Geo Metro convertible / Kubota diesel engine conversion (driving!)

[kimer6]

Sounds good. My Kubota had a very road unfriendly governor and no variable injection timing like automotive types have. It was made to run a certain speed and if you varied from that speed it would either open wide open and smoke or cur fuel alltogether. Kubota has a proper governor but I am unwilling to pay $2000 for it when the whole car, engine, parts, etc total to about $800. So if you stick with any kind of car diesel it already has a good fuel governor from the factory.

[highmileagemarshmallow]

found a '82 rusted rabbit with tons of extra parts and a handle full of injection pumps for kinda cheap. the 1.6 diesel and five speed should be tight in my Marshmallow so i'll have fun with some torch work. i really cant wait see my festiva sippin on all this SVO ive been collecting!

[highmileagemarshmallow]

but my next job will be to actually finish my wood gasifier and get it flowing. but if that VW works awesome in my daily driver festiva, the wood gas is a must for my '89 festiva. cant wait for eigther!

[kimer6]

Please post some pics of your project. It would be nice to see you make it happen...

[doejohn]

Sure enjoying reading about the Geo Metro with the Kubota diesel engine. I have a lot to learn. Am trying to expand my bolt-in engine swap skills (i.e. swapping gas oldsmobile for diesel) to encompass this.

Using Paul Dempsey's "How to Convert ... to Diesel" book to try to grasp the details in making the bellhousing to engine adapter plate.

Maybe someone would care to answer a beginner question? How do you accurately mark and drill a hole in the adapter plate?

Thanks for the information in this thread.

-Ed

[JackMcCornack]

The critical measurements are the dowel pin locations and the crankshaft center...and they aren't nearest-thousandth critical 'cause there's some flex in the transmission input shaft. Once you have the engine and bell housing dowel pin locations in the right spots (and put dowels in them), you can use existing holes as your guides. For the through holes, mark 'em though the holes--use transfer punches if you've got a set (or if HF is running a special). For the threaded holes, I've used grub screws with an internal hex (Allan head) and cut off short pieces of the appropriate allan wrench, sharpen them on one end, and put the other end in the grub screws. Then put the adapter in place (located with the dowel pins) and tap it with a soft hammer; the pointy things you put in the grub screws will mark your mounting holes.

Also there are places that measure this sort of thing for a living. Call a local high end machine shop and ask if they have the equipment in house, or if they can recommend anyone who can do it for you. If you bring in two <very clean> bell housings (one to fit the engine and one to fit the transmission) and a hundred bucks you should get all the info you need.

[kimer6]

Here's what I did... make a cardboard template with poster board and use a small ball peen hammer to gently tap around the bolt holes in the engine block and the dowells. Leave the cardboard larger than the transmission bell housing. Drill all bolt holes that you will use in the adapter, make them a loose fit. Drill the dowell pin holes out to 1/2" dia in the adapter plate. Tap the dowell holes in the plate with 1/2-13 threads. You don't care where the adapter plate sits on the engine. The trans will be the precision fit. Deburr all holes, run a file on the adapter plate to see high spots. Dissolve some wax in thinner and paint the dowells and the block around them. Bolt up the plate good and hard, mix up some steel epoxy paste and ram pack it in the adapter plate and around the dowells. This will keep your adapter in line always. If you gently tap the adapter plate off, the threads you put in will keep the epoxy dowell pin holes from moving or falling out. When you line up the transmission you can do the same thing with the transmission dowells.

Geo trans to Kubota diesel...needs 1/2" thick adapter plate and then the clutch will line up in the stock location. The flywheel holes need to be hand fit, egg shaped. The flywheel register fiy needs to be slightly counterbored to fit the larger Kubota crank.You MAY need to trim 1/8" off the input shaft of the transmission pilot or grind a relief in the end of the Kubota crank...

There is too much to tell here but you or anyone else can email me at CBX_KIMatHotmail.com ....change the at to @.... I like innovative creative problem solving and many times have to forgo precision layouts and fancy measurements. If the 2 shafts are concentric the trans and crank don't care how they got there....Kim

[JackMcCornack]

Clever!

Originally Posted by kimer6

There is too much to tell here...

Heck no, inquiring minds want to know. Please tell it all--I've sent you an e-mail as you suggested but I suspect many other ecomodders are panting for details. Now that you've solved how to get the dowel pins in place on the engine side, I want to hear how you lined up the transmission with the engine.

[kimer6]

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

http://www.youtube.com/watch?v=3W2PyKG2MfY

[cRiPpLe_rOoStEr]

That's an awesome project. I'm a die-hard Diesel enthusiast, and I like the ways you were overcoming the limited availability of light-duty Diesels back there.