I did some quick troubleshooting yesterday with the timing and found that my timing gun was set to 10˚ advanced, so the truck is still way ahead of where it should be. It’s also dieseling when I shut it down, which tells me the timing is way too advanced. On our truck text thread the other day, Bennett gave me some things to check over:
- Time it with vacuum advance disconnected and plugged. Done. It seems happiest when it’s waaaay advanced.
- Are they the correct spark plugs? And gapped? Yes!
- How’s the points gap? The gap looked good to me, but it’s hard to get a gauge in there with the condenser and mechanical advance in the way.
- Have you set the dwell? This one I need to do some more research on. Two weeks ago I tested it and found that it was at 26˚ when it should be 30˚, so some adjustment is required there.
- Does the timing mark jump around when you add throttle? No, it’s smooth, which is a good sign.
- Spray carb cleaner around the carb base and ports to test for vacuum leaks. I didn’t get to this one.
- Does the timing mark advance as you add throttle (with vacuum plugged) to test mechanical advance. Check—working as designed.
But she’s still not running correctly, so more diagnosis is required. And until I get the mechanical fuel pump fixed and installed, I’m going to need to wire the electric unit into the switched power fuse panel, because I keep forgetting to turn the damned thing off when I shut the truck down.
In retrospect, I’m very happy I decided to remove the Sniper and go back to the basics, because I would have been smashing my head against the wall for months trying to diagnose software when this a mechanical problem to begin with.