Hi everyone!
I recently bought a -99 BF8A (the flat top) that was really cheap because it needed some work: Cracked lower swivel bracket, and a handle-bar that came off all the time, both easy fixes. The seller also said the engine stops after running a while. It's been running in brackish/fresh water.
As I got the engine, I cleaned the carb thoroughly (not the factory sealed nozzles though) and fixed the other stuff. I've also read about stuck thermostat being a common issue with these engine so I replaced that one as well (yes, it was stuck open), and also the inlet/outlet gaskets which came apart when I removed them.
I've been running it in a barrel for at least 1 hour total. It starts in max two pulls, and it's been running really nice with no idling issues and smooth in every RPM. So this weekend i tried it on the boat, and it ran great for about 4-5 minutes after which it died. It didn't just cut of, but revved down to nothing in about 3-4 seconds. One pull on the starter and it ran again, but died after a few seconds. It got harder and harder to start and after the third time it needed choke to get it running, but even with choke it died after a few moments. It feels like it's fuel starvation but cannot be sure.
When I got home I put it in the barrel again. I immediately checked the sparks and they were kind of medium ash-grey. The engine was still grumpy, hard to get running. and when it ran it wouldn't rev, so I checked the fuel pump and filter (no problems, with a pulsating stream of fuel from the filter). I drained the float chamber which was full, and blew into fuel line (bubbling sound, no blockage).
After some more pulling the engine idled again and very soon it ran as normal.
Since it does run fine in a barrel, it seems the problem appears when the engine have to do some actual work. Overheating seems to be out of the question since there's a strong stream from the tell-tale and the engine was cool, but still not running well, when I got home.
Anyone got any ideas where to continue troubleshooting? Any tips much appreciated.
I recently bought a -99 BF8A (the flat top) that was really cheap because it needed some work: Cracked lower swivel bracket, and a handle-bar that came off all the time, both easy fixes. The seller also said the engine stops after running a while. It's been running in brackish/fresh water.
As I got the engine, I cleaned the carb thoroughly (not the factory sealed nozzles though) and fixed the other stuff. I've also read about stuck thermostat being a common issue with these engine so I replaced that one as well (yes, it was stuck open), and also the inlet/outlet gaskets which came apart when I removed them.
I've been running it in a barrel for at least 1 hour total. It starts in max two pulls, and it's been running really nice with no idling issues and smooth in every RPM. So this weekend i tried it on the boat, and it ran great for about 4-5 minutes after which it died. It didn't just cut of, but revved down to nothing in about 3-4 seconds. One pull on the starter and it ran again, but died after a few seconds. It got harder and harder to start and after the third time it needed choke to get it running, but even with choke it died after a few moments. It feels like it's fuel starvation but cannot be sure.
When I got home I put it in the barrel again. I immediately checked the sparks and they were kind of medium ash-grey. The engine was still grumpy, hard to get running. and when it ran it wouldn't rev, so I checked the fuel pump and filter (no problems, with a pulsating stream of fuel from the filter). I drained the float chamber which was full, and blew into fuel line (bubbling sound, no blockage).
After some more pulling the engine idled again and very soon it ran as normal.
Since it does run fine in a barrel, it seems the problem appears when the engine have to do some actual work. Overheating seems to be out of the question since there's a strong stream from the tell-tale and the engine was cool, but still not running well, when I got home.
Anyone got any ideas where to continue troubleshooting? Any tips much appreciated.