quiz of the day: Why is this hole in my cylinder head?

[wayneh]

I was at the machine shop who is doing the work on my engine, and when I looked at the cylinder head there was a small hold that went all the way through to the outside of the head. On the outside the hole was tapped with what looked like a 1/8" NPT.

Am I the only one who doesn't know why that is there? The machinist knew!

The last pic is the pic of the block bored and honed.

Wayne

[Tom Petroff]

Nice!
The hole in #6 Cyl. is to insert a gauge (I use a rod) to check for max height
of the piston(TDC).
If #6 is TDC so is #1.
Hope this helps.
TGP

[wayneh]

Tom wins the prize.

Tom:

You win the prize! Not sure what the prize is, but that is exactly what the machinist said. Pretty clever of them frankly. I never heard of that before. I also learned our wheels are stamped with the date code. Happy for me all my wheels are stamped 56.

Wayne

[grover26]

Yes...Owning a PW is an ever learning experience.

[1946WDX#8900714]

I didn't know that

My 72' Triumph has a notch in the flywheel which helps indicate when you've reached TDC.

Tom can you explain the rod technique? Is it similar in that there is a notch that the rod would engauge to indicate TDC?

Kevin

[wayneh]

Kevin: put something in the hole until it touches the top of the piston. Turn engine over until it reaches maximum height. When piston 6 is at tdc so is 1. Talk about easy....


Wayne