumb]

Are you following procedure 05-215 in the 100.985 engine manual to check valve opening? It mentions valve lift of 2mm when checking.

[ramiro]

Yes i followed 05-215 exactly also changed to lifter to manual adjustable ones.
My marks are exatcly centered , i would even say that in the other thread on mark is 0.1 mm off that my isn't.
I retarted the passenger side cam 1 tooth but now it seems to be at ~ 28 after tdc also far away from spec(14 at 2 mm intake valve lift) i don't know why it is not at around 20 because 5 + 18(1 tooth) should be 23 not nearly 30.

One more thing when i got the car the same cam that is now out off adjustment was 1 tooth off the timing mark and i corrected(but only checked the mark not the actual timing) it suspecting that i found an issue but now it seems that it was maybe more correct.

EDIT:
I rotated the engine 1 more around with the chain tensioner in place and now it is around 25 also when on the mark it shows 15 Degress off same like when i got the car , this setup actually makes much more sense it would mean that my chain is stretched around 6 - 8 degress one the driver side and around 10 -12 on the other , but i still don't understand why the mark is not matching ?

[rumb]

Im a bit confused by some of your statements.

"All 3 timing marks are perfectly aligned"
and
"my chain is stretched around 6 - 8 degrees on the driver side and around 10 -12 on the other"


With 10-12 stretch (that is the spec limit) it seems to be time for a new chain. It's normal for each side to be different on an older engine.  Even MB expects ~4 degrees stretch after 20K.If 
you use keys at some point it wouldnt hurt to add a degree or 2 initially.

BTW on my 300se a new chain I could definitely feel better power.

[ramiro]

Ok to make it clear :
All timing Marks aligned :
Driver side (left) intake valve opens(2mm) ~ 20 after TDC
Passenger side(right) intake valve opens(2mm) ~ 5 after TDC

Passenger side one toth retarded and timing mark for that cam aligns at 15 degress after tdc on the crankshaft:

Driver side (left) intake valve opens(2mm) ~ 20 after TDC
Passenger side(right) intake valve opens(2mm) ~23 after TDC

So i am really confused if mercedes machined the groove for the camshaft gear wrong on 1 cam

[ramiro]

To be sure i confirmed the measurments again today (0.1 mm vavle could already make a degree difference) and got the same like yesterday 23 right side and 20 left side.
So should i correct it using the special wedges or use a new chain normally i would think that the chain is somehow worn to the gears and it would be better leave it in ?

Attached some pictures from the results.
I set the dial at exatctly at 3 mm on when the valve was closed , so you can see it went exactly 2 mm.

[rumb]

So if spec is 14 and you are now at 20 and 23, that means you are off by 9. 10 is the limit, so I would pull a new chain in. Assuming your guides are fine the gears should be also, though look close at the cam gears at least. Those are easy enough to replace if needed.

[ramiro]

Just wanted to give a feedback , i put the chain in and enjoyed the car for 3 weeks now , the car drives much much better has really got power above 4000 now and the idle is sometimes smooth never got that before

Different fight was the CIS 2 months ago i suddenly had huge trouble with the CIS doing whatever it wants sometimes rich sometimes lean changed the fuel distributor and did not change much , put injector cleaner in the tank and it got much better with the previous distributor that i bench tested before, but still not perfect , so today i decided to change the 2 year old MANN fuel filter and it turns it had dissintergrated inside and put all the dirt into the system , never had that before.

The new chain ended up with 10 (as spec for a new chain) on the passenger side , and 16(should be 12 for a new chain) on the driver side.

[daantjie]

Pretty sad that once great manufacturers are now also producing garbage.  Just look at how bad Bosch has gotten over the years

[ptashek]

I exclusively use Mann, and their secondary brand filters in all my cars since I had cars. Many, many moons at this point.

Haven't had a single issue. Ever. There's always a chance of something slipping through QC in a batch. I wouldn't discard the entire brand as garbage based on a single case.

And they absolutely deserve credit for still making fresh filters for 40+ year old cars too

[ramiro]

Crazy what a difference the cam timing makes , before the car refused to go faster then 220 on the speedometer now on a semi flat autobahn it goes to 240.
Also attached a picture of the broken filter , and it defintive was loose before i opened it, because i could hear it moving around inside when i was shacking the filter.

[ptashek]

Looks like that filter was due for replacement years ago.

[ramiro]

Years ago that Filter was not even made , i bought that filter in Dezember 2020 and drove 20000 KM with it , or is the interval 1 year and 10000 km ?
The metal cap that was glued on was already off before it took the filter apart for me it looks like the glue failed.