My boat just sat for two years. The gas smelled horrible. I siphoned it out, blew out the lines and with new gas it was no issue. I mixed one part of this crap gas with 2 parts new gas for lawn mower use. The mower runs but it's not happy with 1/3 crap gas. My pickup truck sat for almost a year and It started but with the old gas will not climb a hill. I had to dilute it down with high octane to get it to behave

Todays gas does not have the 'stay' power of gas from the 80's. It may start, but with the octane levels in the toilet, it may not do much more then idle.

I think I would siphon out what I could, Add fresh to it. Unhook the the hose in the back of the Fuel regulator and turn the Key to the ON position a few times and let the Fuel pump carry the fresh gas to that point before hooking it up and trying to fire. Then as Randy said. Let the fluids circulate before hitting the highway. A nice idle down the road would let the axle bearings circulate grease and oil too.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html