Page 22 - KCRPCA JulyAug 2021

NUTS & BOLTS
M96 WATERCOOLED II
SOME SAY, THE “M” IS FOR MYSTERIOUS
Ileft off at the end of the last article with our 2.5L M96 Boxster engine ready for the piston install on the bank 2 side. Since at this point the two case halves are together, we can not just insert a piston and rod down through the cylinder and attach the rod cap at the other end like we did with bank 1, because the case is enclosed! So the Bank 2 side is a bit more tricky. When
I assembled the case halves, I already have the rods installed on the crankshaft. So now we need to connect the piston to the rod via the wrist pin, a bit backwards if you have ever rebuilt an engine before.
The idea is that we need to line up the piston and rod end, slide in the wrist pin that connects the two, and then insert a wrist pin clip into the piston to keep the wrist pin from sliding out. The
question is, how do we do that with an enclosed engine?
So here is a picture of our piston with a wrist pin in place for illustration. Then the wrist pin clip will install in the groove next to the wrist pin and keep it all together.
See Picture 1
We are going to insert the piston in the cylinder from the top like normal using a ring compressor as we did on bank 1. You can only do one cylinder at a time all the way to completion before moving to the next one (5, then 4)
The tools that are going to be used to accomplish this. One is a hollow tube, and the other is a solid insertion rod.
See Picture 2
Insert the wrist pin onto the insertion rod end as so.
TECHNICAL EDITOR KARL WILEN
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