The trick to the game is not to end up in "the abyss".

To avoid this fate requires that you always keep upward tension on the camshaft sprocket. This is best done with bungee cords and an overhead beam.

When the head is first lifted off the block (get an engine hoist), you shove some welding wire through the chain at the very top of the block to prevent the chain from falling. Naturally, you must unhook the bungee cord to get the head over the top of the camshaft sprocket. The welding wire prevents the chain from falling into the abyss at that time.

The abyss also is fond of grabbing two of the four small cap screws that secure the front of the head. Two of them are inside the timing chain cavity, and one mistake, or one slip, and the screw is down the abyss. Don't use anything but one of the flexible claw tools to start and remove these screws.

The abyss is also find of grabbing the camshaft thrust washer when you pull the sprocket off the cam. If you don't block the camshaft at the rear........it will slide backwards in a split second and the camshaft thrust washer (directly behind the camshaft sprocket) will fall into the abyss.

All these little tidbits are not in the FSM, however, and that's what makes the process a bit dangerous.

My strong advice is to GO SLOW and stop when you get tired or frustrated. Catastrophe is the next thing that will occur.

nhdoc, thanks for the write up, that is awesome. Where does one buy that $15 subscription, that sounds like monies well spent.

You'd be much better off spending a little more money and getting the FSM.

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-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

alldata.com...you buy a subscription for each car you own for one year. You can then access the same database that most techs use and follow - it is copied directly from the MB WIS/FSM anyway.

http://alldata.com/products/diy/index.html

I just checked and it is actually $25 for the initial subscription and $15 for each additional car...I have a couple of cars so I forgot they charge a little more for the first one.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

I don't know the 606 but since it is more recent I'll go off my unwanted intimate knowledge of the 603 head. There is no abyss. There is a separator on the timing cover that keeps the chain from ever falling in, unlike the dreaded possibility on the 617. I'm guessing that this is another nice to have that was added in the 603 along with the rear stop for the cam to keep it from walking during the installation. That said, when removing the cam gear keeping the chain from moving is a bit tricky. It will get to a point of looseness where cam no longer moves, but chain does. Mine moved a couple of degrees upon removal, but as long as you have marked the chain AND the gear in the same place, generally you just line up the two and timing will be maintained (including IP).

The key to removal on the 603 (and presumably the 606) is respecting to the letter the cam tower removal/retorquing sequence and the head bolt removal/retorquing sequence.

EDIT : There remains the timing case abyss which can suck in nuts and bolts. Be careful! I let one go down there and came to the conclusion that the magnet on a flexible rod is the BEST tool EVER (read : you do not want to take the timing cover off a 603 with the engine in the car)

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1982 300TD 210K miles ("The Replacement" aka "The Anvil") - SOLD
1979 300SD 245K miles (never ending project)
2007 Pinarello F3:13
1995 Ducati 916 (SOLD, sniff)
1999 Ducati 900SSie (SOLD)

I posted this on the other thread dealing with broken GPs...Speedracer stated he was able to get the threaded part out...so I responded:

"Speed, if the threaded part is out why not start it up and let the compression blow the rest out through the hole?

I bet it would shoot out like a bullet."

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

Maybe it would be better to just crank the engine by hand? Just to avoid any catastrophic possibilities.

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1982 300TD 210K miles ("The Replacement" aka "The Anvil") - SOLD
1979 300SD 245K miles (never ending project)
2007 Pinarello F3:13
1995 Ducati 916 (SOLD, sniff)
1999 Ducati 900SSie (SOLD)

Rodney Herson in N. Dallas did mine ~4 years ago. Of course, it wasn't exactly inexpensive...

- JimY

I'm having the exact same problem with one seized up GP (at the threads), and I'm pretty close to drilling out the threaded part. Once the threads collapse it looks easy to remove the rest of the plug, and none of mine were carboned-up so I'm not expecting my stuck plug to be.

Speedracer, is it correct that you have three stuck plugs? Have you removed the head yet? If you try starting the engine, will it run on only three cylinders? I know it can run on five...did it starting up this morning

Would turning the engine by hand generate enough compression in the affected cylinders to blow out the remnants...or would the air just blow past the plug? And I'm guessing the glowplug would shoot out like a bullet with the engine running...I'd put a piece of cardboard by the IP to protect all that stuff.....and myself

On second thought, I would strongly advise against using compression to blow the plug out......simply too much to go wrong..you could end up with a bottom end rebuild if a piece of GP found its way into the cylinder.

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99 E300 TD -- sold
01 540i 6 spd

My engine started up on only 2 glow plugs last year in sub-zero conditions.

Took about 10 seconds of cranking and grumbling, but she did it