OK, copy of letter to Jack....
Date: Mon, 4 Apr 2011 10:55:54 -0700
Hi Jack... been a long time. Hows the Escape from Berserkeley car doing? My diesel Metro sits idle unable to be registered in Calif due to the state hatred of any diesel.
I worked in the Middle East, South America, and Taiwan as an engineer for General Electric Co. installing gas turbine generator sets and overhauling them. The special fixtures, jigs, tools were always missing so I had to be very creative to get the job done. I love to do the impossible and prove the naysayers wrong.
My engine adapter was a square steel 1/2" plate bolted to the Kubota while getting rid of the SAE bellhousing. The 4 cylinder Geo flywheel was installed with the alignment diameter cut to provide a .001" interference fit, bolt holes egg shaped to fit the Kubota crank pattern. A new pilot bearing was installed. I put the Geo transmission in (and discovered that the pilot shaft was bottoming out on the crank 1/8" interference). After drilling a relief in the crank end I rotated the trans so the bolts cleared the cylinder head and clamped the trans with c-clamps after removing the trans hollow alignment dowels.. After everything fit well I spray painted the transmission housing and adapter plate with silver paint making sure to hit the transmission bolt holes as well. That's the poor man's way to get a decent layout.
Remove the trans and adapter plate, center punch the holes and center punch the entire outline of the adapter plate to torch cut the excess metal off. After deburring everything on the adapter plate and drilling all of the transmission bolt holes I made 2 new transmission dowell pins out of steel about 1-1/2" long and put a nice pilot hole in one end. I drilled the transmission locating dowell holes 1/8" oversize in the adapter plate.
For grins I upended the Kubota engine such that the adapter plate was flat horizontal. Then I put the trans on it along with a dial indicator and moved the trans around to find its natural concentric center and clamped it together with temporary transmission bolts and nuts. I think it could have been done without a dial indicator as the pilot bearing, shaft, and input bearings felt rigid enough to get a good alignment before tightening.
Turning the engine/trans horizontal again, I tapped the new dowels into the holes of the transmission housing with the pilot holes towards the trans. I welded the dowells to the engine side of the adapter plate using awet rag to cool things off quickly. Viola, precision fit transmission dowells. Then take it apart again and cut off the excessive dowells where they were welded, and drill out the dowells on a drill press to fit the last 2 transmission bolts that pass thru the center of the dowells. I sanded off about 1/16" from the dowells in case the next transmission dowell holes might be machined shallower. Now any Geo trans fits your adapter plate once you drive out the stock hollow alignment dowells.
I also fit the Kubota starter near the Geo location on the firewall side of the engine. It needed to be inverted and the drain hole plugged with silicone. The Kubota teeth mesh perfectly with the Geo flywheel teeth as they are the same profile. I filled the engine with oil and started it several times to make sure the starter was in the 'quietest' location and the drive would retract properly. I dowelled the starter holes as well. Here's a vid taken somewhere along the way....Kim