Hello. I'd appreciate some input. '66 Chrysler 105 hp. Engine is running great. Last weekend it started throttling back after 10 seconds. If I go slow, it's fine. If I speed up it will eventually roll back. I have to pull throttle back and re-engage. The filter looked pretty bad so changed it. Took it out today, sure it would be fine. It wasn't. It maybe runs a few seconds more than it did last week. Maybe 15 seconds. Help. What should I check next?
Could also be a bad fuel pump. If you pump the primer bulb and it runs better, very likely the fuel pump diaphragms are weak and/or there's debris in the pump check valve(s) and that'll effect pumping.
Thx. Getting some ideas. Seems so obvious now. Also, the filter bulb wasn't filling up when running at speed. It was just settling in the bottom 1/4th. I think you're right. Clog upstream somewhere or vent clog. Thx.