Sleeve seems thin after machining to oversize

[littleape]

Hi guys, I have a '90 Evinrude 150 CrossFlow that needed oversize piston (0.064) and now after the machining I'm not too sure about how the sleeve looks. It's pretty thin on one side at about 1.2mm ..I don't want to assembly this and then have it break on me.

Is this bore trash or usable?

 

[racerone]

I have never machined one out that far.------I would find another block.-------But the large bore 175 / 235 hp were fairly thin too.

 

[littleape]

I have never machined one out that far.------I would find another block.-------But the large bore 175 / 235 hp were fairly thin too.

Did those larger models use the same block and simply had bores, with identical sleeves, machined to 3.625 vs 3.500 for the 150hp model?

New block isn't really an option, at worse I would do a re-sleeve of that one cylinder but even that would be pretty crappy if I have to do it.

 

[flyingscott]

Where did.you find a .064 piston? Never seen one go bigger than .040

 

[littleape]

Where did.you find a .064 piston? Never seen one go bigger than .040

Wiseco makes them.

 

[racerone]

Wiseco has been making them for many , many years.

 

[flyingscott]

Run it.

 

[Faztbullet]

Make sure you jet that cylinder a minimum of 2 sizes larger on main jet, and cooling system is 100%. Make sure you do proper break-in with several heat cycles to season piston.

 

[littleape]

Thanks guys

Yeah I picked up a 58C jet for that cylinder, I believe thats couple sizes up from stock.