i have just bought a set of mahle pistons & barrels and was told i dont have to take the pistons right out, just move them out enough to put the gudgeon through the conrod as the rings would already have the gaps in the correct position. does anyone know if this is correct?

homer,
That may be the case, but you don't know whether your ring end gaps are OK. It's a pain pulling them off pistons to check, but better 100% sure than seized up/scored bores later!


Ctefeh

You should take them out and clean them thoroughly anyway if they are new.
They have a protective coating on them that wont help the bedding in of them....
(presuming they are new)
You also need to set the ring gaps to where they should be too.

Every book I have ever read on assembling engines says that you should disassemble and clean new piston & barrel kits and reaasemble them yourself ensuring that the rings are properly aligned.

theres only one way to do it and thats to pull them apart and check the gap positions,

Also this allows you to lubricate the ring with oil to ensure they are ready to be run otherwise they will be dry on start up and this will create excessive wear on your new parts

thanks for all the replies guys. you have been a great help to a new vee dubber