Peter Rooke finishes a tough IHC restoration project – Part 3 of 3

| April 2008


The new pushrod alongside the old one.

Editor's note: In the December/January issue, we began a three-part feature on Peter Rooke's latest restoration project. We conclude below with Part 3.

Pushrods and trips

All pushrods and trips had either been sawn through during disassembly or were in need of replacement; easy threading exercises.

The replacement hardened steel roller for the cam follower and its pivot were made out of drill rod. When drilled and turned to the correct dimensions the roller was hardened by heating to cherry red then quenched in brine. It was then tempered by heating to 340 to 390 degrees Fahrenheit (a yellowish color) and then held at this temperature for 10 minutes before being allowed to cool slowly.

The exhaust pushrod and ignitor trip required simple turning and fabrication tasks to copy the originals.

The follower arm for the eccentric strap was cleaned, and the rod and locking bolt threads were cleaned with a tap. A new retaining plate, screws and gib key were needed as they were missing or damaged.


There are several components to the governor in addition to the rod and butterfly beneath the mixer.