rmonheim94
Active Member
Hi All,
I've got a 1996 Speedster with a suspected fueling issue that I cannot figure out.
After a warm restart on the port engine, the first time you throttle between ~10%-30% it will hesitate for about a second before accelerating further. Sometimes it will die if you continue to give it more throttle. It ONLY does this on the first acceleration following a restart, once it has happened once, it does not ever occur again until the engine has been restarted. Other than this issue, it runs very well at all speeds/loads. I rebuilt the carbs over the winter using the "Back to OEM" kits from OSD. I cleaned them very well, and have pulled them off since I noticed this issue and confirmed that all passages are clean/clear. As far as I know, this problem did not occur at the end of last season right after I purchased the boat but before I touched the carbs. Some other notes below...
My best guess/theory right now is that for some reason the fuel pump is not pressurizing very well, but once you get it pumping at higher engine speeds, it holds fuel pressure and the problem goes away. I'm thinking that lowering pop off might help, but I shouldn't need to do that on a stock engine. I'm pretty stumped at this point and open to any suggestions/ideas. Thanks!
I've got a 1996 Speedster with a suspected fueling issue that I cannot figure out.
After a warm restart on the port engine, the first time you throttle between ~10%-30% it will hesitate for about a second before accelerating further. Sometimes it will die if you continue to give it more throttle. It ONLY does this on the first acceleration following a restart, once it has happened once, it does not ever occur again until the engine has been restarted. Other than this issue, it runs very well at all speeds/loads. I rebuilt the carbs over the winter using the "Back to OEM" kits from OSD. I cleaned them very well, and have pulled them off since I noticed this issue and confirmed that all passages are clean/clear. As far as I know, this problem did not occur at the end of last season right after I purchased the boat but before I touched the carbs. Some other notes below...
- Compression is ~135-140 psi
- Starboard engine does not seem to have the problem
- Tried new spark plugs right before a warm restart to confirm it's not fouling plugs
- Tried disabling charging system
- Popoff confirmed 55psi on both carbs, fuel pumps tested by mouth
- All new fuel lines, cleaned selector, water separator, pickup, etc
- Pulling the choke seems to help some when issue occurs
- Going straight to WOT after warm restart generally does fine
- Tried low speed needles in/out up to a turn without any real improvement
- Port engine does have slight leak into RV cavity, but the only symptom is excessive smoking after startup after sitting a few days
- I know I've tried other things that I can't remember right now...
My best guess/theory right now is that for some reason the fuel pump is not pressurizing very well, but once you get it pumping at higher engine speeds, it holds fuel pressure and the problem goes away. I'm thinking that lowering pop off might help, but I shouldn't need to do that on a stock engine. I'm pretty stumped at this point and open to any suggestions/ideas. Thanks!
