I have a 2000 225HP Optimax that is running like crap under way / load. It starts, idles and revs perfect but in the water it starts breaking up / surging at around 1200, wont really accelerate unless I floor it then the engine will surge a few times and then accel hard to near 3K, when it hits 3k its not sounding like its on a rev limiter but more like the engine is maxed out, I have the throttle all the way open but thats all it has, it will run 3K for a second than drop to 2500, then slowly bog it self down over a several minutes running worse and worse even with leaving the throttle at WOT.
So far I have done...
Replaced all filters
Opened the VST - looked clean, no debris or fuel hose bits
Checked pressures - I got 92 fuel, 82 air, 6-ish low pressure
I checked spark with a gap tester and it jumps 3/8 in no problem on all 6
I pulled the injector connectors one by one and each made the engine run rougher so all 6 are firing
Rebuilt the pulse pump on the side of the block
Pulled the low pressure pump connector and PSI dropped from 6PSI to 0
Pulled the high pressure pump connector and it instantly stopped running
Compression cold is 90ish on all 6, my understanding is doing the special optimax method will yield 20% higher
Plugs not fouled but noted each one had a little bit of wet oil on them, probably from incomplete burn
Tracker and diphram both replaced last year
Cobia season is coming! Please help!
Any ideas of what else to check / replace?
Vids...
surging with gauges... https://streamable.com/3zjz5x
1200 to WOT... https://streamable.com/xy6lr4
So far I have done...
Replaced all filters
Opened the VST - looked clean, no debris or fuel hose bits
Checked pressures - I got 92 fuel, 82 air, 6-ish low pressure
I checked spark with a gap tester and it jumps 3/8 in no problem on all 6
I pulled the injector connectors one by one and each made the engine run rougher so all 6 are firing
Rebuilt the pulse pump on the side of the block
Pulled the low pressure pump connector and PSI dropped from 6PSI to 0
Pulled the high pressure pump connector and it instantly stopped running
Compression cold is 90ish on all 6, my understanding is doing the special optimax method will yield 20% higher
Plugs not fouled but noted each one had a little bit of wet oil on them, probably from incomplete burn
Tracker and diphram both replaced last year
Cobia season is coming! Please help!
Any ideas of what else to check / replace?
Vids...
surging with gauges... https://streamable.com/3zjz5x
1200 to WOT... https://streamable.com/xy6lr4
