Originally Posted by
wrench1
These clips are standard and cost about $0.70 USD each. Nothing special about them. The ring grooves and retainer plates are checked as part of overhaul with the bushings changed as well. Usually one buys a ring kit for OH and gets new circlips for this application.
Probably, though the mechanic might have applied "general" knowledge (nothing special) and now, we do have panic, including ac/incidents, around these engines, focusing on the circlips.
Originally Posted by
ShyTorque
I’ve been rebuilding engines (mainly air cooled motorcycle types) since the early 1970s and have always been aware that the side of a circlip with the sharp edge should be the thrust bearing side. They don’t come with instructions! A good example is those holding gudgeon (wrist) pins in pistons. The last thing you need is a loose clip and the end of the pin scraping the bore. The rounded edge of the circlip can ride up the (square edged) groove and pop out the same way it was incorrectly put in. Wire circlips are different in that they have rounded grooves.
For this engine, it got explicitly specified. Probably not to nag the mechanics, but because of genuine reasons, which could be the reasons you specify or maybe additional ones. I've seen so many detailed instructions, thinking "why the hell do like that", though sometimes finding out later, there were genuine reasons to do so. So, for me, manufacturer instructions are the leading instructions.