hairdresser100
Contributing Member
Hi All,
I use my twin engine Boat to make my living and I need your professional help Hondadude / Master Techs! This is my busy season and my 1997 Honda BF90 failed me today.
I was cruising along in horrible conditions and the boat felt like it lost power and the waves had more control of me than I had on them. Long story short, my starboard 1997 carb Honda BF90 lost power. It struggles to get to 4k RPM and getting on plane takes forever. I have to push the throttle lever almost wide open to keep 4k. 4200 RPM is max wide open now. The fuel flow meter usually says 3.9 to 4.4 GPH and it's now it's in the mid to high fives. The motor is drink tons of gas to keep 4k RPMs and will fall if you hit a wave or....
I'm good with outboards and have a parts engine and Honda factory service manual. I just walked in and I'll start reading now but I must work tomorrow......with the boat!
-Hanging over the stern I dumped the fuel from each carb.
-Pulled each spark plug wire and heard "zapping sounds" from each. Certain cylinders caused the engine to stumble more then the rest.
-I chocked the bad motor when at 4k and the motor didn't like that. RPMs dropped for a second or two.
The engine starts fine. Idles fine. Doesn't shake. Doesn't pop, studder or.......
When I was flushing the motors at the ramp the bad motor's T stat housing and head felt hotter to the touch. No overheat alarm and pisses great. I installed new water pumps last year. The dash lights show green, all is well.
I have new (last year) fuel filters in the engine and racors before the engines.
What do you think? Thanks!
I use my twin engine Boat to make my living and I need your professional help Hondadude / Master Techs! This is my busy season and my 1997 Honda BF90 failed me today.
I was cruising along in horrible conditions and the boat felt like it lost power and the waves had more control of me than I had on them. Long story short, my starboard 1997 carb Honda BF90 lost power. It struggles to get to 4k RPM and getting on plane takes forever. I have to push the throttle lever almost wide open to keep 4k. 4200 RPM is max wide open now. The fuel flow meter usually says 3.9 to 4.4 GPH and it's now it's in the mid to high fives. The motor is drink tons of gas to keep 4k RPMs and will fall if you hit a wave or....
I'm good with outboards and have a parts engine and Honda factory service manual. I just walked in and I'll start reading now but I must work tomorrow......with the boat!
-Hanging over the stern I dumped the fuel from each carb.
-Pulled each spark plug wire and heard "zapping sounds" from each. Certain cylinders caused the engine to stumble more then the rest.
-I chocked the bad motor when at 4k and the motor didn't like that. RPMs dropped for a second or two.
The engine starts fine. Idles fine. Doesn't shake. Doesn't pop, studder or.......
When I was flushing the motors at the ramp the bad motor's T stat housing and head felt hotter to the touch. No overheat alarm and pisses great. I installed new water pumps last year. The dash lights show green, all is well.
I have new (last year) fuel filters in the engine and racors before the engines.
What do you think? Thanks!
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