Trouble fitting new piston rings in my 1964 V90

[stevew]

The engine is totally standard, and has never been rebored. Have just got 2 new 47mm rings and gapped then to 0.25mm.

I can just start the first ring in the barrel but it seems to jam and the piston is stuck solid, the rings are fitted correctly around the locating pegs.

Piston is the original standard size and the grooves are clear of crud.

if i measure the thickness of the old ring ie inside diameter to outside diameter they are 1.5mm, new rings are 2.0mm.

Have I been sent the wrong rings or are the old ones very worn?

Thanks.

[tzsteve]

Sounds like the wrong rings

[jbcollier]

Measure the depth of the ring groove in the piston. I think you'll find that it's less than 2mm.

[stevew]

The groove is definitely less than 2mm, with the ring in the groove it sticks out very slightly passed the piston when you squeeze the ring.

[jbcollier]

Wrong rings then. You need 1.5mm rings as original.