Ol' Roy has been sitting more or less idle since the end of June. It was out at my mom's house because I needed his usual spot temporarily for another vehicle.
Anyway, it started and drove normally - nice and smooth with no fuss.
I drove about 15 miles to top off 18 gallon tank at Sam's Club before getting on the freeway. It only took about 6 gallons of87 deathanol - the fuel which Ol' Roy has been using nearly exclusively for the last 4000+ miles.
I got on the highway and accelerated up to cruising speed of ~55mph. So far, nothing out of the ordinary.
About 5 miles down the road after crossing the Chattahootchee River, the highway starts a long, but not steep, incline.
At some point the truck seemed to be losing power almost like you'd experience with a slipping clutch or if the engine was starving for fuel. In the split seconds while my brain was trying to figure out what exactly was happening, I let off the accelerator and there was a sudden LOUD CRACK! which I felt through the floorboard.
I thought the transmission exploded but quickly determined that wasn't the case. I looked in the rearview mirror and saw through the beams of light from the cars behind me (who were themselves, slowing down and backing off) a cloud of smoke.
This was at night so I couldn't tell you what color the cloud was but I figure it was black. After my brain caught up with events, I determined/assumed that the truck had backfired and likely shot a flame out the tailpipe, which scared the people behind me enough for them to put some distance between themselves and my bumper.
After that the truck showed no other problems. Several more hills - steeper that the last one - had no effect on the engine at all. It didn't lose power, didn't stutter, didn't backfire, or anything.
When traffic got heavy on the downtown connector and I had to slow down to 10-20mph, the engine ran just as smooth as ever.
This morning I checked over the truck thoroughly. No hole in the muffler, no water in the oil, oil full, radiator full, no visible debris in glass fuel filter bowl. Truck started right away and idled smoothly with no smoke from the tailpipe or anything else out of the ordinary.
I suspect maybe water/debris in the fuel I had just put in the tank but who knows?
Do any of you have any ideas of what likely happened? As I drive the truck from this point forward I'll soon learn if that was a fluke or of there is some endemic problem.
Just FYI, tank and lines are new. Pump and carb are newly rebuilt with over 4000 miles on the carb and probably 3000 or more on the pump. Points were replaced a couple weeks ago.
