5 replies to this topic

[beentheunseen]

Hey everybody, was just cleaning my pistons ready for re-assembly of my 1989 998cc A+ engine and spotted this on no. 4:

 DSC04649.JPG   1.08MB   45 downloads

...and on the other side of the piston:
 DSC04650.JPG   1.25MB   28 downloads

What could be the cause of this? I'm guessing it's lack of oil to the bore, but the engine has never seized to my knowledge... The bore itself seems totally fine, and I measured the piston-to-bore clearance and it's well within tolerance. I was wondering if this could could indicate piston slap, which could be the cause of my strange rattling noise (video here: ) but as the clearance is ok and the sound never improved as the engine warmed up maybe not...

Can anyone advise me on this?

Edited by beentheunseen, 26 January 2010 - 04:21 PM.

[Guess-Works.com]

take the middle ring off the piston and check that down the bore... that seems to have one hell of a gap

[beentheunseen]

take the middle ring off the piston and check that down the bore... that seems to have one hell of a gap

Oh yeah, I checked all the rings down the bores, they all seem ok, I think it's just an illusion of the photo.

[bmcecosse]

Are all the rings free to turn in the grooves - and still 'springy' ? It certainly HAS been partially seized - it may be ok if you clean off all the damage - but another piston would be the best idea........

[beentheunseen]

Yeah, the rings are totally free and springy... I'll be on the look-out for a new piston (if anyone in the Nottingham area has a suitable 998cc flat-top A+ piston or set of pistons, give me a holler)

[HARBER07]

Are they standard size pistons? If so i may have one (well 3)