Injection Timer, Front-Bearing 61x engines....

[Alastair]

Definitely worth checking, if you have your engine in bits. This phosphor-bronze bush bearing sits behind the automatic injection timer, (the IP drive-sprocket behind the vac. pump)....

While re-building my 617, I assembled the short IP drive and skew-gear for oil-pump drive (N/A only) into the block, and checked the side-shake of this bearing.--Huge!

BUT the excess clearance was Not the bearing bush where it runs on the shaft, The bearing bush was loose in the block. Its held in place by a 10mm bolt with a large washer that sits in a groove in the bearing.

On removing the bearing, it can be seen that it has worn a nice groove, through preumably vibration to make it a loose fit in the block. A replacement bearing bush fixed the issue, and is a tight fit....

--Just thought I would let you guys know. This part is often overlooked in a re-build, as the bush bearing surface does not wear much in normal operation....