Hey, no fear of hijacking this post. <img src="/forums/images/graemlins/smile.gif" alt="" />
Unfortunately, I can't tell you about the other Isuzu diesel engine models, as I only have experience with the C223. It looks like there are some nice alternatives out there, with much more power than mine (58hp). Newer, direct injection diesels are much quieter than the old indirect-injection types (like mine), are great on fuel, and usually start easier cold. My particular engine is of an old design, though reliable and simple. Look for something with a turbo for more power.
There are other possibilities as well, such as Toyota, which had a bigger diesel in their FJ series, Mercedes from an old car, which would have a transmission with it, and they are bullit proof. I've often thought I'd like to have a 4 cylinder version Cummins of the type used in Dodge trucks. I figure that should be fairly strong, though likely heavy, and probably noisy.
Conversion is possible, if you read the post I wrote before yours, it will give you some idea of what has to be considered. I'm sure there is more that I forgot.
I hope this helps in some way. Feel free to discuss this if you feel like it.
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