MWSC FAQs: Fuel / Exhaust, Ignition, Timing, Boring, and Cooling

Fuel / Exhaust

Can you use gas or alcohol in the plastic fuel tank?
Yes, either fuel is suitable.

Is the fuel pump you offer gas or alcohol?
Either, the pump we sell is suitable for both.

What size pipe goes with the XF12 (Exhaust Flange for a 12 HP)?
The 1-⅜” ID (inside diameter) pipe. Part # 51610 for Plain

What size pipe goes on the XF16 (Exhaust Flange for a 16 HP)?
The 1-⅝” ID (inside diameter) pipe. Part # 51609 for Plain

Ignition

What else do I need to make the Electronic Ignition (EI) work on my tractor?
You need a 3 OHM coil. We sell a Voodoo Coil (Made in the USA), or you can use the Blue Bosch Coil.

Timing

How does “setting my timing” change the motor?
For a 1 Cylinder K-Series Kohler, change the point gap. More gap = more advance timing

Boring

How big can you bore a stock block?
Note: Measure cylinder wall by placing calipers between fins and ID (inside diameter) of cylinder.
For the 10 and 12 HP blocks, biggest you can bore is 50 over on older style which is 3.420. Largest valves for the 10 HP = Intake 1.850 and Exhaust 1.500
The newer style blocks can go 3.530 for 14 HP
16 HP stock blocks can be bored 30 over 3.780 to 3.937, head strap is needed!
18 HP stock blocks (K361) can be bored to 3-15/16”, must have head support!

Cooling

What size is the cooling fan?
About the size of a pop can.

Where should the cooling fan be mounted?
It should be mounted on a solid surface, and be pointed at the head and cylinder wall. Vibration will cause the fan to fail or fall apart, to help avoid this use rubber grommets to mount the fan.