mixed piston sizes

[smoodz]

Hi all hope someone can shed some light on this.
I have stripped down my 4e-fte engine to find the piston in cylinder three melted on the inlet side towards the cam belt end the problem is that although the bore is not damaged as far as I can tell, on closer examination of the pistons they are not a match. Two of them are numbered 2 and two of them are numbered three.
As I understand it that would mean that the size three are over sized by 0.0010 is this something that can be done in certain circumstances to overcome a problem or has it been bodged .
I have only had the car six months but have been driving it ok with this set up until the meltdown.

Any Ideas plz.

Cheers Sam

 

[5e colin]

check ur block its says on the block at 12 oclock of each cylinder what nr piston gose in the bore

 

[aidan]

Mine was the same when I opened it up not sure exactly what cylinder but one was a size 3 and my engine was never opened

 

[Mikey4410]

Thats odd.i thought pistons shud really be the same....

 

[5e colin]

Thats odd.i thought pistons shud really be the same....

yes the nr on the block should match the nr on pistons to stay in tolerance

 

[weeJohn]

When re boring to a bigger piston, a machine shop will bore to the size of the piston, determined by measuring each piston in turn. In the factory they don't have that time so they match the bore to a piston.

 

[Tim@TBDevelopments]

toyota had a few different size pistons in standard 74mm size. this was to correct for mass production engine boring which was never ideal. instead of spending more time getting the bores perfect they just gave the block a tolerance than then corrected the expansion gaps with slightly different sized pistons. They did the same with the mains and big end bearings.