OM606.910 cam timing enigma - Page 3 - PeachParts Mercedes-Benz Forum

spock505 · #31 06-16-2017, 12:38 PM

..you have to be kidding..lol

Went out this morning after ordering the remaining gaskets/bits bobs fully expecting to hear that noise, only worse as now cold..but..

Probably best you listen..

First video from cold (ignore oil level light as faulty)

https://youtu.be/80FETpmOtPc

After 5 minute drive (summer here, so reaches temp quickly)

https://youtu.be/3NqbAQl-jmY

A little way through (24 secs) you can hear a bearing noise, aware of this, either w/pump or alternator (possibly).

The down pipes although stainless are a lot less meaty than those removed, this doesn't help but the noise is barely audible.

spock505 · #32 06-17-2017, 11:59 AM

Started stripping the 962 ready for swap over, only visual differences so far related to the two sensors on 910, 962 has one port plugged.

Checked cam timing, 1 degree of stretch which looks promising - quick question, the 962 has a clutch type alternator, can this be swapped with non clutch type?

Checked EPC but there's a lot of upgrade notes to make sense of.

Just waiting on water pump gasket to swap that out too (assuming same).

spock505 · #33 06-20-2017, 09:23 AM

962 head removed, any tips for getting rid of metal fragments caused by exploding bit.

It's the top right bolt in this photo which is next to a valve spring, might have to pop the valve out to make sure clear.

I'll check the brand of spline bit, but I know it wasn't cheap - for those reading from Blightly, ended up using their Advance 1/2 drive socket splined bit.

Maxbumpo · #34 06-21-2017, 09:03 AM

Quote:

Originally Posted by spock505

962 head removed, any tips for getting rid of metal fragments caused by exploding bit.

Run a magnet around? Lay the head in a big pan, spray down with WD-40 or brake cleaner, rinse the fragments down into the pan? Last resort, power wash it at the local car wash.

Maxbumpo · #35 06-21-2017, 09:05 AM

What's the plan for the new head?

I can hear the noise in the video, hard to know what that is without more diagnosis. Are you thinking that is a bad valve or something else wrong in the valve train?

How about sending a used oil sample for lab analysis, that may tell you what metals are too high, which can sometimes pin point the failure mode (bearings or rings).

spock505 · #36 06-21-2017, 10:05 AM

Cheers Max, magnet picked up most of the frags but worried about inner area and base of spring, ended up removing one of the valves.

Refitting valve, is orientation important (marked head/valve) or do these rotate during use?

Not sure what the issue is with 910 head, it was sent to machine shop a while back (see pre-chamber pics) - need to verify TDC for a clean base line and go from there.

Should be able to pull 910 tomorrow all being well, flipping hot here - has to be 35c ..I know..Arizona..is like melting the sand or something..but it's hot for us Brts

spock505 · #37 06-23-2017, 09:33 AM

910 head pulled today, very quick look over reveals one of the inlet valves completely sooty as opposed to the others which are mostly clean.

The odd pattern maybe caused by water injection on the inlet side, certainly the inlets from the 962 with no wi are equally sooty.

I need to check the crank timing next but first need to clear up the (extensive) mess first

spock505 · #38 06-24-2017, 04:06 PM

Bit of an update today, started by checking timing visually using number one cylinder of injection stroke, all good within 1-2 degrees but will use a gauge once ready to bolt up again.

Timing market OT

Number one cylinder

Cross hatching still present but notice extra grey carbon deposit band

This extra band can be seen better in this picture

This is the 962 block (W210) with much smaller band

910 with perhaps half inch below the dark carbon marking

910 valves removed for inspection, using a power drill each one is a slightly off center but this could be the chuck bit

Glow plugs came out with ease showing no signs of blow-by, one however is corroded

spock505 · #39 06-26-2017, 10:28 AM

Replacement alternator fitted, it is big with the larger plastic cowl touching the block cooling hose - will monitor to see how that goes, may need to put an elbow in there.

Question, cylinder 1 on the 910 has the ,marking '10' on older engines this used to signify over sized pistons following re-bore, is this likely or just MB quirk?

Inspected the band mentioned earlier, this looks like the steam tackling the carbon build up turning it grey, there's also small parts where it has managed to expose the cylinder underneath.

Made a small glow plug reamer tool which worked well, unusually the 962 had one stuck plug (2nd from back) which was very sooty -

It will be interesting to see if the w-i keeps the carbon at bay helping ease future glow plug removal.

spock505 · #40 07-02-2017, 11:41 AM

Hi folks, just in the process of sorting out the water pump and housing whilst in bits, quick question -having removed both water pumps from 962 and 910 itemizing respective bolts, I now notice there are only five but seven holes?

Something else bolts on taking up the two free bolt holes but cannot think what, FSM is no help either just listing bolts and torque settings.

Any pics of your own pumps or tips welcome.

Thanks,

spock505 · #41 07-10-2017, 02:46 PM

All back together today, very pleased with the outcome as the engine note has changed considerably although there is till a very slight ticking noise.

In summary, I reset the timing using a level gauge followed by the injection pump, both were within 2 degrees of spec which is a lot better than before.

Parts changed:

Cylinder head, cam housing, cams and cam caps, cam drive sprocket, chain guides.

Injectors (new)

Glow plugs

Fuel heater, larger bore so needs new piping.

Water pump (the 962 is off concentric which broke housing, temp JB Weld until new one arrives)

Alternator, 115 amp

Belt pulley assembly.

All new gaskets throughout.

As mentioned, there is still a slight ticking noise which is hardly noticeable but may as well sort that too, could it be the vac pump?

spock505 · #42 07-21-2017, 03:42 PM

Last post to wrap up the thread which had it's ups and downs but has been ultimately worth while.

Engine has settled down now, very quiet and soft if that makes sense, absolute pleasure to drive - added bonus the oil level light now works too, no idea why changing the head would make a difference but it extinguishes as normal.

Other bonus parts, higher capacity alternator and improved fuel heater with large inlet bore, no more air -

Internals, you get the added benefit high temperature kryptonite exhaust valves, this may include the seats also (not checked).

Getting a replacement water pump housing sounds easy right, nope most of the second hand parts corrode around large hose connections - MB only do exchange units with the replacement needing some JB Weld to smooth out milled surface.

The other bonus is my lovely neigbours who helped lower the new head onto block, absolutely amazed the thing works let alone drives after being a pile of bits

(again)

Maxbumpo · #43 07-21-2017, 04:05 PM

Congrats, very satisfying when you reach the end of such a huge project.

spock505 · #44 07-21-2017, 04:22 PM

Cheers Max, must admit to holding my breath when first starting just in case there were subtle differences 962 v 910 - all good though, lots of parts can be interchanged too (except water pump, lol)

One thing I didn't mention when inspecting the 962 head was a huge lump of swarf sitting behind the rear water jacket exit, it my have broke up trying to pull it through the hole - if anyone is doing an engine flush possibly something to look out for.

spock505 · #45 07-22-2017, 10:08 AM

Didn't have a photo handy yesterday, but wanted to post a pic of the two water pumps for reference - they look very similar and indeed the gaskets fit both, but the 962 to the left is off center causing it to hit the outer casing.