How bad is too bad? I'm about to pull the front end apart so I can pull the crank down to do the rear main seal (someone talk me out of this!). Following the thread on the rear main it looks like the chain has to come off so the crank can get pulled far enough to clear the rear seal.

Anyhow - if I have the chain off, how do I check it? With American chains I hold them sideways and if they droop more than a little (say, 1 1/2 inches max) it's time for a new one. Is there a similar test for the M-B chain?

Dan

The test is done with the chain installed based upon camshaft timing. If the timing is late, a Woodruff key is utilized to return it to spec. There is no requirement to replace the chain on a 617 unless it was horribly neglected.

Thanks. I wish I knew how neglected this poor ol' gal is! I'm guessing my Haynes manual will show how to check it.

I just reread the rear main seal thread and maybe the chain can stay there. Sounds like they just removed the tensioner bolt and a chain slide (I guess that's accessible with the cam cover off) and that gives enough room to pick up the crank sufficiently. It would be easier to leave the front cover on.

Dan

.............front cover?? What's a front cover on a 617?

'Zakly! I was looking thru my Haynes and sure enough the chain fits in a cavity in the block casting. Never seen that one before! Live and learn.

IH DT446, Cummins ISB, and all the other Diesels I've been into all had front covers. Learn something new every day.

Dan

When you get yourself a six cylinder, you get a front cover. Much more complicated and sophisticated engine. Of course, the front cover can explode on occasion................

Consensus has it that you cannot drop the upper Oil Pan with the Engine in the Vehicle to change the Rear Main Seal.
I have also read that there is some sort of Pin that sticks into the Rope Seal that keeps you from just yanking the Seal out as you could on My old 1953 Chevy.

__________________
84 300D, 82 Volvo 244Gl Diesel

Yup, your Consensus is correct.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Hey Brian at what point do you have to install a new chain? Is it an easy fix to replace woodruff key instead of chain?

I don't think there is a defined point at which you MUST install the chain. However, the sprocket wear is greatly increased when the pitch of the chain differs from the pitch of the sprockets.

I would take an educated guess and suggest that 8 degrees should be the absolute maximum that should be accepted when measuring the elongation via the dial indicator method.

The Woodruff key is a fifteen minute fix, provided you don't drop the key down the abyss...........then it becomes a nightmare.

The chain is more difficult and has quite a bit of risk associated with it unless you understand and follow the correct procedure.

He is talking about this thread:
http://www.peachparts.com/shopforum/diesel-discussion/298852-rear-crankshaft-rope-seal-replacement-without-removing-crank.html

__________________

All Diesel Fleet
1985 R107 300SLD TURBODIESEL
2005 E320 CDI (daily)

LOTS of parts for sale!


EGR block kit
http://www.peachparts.com/shopforum/diesel-discussion/355250-sale-egr-delete-block-off-plate-kit.html

1985 CA emissions 617 owners- You Need This!
Sanden style A/C Compressor Mounting Kit for your 616/ 617 For Sale + Install Inst.

Sanden Instalation Guide (post 11):
http://www.peachparts.com/shopforum/diesel-discussion/367883-sanden-retrofit-installation-guide.html

I believe you also have to re-time the injector pump, correct?

__________________
1981 Mercedes 300TD, 1994 Honda Civic Del Sol
http://mefi.us/images/fuelly/smallsig-us/67195.pnghttp://mefi.us/images/fuelly/smallsig-us/103885.png

My engine is out - and sometimes in - then out again - and so on as I fit the bugger into the S-10. I'll pull the trans and have it resealed then mount the engine on one of my stands and do the front and rear main seals. It's leaking like the proverbial stuck pig.

I was just thinking that if I had to disengage the timing chain to lower the crank I might as well renew it but that evidently is not the deal.

Dan

If you do end up lowering the timing chain into the block, it's really really easy to get everything timed when you put it back together on a stand-you can see all timing marks clearly.

I'd check the timing via the indicator method before pulling it apart any further. Also, while you have it apart you might want to consider this (if you have deep pockets)

http://www.mercedesdiesel4x4.com/product_p/a-mb102.htm

A low profile welded upper oil pan. I know you already scalloped your pan, but this is just another option

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

I get special designer work pants with shallow pockets. Hence the scalloped pan! Seriously, I'm doing this on a part of my Social Security check - a little bit every month.

Dan