Hello all, this is going to be a somewhat simple instructables. So here is some background information on the build, it started when a few years back we had a Polaris 350 Trailboss, and the engine finally gave out after many years of enjoyment and after that we just let it sit unitl we finally remembered we had an old Honda 240cc cement mixer engine with a gear reduction already on it, so it sounded like the perfect fit for it. So without going much more into the background here is the build.
Just to be clear I and the people involved in this took extra care while handling the propane, and we are not responsible for any damage caused to yourself or any property that you, (or your neighbors) may own. So please only attempt this if you know what your doing, and have sufficient common sense to know what you should and shouldn't do.
Also I am very sorry for the video quality thats all I could upload on to Instructables.
Here is a link to the youtube video it is of much better quality. http://www.youtube.com/watch?v=RneAye-NetM
Here also is an older video of it with details. http://www.youtube.com/watch?v=xtaqvKldUrs
Step 1: Getting Started
1) A full Metric and Imperical wrench set, sockets also.
2) Some angle Iron. (If your doing a complete rebuild)
3) Screwdrivers, Allen wrenches(Hex keys)
4) A welder, (again only if doing a full rebuild)
5) A reciprocating saw, a drill, amd various other power tools. (again for a full rebuild)
6) Other basic tools you will know waht you need once you get into it.
As for the ATV, prefferable one that doesn't run, or it is old and you don' t care about it's safety, do not use it if it has a 2-stroke requiring pre mixed fuel, only use this conversion on 4-stroke or 2-stroke oil injected engines.
For the propane system we used a weed burner with an adjustable valve to regulate the gas.
Step 2: Propane Conversion
This is the main step in the entire process, to start you need to find a suitable place to mount the propane injector, which is just a brass fitting we found. Basically you want it where it can mix directly with the flow of air but not have to pass through a filter, this is hard on new engines but hopefully you won't be converting a new engine. Although you could try and inject it straight into the air manifold and let it go through the filter. But anyway it works best when it is directly injected into the carb. Also this should only be performed on a 4-stroke engine or if your 2-stroke has direct oil injection, some 2-strokes require a mixed fuel and this will not work with the propane beacuse the propane has no lubricating properties like the mixed fuel and oil does.
Step 3: The Engine
Step 4: Drive System
As for the drive system everything on the original polaris was removed because it could no longer be used, so insted we mounted a jackshaft to the original mounting plate for the transmission. Once that is done a sprocket is needed to to tranfer the power from the jackshaft to the main drive sprocket. If you look at the picture it its a relatively simple setup for the drive system. A sprocket and centrifugal clutch would work better. But ours having a gear reduction we didn't think it would turn up enough speed to activate the clutch and we didn't build it for speed either. Having the pulley sizes like we have made an even larger gear reduction giving us a lot of pulling power but the belt doesn't have the frivtion needed to pull a lot of weight so it's kinda difficult to get it moving on an incline. The tension pulley is activated using a hand grip mounted to a handle.
Step 5: Drive System Cont.
Step 6: Electronics
Step 7: Aesthetics
Step 8: The Finish.
Now that you have your new creation it is time to enjoy it. Make sure everything is mounted up securely and if you choose to use a small propane tank make sure it is mounted good. Then if you can't disengage the drive system or your unsure about it block it up on a jack for starting. On our engine to start it you open thw gas valve until you can hear just a small amount going into the engine and then hold wide open throttle on the engine not the gas and crank it as soon as it starts then release the throttle and possibly adjust it to prevent stalling. As you increase the throttle you need to increase the gas flow to prevent stalling but not to much gas, it will take about a week to get it down and keep it running smoothly all the time. After that your pretty much done you can then add whatever else you want to it.