Wrist/piston/Gudgeon pin Circlips

[keynsham1]

I was always advised not to reuse the circlips that hold the piston pin in place as they can fail. I did have this happen on a motorcycle and you can imagine the damage. Nowhere in any book, however, does it comment on the circlips as parts to keep, replace or anything. They seem to be absent from most UK parts suppliers stock lists even though pistons and barrels are readily available. Does anyone have an opinion?

[hightuned]

Measure the groove for the circlip in the piston, im sure you can find a set in the correct dimension from other pistons with the same size pins as std component like a circlip is more the likely reused on lots of different pistons.

[KTL]

Factory manuals say not to reuse them. They're less than a dollar a piece. I just bought 12 of them ($0.42 each) for a set of used low mileage Carrera pistons I have that I plan to sell. $5 is very cheap insurance.

Here's teh 993 manual for reference

[keynsham1]

Thanks for that. I was planning to replace them anyway. Interesting however that no other engine rebuild books seem to mention this!

[Eagledriver]

This is the first time I've heard of this. I'm sure it's a good idea to replace them, however, they don't seem to wear out and I've never seen one break.

-Andy

[brighton911]

For sure, do replace them. They certainly don't wear out but the act of removing them can deform their shape and possibly mean a less than perfect fit in the groove (if re-used). I can tell you from my motorcycle rebuilding days, a popped out circlip does awful mean things to a cylinder wall.

[Steve@Rennsport]

Originally Posted by Eagledriver

This is the first time I've heard of this. I'm sure it's a good idea to replace them, however, they don't seem to wear out and I've never seen one break.

-Andy

I've seen several broken ones so its always good practice to replace them.