Polish jet pilot
4aces4aces4aces4aces4aces
- Location
- Warsaw, Poland
Hi all,
I got from a customer, an ex-Ross Champion ski (orange and white, JSU graphics on front) with about 760cc. It is a bibore ported 61x cyl on 62t worked cases and bolt on goodies, It uses 65U pistons. It was brought to US to Poland some years ago, was somehow "adjusted" to work on lower lever octane fuel (someone added an oem head gasket to the girdled ada head with orings, and doubled the base gasket for the cylinder).
The motor lost compression, so I took it apart and found few things such as: hone is almost gone, some scuffs on cylinders, sleeves which move inside the cylinder casting up to about 1 mm horizontally...and this is my biggest issue. How would you go about it - take out the sleeves and put them again? Replace and try to port them again (i'd prefer not too, but it might be needed). There was an idea from one of the guys at the machine shop to insert bolts into the cylinder casting so they would strenghten the casting around the sleeve..
The cases extremely nicely done part - fully epoxied. ported and polished, crank is strong - no problems.
Need to calculate correct compression so it can run on eg. 98-100 octane (Euro), and have good low end snap.
If you may have any suggestions or knowledge about this motor please help out, it's a nice ski but its thrashed I want to make it nice and rideable again
thx!
I got from a customer, an ex-Ross Champion ski (orange and white, JSU graphics on front) with about 760cc. It is a bibore ported 61x cyl on 62t worked cases and bolt on goodies, It uses 65U pistons. It was brought to US to Poland some years ago, was somehow "adjusted" to work on lower lever octane fuel (someone added an oem head gasket to the girdled ada head with orings, and doubled the base gasket for the cylinder).
The motor lost compression, so I took it apart and found few things such as: hone is almost gone, some scuffs on cylinders, sleeves which move inside the cylinder casting up to about 1 mm horizontally...and this is my biggest issue. How would you go about it - take out the sleeves and put them again? Replace and try to port them again (i'd prefer not too, but it might be needed). There was an idea from one of the guys at the machine shop to insert bolts into the cylinder casting so they would strenghten the casting around the sleeve..
The cases extremely nicely done part - fully epoxied. ported and polished, crank is strong - no problems.
Need to calculate correct compression so it can run on eg. 98-100 octane (Euro), and have good low end snap.
If you may have any suggestions or knowledge about this motor please help out, it's a nice ski but its thrashed I want to make it nice and rideable again
thx!
