Author Topic: Strange timing chain guide (Read 4063 times)

pierre02ti · « **on:** December 23, 2012, 03:41:05 PM »

Rebuilding a defective M42 1991 engine with parts from an engine purchased with no history.

The timing chain long guide on right hand side from the spare engine looks much better than the original but is very different: all black plastic while the original is metal with plastic inserts.

I guessed it was an upgrade as all dimensions fits correctly.

# in the rail of the "new" one is 11311727697 if I am right.

After the installation, I search to conform what I have but cannot find any reference in Realoem or Google.

What do I have? Picture attached

Pierre

pierre02ti · « **Reply #1 on:** December 23, 2012, 04:19:28 PM »

Found a picture that shows this new design.

Pierre

colin86325 · « **Reply #2 on:** December 24, 2012, 08:11:34 PM »

The M42 timing chain guide has been supeceded to the the M44 design shown in the picture. You need to use a different mounting bolt (or two??) with the new design. You have to set the mounting depth with the new bolt so that the chain passes through the center of the guide.

bmwman91 · « **Reply #3 on:** December 24, 2012, 09:47:05 PM »

Make SURE that the top bolt in the guide is 45mm long. The updated plastic guide is a newer, improved version, and the adjustment sleeve is 5mm longer. The old 40mm bolt will just strip out and wear its way through your aluminum timing cover!