OM617 tensioning rail snapped / Timing chain position

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OM617 tensioning rail snapped / Timing chain position

Post by Dweezil » Wed 27 Jun, 2018 12:26 pm

Hi Team,

today's trick question...

After changing the timing chain, I've noticed that Jurgen's tensioning rail has snapped at around the '85' line in this image:
Is there an unmarked guide pin that goes through the bottom of it as indicated by this image:
and if so, how does one get at it and replace it? And yes, for the record, I have a new tensioner.

Moreover, there's every chance that I've skipped one or indeed several links in the process of getting the new chain on. If I've got the first cylinder at Top Dead Centre and the cam sprocket at Top Dead Centre and the first cam lobe pointing horizontally to the LHS of the engine bay, how can I test that it's doing what it should be doing?

Grace period after rego expiry is rapidly running out, so all help gratefully received.


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Tony From West Oz
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Region: Victoria
Location: Bedfordale WA

Re: OM617 tensioning rail snapped / Timing chain position

Post by Tony From West Oz » Wed 27 Jun, 2018 5:23 pm

Yes, there is a pin at that hole in the tensioner rail. It is the pivot for the rail.
Check that the timing mark on the crank and the IP drive (remove vacuum pump) are aligned when the cam is at the timing mark.

How to tell that the crank and cam are timed correctly? Rotate the engine using a socket on the crankshaft bolt and ensure that the crank goes a full 2 revolutions without valves hitting pistons. The marks should still align after the 2 rotations of the crank.
Others may have a better method. I am happy to learn.
Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

'83 W123 300D 325000km (Wife's car Josephine - sold).
'84 W123 300D replaced good OM617 912 with OM617 952 and enjoyed having good acceleration for the first time since first driving a 300D in 2002 - became engine and trans donor for 300CD Turbodiesel conversion. Now parted out.
'86 W124 300D sold (Wife's old car - sold )
'85 W123 300CD, 275 000km (Fatmobile) rebuilt turbodiesel transplanted into 280CE (SOLD)
'99 W202 C250 Turbodiesel (my darling Wife's car - Sold)
'98 W202 C250 Turbodiesel (my car - Sold)
'06 Ssanyong Musso Crew Cab 2WD Ute (OM662 diesel and Auto Transmission)
'00 Ford Courier Crew Cab 2.5TD

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