1997 150HP Ocean Pro Misfires

[jetcar123]

I purchased a 1997 150HP on a 21 ft seaswirl walk around. At first engine would not make more than 2000 RPM before check engine warning came on. T/S found bad hose to VRO from check valve. Replaced hose, rebuilt fuel system from tank to VRO, rebuilt VRO. Test run engine went to 5600 RPM no warings, but less than a minute the engine kicked violently, lost RPM than recovered than kicked again. As long as I keep the RPM below 3900 the engine runs fine all day. When I say "kicks" if you are not aware of what might happen when the engine kicks you would want to jump overboard. The entire boat shakes and you would sware the engine it going to leave the boat. It than recovers for about a minute until it kicks again. Plugs, plug wires, 3 coils, disconnected shift switch, ran engine with main harness disconnected, replaced igntion switch, eliminated safety lanyard, set timming, check adjustment on all linkage, checked output of power pack, adjusted carb idle mixture, and check cylinder temp at 3900 RPM at spark plugs all no help. The only thing that did help a little was replacing thermostats since engine was running cold. RPM now goes to 4200. Any ideas?

[JUST-IN-TIME]

sounds like the carbs are gummed up

try pumping the primer bulb
if it picks up you have an air leak'
bad primer bulb
bad fuel pump

[jetcar123]

Thanks, I've tried all of that no help, but I am going to rebuild carbs in spring because I just can't get the engine to idle right. I'll look at the reeds while I'm trere also.

[JUST-IN-TIME]

ok cool you can always email me