Squish Test

I need the following before disassembly:
Please print out this page using the print button below, and send with your engine.

Compression Test                                                                                                                                          Ship to:
                                                                                                                                                               Lowell Horning
Ignition Switched Off                                                                                                                        2-Stroke-Porting
Drive Belt Off                                                                                                                           2565 Caribbean Drive
Throttle Taped / Wired Open                                                                                    Lake Havasu City, AZ 86406
Same Number of Pulls Each Cylinder --- # of Pulls ________                                    Tel: # (928) 855-6677


Watercraft: Wide Open Throttle, Plugs Out & Wires grounded.


Note if engine Warm? or Cold?

MAG __________ psi                               CEN __________ psi                                    PTO __________ psi

Squish Test

Cut soft lead solder square on the end with a utility knife and bend into an "L" shape. Put the solder thru the spark plug hole, align with the centerline of the crankshaft, and push end tight against cylinder wall over the wrist pin in the piston. Turn the engine over very slowly with the clutch, or flywheel, as you reach TDC. Watercraft: use the starter to bump the engine over Slowly. Remove, cut off flattened area, record thickness with a vernier, and repeat on the other side of piston. Mark PTO & MAG for each cylinder and M & P for each side of cylinder. Masking tape will hold your pieces in order for future reference. Solder cut square and put tight against the cylinder wall usually squishes down beside the piston - proof you got and accurate measurement of piston to head clearance.

Once you have completed the above procedure, tape the flattened pieces to the proper locations on this test form printout, and enclose the form with your engine.

PTO Cylinder P = ________ M = ________ Inch or MM?

CEN Cylinder P = ________ M = ________ Inch or MM?

MAG Cylinder P = ________ M = ________ Inch or MM?

I will need the centre to centre length of the Connecting Rod. __________ mm

Record Head & Base Gaskets -- Rotax: # Holes in Base Gasket = 0.1mm thickness.
Yamaha: Base & Head Gaskets # of layers in each = 1-3.