I'm either about to lose my mind or my hair over this one. I need some gurus to help me sort this thing out. About a year ago I swapped in a '73 vintage 360 from a Class C Motorhome into my IH Scout 2. It was a great running 90k mile motor and trans, and the install was a snap really. Even with the problems I'm about to lay out, it still idles as sweet as a 90k mile motor should.
I meticulously went through the wiring to make the Chrysler alternator, voltage regulator and electronic ignition, work with the GM style wiring the Scout has, including an ammeter bypass.. After I started to drive it, I noticed a little bit of a surge and sputter during cruise. I bet on a bad carb, and bought a kit. It didn't seem to help.
So I looked into the ignition. One piece at a time I go after it. Reman distributor, new module and coil, and even a new ignition switch. Nada.
So now I replace the spark plugs, check the cap, rotor and wires, and find,..... still nothing.
Then I start to think vacuum leak. I sprayed starting fluid everywhere, nothing. I replaced a couple of small vacuum lines that might be an issue,.. nada. No change without the brake booster attached even!
Then a friend suggested grounds. I add a bunch of grounds and clean up the ones I have. Still nothing. So it has been mostly parked. I had to drive it the past couple of days, so I filled it up with fresh gas and took off. It's even worse. So much so that it misfires randomly out the exhaust, especially on deceleration!
What am I missing? Please help, I haven't much sanity left. Thanks!!