While I was driving Glinda home from work yesterday, I noticed the tachometer needle would jump up while accelerating (even slight acceleration). The needle jumps up a few hundred rpm and then quickly falls back. It happened quite frequently and it appeared to have a slight miss when it did it. Soon after arriving home, I grabbed my tablet and posted my problem on Virtual Vairs. Within minutes, I received a reply from Mark Durham positing a faulty points plate. As soon as dinner was over, I donned grungies and headed out to the driveway where Glinda awaited.
Diving into the distributor, I pulled the plate and confirmed it was unmodified – no provisions to improve grounding. Ringo gave up his points plate – one that a ‘vair vendor had modified with a wire brush around the pivot to improve grounding. Before installing the replacement plate I cleaned the points with a quick swipe of fine sandpaper. Once the plate was in place, I adjusted the dwell to 32 degrees, put the rest of the distributor together, and set the timing to 16 degrees BTDC.
The subsequent test drive showed smooth action by the tach needle – success. There was still some hesitation under WOT at higher rpms in third gear. It wasn’t until this morning’s commute that I could check out the performance in fourth gear. There's still hesitation in fourth gear preventing me from getting much above four grand in the short bursts available to me.
Also somewhat disconcerting is the steady drop of the fuel gauge needle. Granted I’m doing a lot of WOT runs, but I’m still thinking the engine’s running rich. While I’ll be taking a pair of carburetors with me to New York, it’s doubtful I’ll do the swap until after the weekend.