[antiRepublicrat]

You can simply filter and preheat the fryer oil if you don't want to use the lye treatment process.

For that you need to modify the engine. Plus you don't get all that glycerine leftover. That plus a little more lye and some more pure fat can put you in the melt-and-pour soap business.

Or you can just break out the old chemistry set and start blowing stuff up. :)

[radioman]

For that you need to modify the engine

No engine mod needed. Stick the preheater in your trunk. Start the engine on diesel and switch over when the preheater gets up to temp. Switch back to diesel and let the vegetable oil clear the system before you shut down. It's a hassle but it works.

That plus a little more lye and some more pure fat can put you in the melt-and-pour soap business

LOL!
Great idea...Sell soap to help pay for the fish oil!
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