Part Number 10-8901 10-8902 10-8903
K&B 3.5 Crankcase

Used on all K&B 3.5 engines

Check your crankcase before ordering
Here are the differences

The early 3.5 which used a small sleeve with an outside diameter of .750" This means the hole in the crankcase where the sleeve slides in is 3/4" diameter.
We do not have replacement crankcases for .750 diameter sleeves.

Later crankcases used a .765 diameter sleeve. This is .015" larger. This the the only case we sell.

10-8901 Used on all outboards and front intake engines.
Including early inboards and ducted fans.

10-8902 Used on ducted fan with drum valve intake.
Intake cutout is on the exhaust side.

10-8903 Used on inboard with drum valve.
Intake cutout is opposite the exhaust side.

Items usually purchased with this

29-8901 Gasket set
29-8911 Head Shim Set






Changes over the years

Sleeve bore changed from .750"Ø to .765"Ø

Added web to mounting lug.

Boss added behind screw holes
on exhaust flange.

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