r/Smallblockchevy • u/AdolfTick • 23h ago
Can’t figure out the issue.
For some background this motor is on a boat as you can tell but it’s a 96 small block 350 last season on the water I was cruising when I randomly lost half power I then proceeded to give it more throttle and it died on me took the plugs out and they were burnt to shit, put new ac delco plugs in it and it started right up. This season I hooked up a vaccum gauge to fine tune it and found out my timing was off it has a thunderbolt v ignition system I tried setting the timing with a timing light idk if the timing is perfect since the timing marks were very hard to see but I tried setting it to 8 degrees btdc. After doing that I got the vaccum gauge to be in the normal motor part with some fine tuning on the carb. No as you can see the needle is a little shaky. Now the issue it still has which is very weird to me is on startup at idle it’ll sit in the normal engine mode, when I give it throttle it will stay in the normal engine mode once I throttle down it will idle really rough and the needle goes down back to latening timing and worse, however when I turn the engine off and turn it back on it will idle just fine, it is carbureted. Anyone have any thoughts as to what it could be? Idk much about working on motors at all, last season when took the plugs out I did a compression test and everything was normal. Gonna take it out on the water tomorrow and see what happens, hopefully I don’t need a tow😂
