70 MPG Diesel Geo Metro

[Henry W]

Since gas is going out of sight here and I am already paying over $500.00 a month for it I am thinking of a Geo Metro conversion. If gas goes up to $6.00 a gallon I will not be able to afford driving what I have at this time.

A person contacted me and wrote the following below:

I had visions of driving over and see what you have. But its a long way from the San Francisco area. I'm 32 miles East in Pleasant Hill.

The adapter plate needs to be 1/2" thick. Mine was steel because that's all I had. It was reasonably flat and I did not do any special surface grinding. That will allow the transmission and cluch to sit precisely where it did with the gas engine. The throwout bearing rides in the exact same place using the 1/2" adapter plate.

I had a very slick way of getting all 6 dowel pins to match up perfectly with no measurements. Example... drill out all holes in the adapter to the engine. Even the 2 dowell pin holes, make them 7/16" (very oversize). Then tap the dowel pin holes in the adapter plate with threads, degrease, file faces flat, paint mold release compound on the engine dowel pins and their surrounding area. Bolt on the adapter plate on the engine and mix up paste epoxy steel compound and ram pack it in the dowel holes. After it cures, you can tap the adapter plate off with a hammer and it will come off nicely. The epoxy will stay in the adapter plate because of the threads you tapped. Not one measurement was made and it will fit any other Kubota engine.  I left the outside of the adapter plate uncut (picture #1) but marked it by clamping the transmission on and using spray paint to mark the dimensions.

The Kubota flywheel was not used. Way too heavy.  I mounted a 4 cylinder Geo/Suzuki Swift flywheel to the Kubota crank. The hub of the flywheel needs to be enlarged on a lathe a bit to fit the crankshaft stub. The bolt holes in the flywheel each had to be egg shaped with a die grinder to fit flywheel bolts. One of the Kubota crankshaft holes is offset so nobody can screw up putting the flywheel on with the timing marks in the correct location. The pressure plate and the clutch disk are also Suzuki Swift and are larger than the 3 cylinder Geo parts.

The pilot bearing fits the Suzuki/Geo flywheel bore. It is ball bearing. The only interference in the entire engine/transmission unit is that the Geo transmission input shaft is 1/8" too long. The transmission will sit 1/8" away from the adapter plate if something isn't done about it.  I chose to drill a 1/2" relief hole in the end of my Kubota crank in case I ever changed transmissions. I could have cut ff 1/8 " from the pilot shaft. The hole in the crank end was 3/16 deep which allowed plenty of clearance.

The Kubota starter uses the same tooth profile as the Geo starter. I flipped the Kubota starter over (upside down) and mounted it on the governor side of the engine right in the same hole as the Geo one did. I think I had to drill and tap new starter bolt holes into the engine adapter plate.  A new right angle thermostat housing must be built as the stock Kubota one will not clear the hood.  Since the engine tilts forward a bit, the oil pan hangs down right in the way of a rock in the road. A skid pan should be considered. I was going to modify the oil pan but the car is stored and awaits the day when I get bored of the diesel boat.

You need to consider that a diesel has no vacuum. You have to install some means to vacuum boost the brakes. I used the fuel pump to suck a reservoir into vacuum and piped that to the brakes. Not a good fix but better than nothing. Some extra pedel effort is required with the low vacuum available.

The stock in tank fuel pump seems to pump diesel fuel just fine. It has both feed and return lines and I teed into them to provide fuel to the injection pump. I actually adapted wire pigtails to the stock Geo wiring harness in case I put the gas engine back in. Nothing was cut.

The transmission has 2 mounting points. The engine uses the third mount. I made a bracket to fit the Kubota engine and support it near the original frame mount.  The Kubota engine is slightly longer than the 3 cylinder gas engine and the crankshaft pulley nut sits just below the right frame rail. This leaves no room for another belt (like for a vacuum pump).

Donor car: Mine was a 1990 Metro 3 cylinder convertible.  It looks like a hard top because I made the top myself. It is a removable hard top with sun roof and heated rear window.
The 89 to 94 were the lighter cars in all models.   You have the opportunity to get one with a 4 cylinder gas engine and 5 speed trans. That puts the engine more centered in the frame, gives you the proper bigger clutch and flywheel, and comes with beefier front springs.  Even the newer body style could be utilized as they were basically the same unibody with different sheetmetal, bumpers and lights until 1997 or so.  I do not think this engine has the guts to turn an automatic trans, or A/C.

The stock radiator worked fine. I added spin on diesel fuel filters under the hood and a manual switch for the glow plugs. The stock throttle cable also fit easilt to the injection pump. The start/run fuel shutoff solenoid was wired in to the key switch to make it shut off with the key. The other lever on the governor is a cable fuel shut off.

OK, driving this thing is for flat roads. It liked country roads between 35 and 55 mph and got 70mpg on my test runs. But it is clearly underpowered for the freeway as hills would just kill off any speed. The governor feel is a little strange. You rev it too much and the governor backs fuel off even if your foot is to the floor. I even drove it once foot to the floor around the block easily shifting into neutral and into another gear before letting the clutch out. That governor prevents overrevving.

I may put on a small turbo that I have some day. Right now there are too many things going on and I need to finish up the boat as the weather gets better. Then maybe the car will get some work. But California will not allow a diesel to be retrofitted at all. If I want to license this car for 2 years I will need to install the gas engine in it, smog test it, then cheat and put the diesel back in. Too much trouble right now and the license expired.  
Did you see the Youtube video?   http://www.youtube.com/watch?v=hnAOF1bOSB8

[Henry W]

The engine the person used on his setup is a Kubota D905 BG (1800 rpm setup for generators) His governor setup is not the best and is looking to change it. He has worked it a bit but it is still not right. He said it is easier to find a diesel that is set up for variable speed 3000 or 3600 rpm.

Henry

[WGB]

First let me say I love the project.
I'm thinking about doing something like that myself.
I was thinking an old CJ jeep with alcohol or diesel. Not really high mileage but I could make the fuel.
Also I quess I'm pretty much anti-govenment.
But what happens when you get stopped?
DOT, insurance, stationary/ag engine in car, fines? jail? just asking.
God help you if you get in to an accident, f'ing lawers would go ape!

[Henry W]

Emission and Safety Inspection Standard Exemptions for North Carolina

If your vehicle is at least 35 years old, it doesn't have to undergo safety or emission inspections.

If your vehicle's model year is previous to 1996, your vehicle doesn't have to undergo emission inspections.

However, unless your vehicle is also at least 35 years old, it will have to face the safety inspections.

[Henry W]

I am looking into it and will a find legal way to do a conversion. I know better than trying to hide something.
As long as I stay within North Carolina guidelines I will be fine. If I decide to do a conversion it will go through safety inspection and everything will be in the open that has been done.

I believe North Carolina lets you build a composite. As long as it passes inspection it can be registered.
I will be looking into that as well.

For now I will be getting another 1990-1993 240 Volvo. That will cut my fuel costs in half. I learned to get 32 MPG out of these bricks.

Then I can think about the possible Geo Metro Project or possibly a conversion with some other vehicle.

Henry

[BioHazard]

If I was going for a Geo I'd probably try and see what I could do with the stock engine and propane. Right now it's about the same price per BTU as taxed diesel. It's even cheaper if you get a few hundred gallons delivered.

Of course, a diesel engine running on propane would be even cooler, but, diesel engine conversions aren't cheap or easy...

Around here pretty much anything goes for transportation outside of two counties that have emissions inspections. Even there they don't check under the hood or do a "safety" inspection. I've never had an officier ask me what kind of engine I was running or even attempt to check if I might be using dyed diesel...

[Randybee1]

And my vote is.. a mid 80's diesel Jetta. I get 50.5 mpg with mine. There's no computer, I paid $1800 for it last April and haven't done a thing to it! I like the conversion idea too but..times a wastin'. It I were to build a conversion, it would take me many moons to complete. I think you'd be better off looking on Craig's list for a mid 80's small diesel!

Randy B

[Henry W]

I learned somthing about the Kubota engine the person used in the metro. The engine is externaly ballanced. So the engine is not ballanced with the Geo Metro Flywheel.

Henry

[T19]

I bought a VW Beetle, 2000 model for $2100 Cert on the road.  I get over 55 MPG, has AC and runs really strong.

With cars like that avail, why go through the hassle?

[BioHazard]

I bought a VW Beetle, 2000 model for $2100 Cert on the road.  I get over 55 MPG, has AC and runs really strong.

With cars like that avail, why go through the hassle?

I think the better question, is with cars like that available, why can't they produce a useable diesel powered plugin hybrid for under ten grand? I could build one in my shop out of junk for christ sake...

[cognos]

Tough to build a $10K hybrid with a $7K lithium battery... and that's why I believe electric cars and hybrids will be the transportation only for the rich who wish to make a statement for years to come.

A small modern car with a diesel engine is the future... all the problems sorted out by the manufacturer, safe to drive, reasonably clean, efficient, etc. - some of the older ones do quite well with-0 alternative fuels, and all the modern ones will burn biodiesel without modification - if you live in a warm climate...

Unless you want a hobby, that is. If that's the case, go for it!