Case/Cyl Swap Early vs Late H2

Oil is fed to the cylinders via oil lines to carbs w/check valves on H2B/C motors. This system uses a four outlet pump and a one to three case oil line.
- Cases are not drilled for oil feed to cylinders as are early cases
- Cylinders are not fitted with oil restrictor jets as are early cylinders

To use H2B/C cylinders on H2/A cases oil jets must be fitted to cylinders.  (3 outlet pump, 3 separate oil lines)
To fit late cylinders on early cases you can tap the oil hole to 5 X.08, cut the end off of a #30 pilot jet, and install only the threaded portion of the jet in the hole. Don't drill all the way through when getting the hole ready to tap, so there is no way the jet can end up stuck to your piston. And use high strength loctite. The #30 pilot jet is about the same size hole as the pressed in jet in the early cylinders.

To use H2B/C cases on H2/A cylinders oil feeds (3) must be drilled into to case.  (3 outlet pump, 3 separate oil lines)
Be careful to drill above where bolt threads will be.

To use H2/A cases on H2B/C system case needs to have oil feed to cylinders blocked off.  (4 outlet pump, 1 into 3 case feed line, 3 lines to carbs w/check valves)