I realize that this info has a limited use to most readers of this site but decided to post it anyway. After doing some research on the melt points of polypropylene, and finding some sites that specialize in the equipment to weld various types of plastics, one of them being polypropylene, I decided to experiment with a poly drum, 1/4" poly tube for a fill rod, and a hot air gun that we use for some of our experiments in the plant. Even with the wide nozzle on the stock heat gun, I was able to successfully weld a long hole in the barrel top shut, although a smaller nozzle will have to be fitted to prevent over heating the surrounding plastic.

I am going to try this on the 780 gas tank this weekend before removing the tank(which will be flushed with water for safety) and will post some pictures afterward.

Regards,

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Will Dallas, www.willdallas.us, www.willdallas.org, www.willdallas.com, www.dallasprecision.com 86 245 DL 222K miles, 93 940 260K miles, 88 765 GLE 152K miles, 88 780 246K miles