Good Evening,
I decided to take the shot-gun approach and replace everything that 'could' be an issue. My thinking being if it fixed the issue, great, and I can always go backwards to see where the issue was; or not. If it did not fix the issue, at least we would know that new parts everywhere in the ignition 'should' eliminate the ignition as the issue.
As my coil is long obsolete, my parts guy crossed it and had the crossed coil in stock. It is a 12V coil. NO EXTERNAL RESISTOR NEEDED is printed on the coil. Furthermore, the instructions say in bold print NOT TO USE WITH A RESISTOR OR RESISTOR WIRE. So, new coil - check.
I removed the old points and while they were not perfect, they were not the worst I have seen. There was, however, evidence of arcing. I am not sure I would say pitted, but certainly not great. So, new points - check.
I did not bother testing the old condenser, since I was going for parts and they are - in the big picture, rather inexpensive. I will check the old condenser and see what it shows on a meter. So, new condenser - check.
In reading online I found the points should be set to .016 for this motor. Points are set to .016 with feeler gauge. While setting the points I noticed the rotor can spin - if I try to spin it - almost enough to come off a lobe. Not quite, but almost. Is that too much 'free' rotational movement? It is moving the entire shaft, it's not the rotor moving on the shaft.
The motor seems to have more power and after the longest drive around the countryside, including some decent hill climbs, I would say the issue is less prevalent, yet not completely gone. After 15, or so, minutes of driving I believe I have less power. Additionally, when I am really into the foot feed and let off, I get a backfire. This happens whether driving and letting off the foot feed or revving the engine and letting off. The backfire is out of the exhaust, not the carburetor, as I tested after dark to be sure. I am not sure if it matters, but it is a backfire on one of the last three (3) cylinders, as it comes out of the the 'back' manifold.
There is a noticeable hesitation coming off idle if you goose it. If you roll into the foot feed, it is smooth all the way from idle to red line. (I have no idea what red line is, as I do not have a functioning tach, but suffice to say it is as wide open as it will go.) If you goose it, you can just about stall it, if you do not let off the foot feed. This is not a new issue, just an issue I did not previously mention.
I did NOT gap the plugs before the test drive. I did pull them, once things cooled off a bit, and set all of them to .039, which is what I found online. (Between .036 and .040 is what I read.) All of the plugs looked exactly the same. I would describe them as tan in color on the electrode (both center and side - if that makes sense) and black on the ring around the bottom, below the threads. I can post a photograph if my description is not painting the picture. It is worth note that all of the plugs were gapped to @.019 when I pulled them.
I am all ears on where we go next and expect, I think, it will be the carburetor. Since we may be going here, and I am not sure why this just now dawned on me, it is worth mentioning that I am running a Rochester B - single barrel carb, with the hot-air choke. A massive air cleaner, which looks like an old oil-bath, but is not. I have not the first idea if it is correct, but it came on the engine so I have been using it. Again, if photographs of any/all of this is helpful, please let me know and I will take and post them.
Thanks,
Joshua L. Coder
