1919 9 HP Type E Economy DIY rebore

A do-it-yourself cylinder rebore


| June 2009



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The drive shaft that Howard Kittleson created to rebore the cylinder on his 1919 9 HP Type E Economy. Howard fabricated the tooling for the project, and used his 1942 16-inch-by-102-inch Monarch lathe to make the cut.

This story started in 1995 when a gentleman from the Dalton, Minn., threshing show had some engines for sale.

Among these engines was a 1919 9 HP Type E Economy. The engine was mostly complete, but was missing the ingiter and magneto, and the igniter port was open. It was also stuck, with the piston all the way back. Had the mice and moisture had their way with the cylinder bore? I had no idea.

Taking a chance
I wanted the engine but did not buy it. I looked at it again a year later but still, no deal. In mid-winter 1997, I finally purchased the engine on a handshake as the owner wanted no money until I picked it up in the spring. Several weeks later, the owner’s obituary was in the local newspaper. I thought for sure the Economy deal was broken, but I contacted the family at a later time and they assured me they knew about the agreement and that the engine was still available. More good engine people.

Worst fears realized
When the weather allowed, I picked up the engine and started the restoration. It took a week to get the head off, and my fears were correct – there was a huge mouse nest and lots of nasty pits in the bottom of the cylinder bore. I cleaned and polished the bore and filled the bits with a two-part epoxy (LPS Tough Titanium), honed the cylinder, re-grooved the piston ring grooves, installed a set of Joe Sikes custom rings, as well as new valves, gaskets, igniter and magneto. It ran, but it also splattered a lot of black oil all over the back of the engine. I ran it that way for several days but it lost compression and eventually wouldn’t start.

I had to fix the bore, but with limited funds for the project, I had to look at lots of options. I have a machinist’s background and for years worked in the heavy equipment maintenance field. A common job back then was to repair worn bores on heavy road and mining equipment with portable line boring equipment. We would bore the worn area and press a sleeve in, or weld the bore and machine it back to size. I decided to use this method to oversize the bore and then make an oversize piston. This engine has a 6-1/2-inch bore and a cylinder almost 2 feet long, and most engine rebuilding shops could not machine a bore that long.

DIY engine rebore
I had to fabricate most of the tooling to machine the bore. The tooling included two self-aligning 1-15/16-inch ball bearings; a boring bar of 1-15/16-inch cold-roll steel shaft; two universal joints; a length of 1-1/18-inch hex shafting and a 1-1/18-inch sprocket hub for the hex shaft to slide through; another self-aligning bearing on the end of the hex shaft; a machined boring tool holder; a 1/2-inch brazed carbide boring tool; two centering rings; miscellaneous steel; and spacers, adapter plate, nuts, bolts, etc.