This is my experience, what you find may be different, I'll update this page as I learn more about these engines. There are some Metros that were imported that do not have TRBs or Sleeves, Following are engines I've looked at and how they were equipped.
2/2004 Added Note:
If you plan to drive a generator head with a Lister clone, it is a good idea to pay attention to the mass of the flywheel. There are a number of clones with lighter and smaller flywheels. I can certainly understand why a designer would want to reduce this mass, but there are penalties, and you should understand them.
Listers are slow speed designs, you can get more power out of them by running them faster, but at some point you might ask why you've selected a slow speed design and choose to run it fast? A real Lister clone has a massive bore and stroke, there are no balance shafts and the faster you run one, the more vibration a ground pounding effect you have.
Look to the old Lister generator sets for guidance in your design efforts and selection of an engine. The heavier the flywheel, the more constant the speed of the output shaft. You can readily see the power strokes on a Lister clone with light flywheels by hooking an 'O' scope to the AC output of your generator. The power stroke can be seen as the cross over points of the sine wave move back and forth. The more flywheel you have, the better.
METRO Brand Engines
findings based on six inspections, and input from the field.
Update: Metro now builds a variant, I don't know how different it is from Standard, ask questions when you buy any Listeroid engine. If you have a tappet problem, see the tappet page for a fix, or order some standard tappets.
Prakash Brand Engines
Findings based on one tear down and two assessments performed by experienced owners.
Above: Prakash engine tear down, carbon on the piston top is from the test run and is typical . Notice the beautiful Metallic paint. Fuel filter on Left, cast iron top, pressed sheet metal cup. Note stock Indian studs, they are massive .715 thousands.
I was very impressed with the quality of this cylinder casting, it appears to use a higher technology than some of the previous brands I've tore down, if you shine a flash light down Through the coolant holes that align with the head, you'll see a very fine finish on the inside. You'll also enjoy seeing that this is a true 'WET' sleeved engine'. What this means is you don't have to worry about conductivity from the sleeve into the cast as you do a dry sleeve cylinder block, in this engine the sleeve itself is in direct contact with the coolant. The sleeve is sealed with two big 'O' rings of good quality. If you remove the fuel filter, you'll find letters BM in the casting.
Here's the head, note the standard Lister CS style Pre combustion chamber. carbon is typical of what I find in an engine that has been test run only. The head casting is also nicely made, they must use some pretty fine material on the inside to get this kind of finish. Note this goofy looking air intake (top), this engine is somewhat of a contradiction, it has really nice castings compared to most, but some of the exterior components are really low end parts, these are items I replace or discard anyway, so it's not that big of thing for me, but it might be for you.
It's simple to build a superior air cleaner setup, this unit was fabricated to bolt on an engine, and receive a standard round paper or foam element. If you have an air compressor, get one of those inexpensive die grinders and some three inch cut off blades, and you can make such an assembly in short order, having fancy equipment makes it go faster, but you can cut, grind, and weld some pretty nice looking stuff with basic tools and an arc welder. I thank Jim Wallace for the above example of his work..
Above: Now here's a vintage looking piece for you... a nice shiny yellow valve made of plastic. but look at that metallic paint! Bet that didn't pry your eyes off the fuel dripping off the line did it?
Above: Is the air inlet, standard bolt pattern and flange, you should plan to add your own filter, easy to do.
Above: Here's the standard MICO injector, never seen a bad one..
Shot of lower coolant inlet. I removed this lower coolant fitting and looked inside the cylinder, very well made casting.
Above: The flywheel, the finish on the wheels is pretty standard for Indian stuff... now worse, no better than usual, as they would tell you... this is a work engine, it wasn't assembled to show.
Above: A view of the massive Standard crank, you can see the TRBs fitted.
After two days of looking the Prakash over, I'd say it has all the important stuff... a true wet sleeve design that should work real hard and get rid of the heat. Some of the nicest castings I've seen on an Indian Lister, and the worst gas tank, pepper can muffler, I've seen from anywhere on the planet. This looks to be a great engine to build a show peace on, but remember, I've only taken apart one of them. be prepared to repaint it, and to clean paint off stuff you didn't want painted, and remember, we found one rod/crank pin fit that was not proper. If you're not willing to check a few things, buy one that has been gone through or get a guarantee that all is ready to go. Note what appears to be a forging mark on the crank.
After tearing down an engine this far, I thought I would pull the valves, check the valve faces, intake and exhaust ports. The guides and valves feel excellent, valve faces and seats are very nice. The intake and exhaust ports are the best I've seen, there's nothing to grind, sand or blend. It would be a total waste of time (IMHO). This head is truly the best casting I've seen, it would be nice to have two or three more Prakash engines to look at and see if the quality of these parts are consistent.
End of Prakash pictures.
I'll add more to this page as I learn the differences from one Brand to the next. Remember that the different brands make engines without sleeves, and without Tapered roller bearings, know what you are buying, ask questions.
I have quite a few spares at this time, if you bought a Metro engine, I encourage you to watch the rotation of your tappets, and address the problem if it does not rotate.