Date Posted:12:39:01 03/11/03 Tue Author:Phil Subject: Re: Won't plane In reply to:
Martin
's message, "Re: Won't plane" on 21:53:32 11/20/02 Wed
>>I have a 1996 Bayliner Jazz with a 120 mercury sport
>>jet. The motor runs smooth but the boat won't plane
>>with two people in it unless you put one in the very
>>front. I had Bayliner put a new impeller and sleeve in
>>it but it still won't plane any better. Any ideas?
>
>Exhaust gas leaking from the bottom of the boat can
>get sucked into the jet pump and cause it to cavitate.
>Check the screws holding the ride plate on and the
>gasket around the edge of this plate. The ride plate
>is the big black aluminim plate on the bottom of the
>boat. Exhaust gas can leak from the gasket around the
>outer edge of the plate or from the edge of the
>"window" in the middle of the plate where your intake
>grate is mounted. You can try some silicone sealer on
>these areas if you suspect leakage. It won't last for
>long, but will tell you if this is your problem.
I have no answers for your problem, but rather I have the same problem with my 1993 bayliner jazz (90HP). I think it just isn't pumping enough water to develop the thrust needed to perform like it is supposed to. It will get on plane with just one person on board, but the second person has to sit up front to get on plane. She'll only run about 31 mph with just one person.
I just had the engine checked out - good compression, good spark, and they cleaned the carbs. There is no tach so I'm not sure how fast the engine is turning. Anyway, I performed a visual inspection on the jet pump impeller and wear ring and they have a very close tolerance (less than 1/16 inch - I recently replaced a wear ring on one of my jetskis, and there was about a 1/4 inch gap between the impeller and wear ring and it made a huge difference in performance). So now I'm at the end of my rope.
I have a Jazz from 1996 with 120 HP. I have the same problem that it takes a lot of time to plane. Sometimes when I give full gass to the engine it goes in plane with 2 persons. Normally I have to but the second person in front for a while. Have you other guys solved the problem? Please reply.. I am living in Norway and I think there might be 8.or 10 boats like this all over Norway so it would be very find to have som international help.
Thank you !
>>>I have a 1996 Bayliner Jazz with a 120 mercury sport
>>>jet. The motor runs smooth but the boat won't plane
>>>with two people in it unless you put one in the very
>>>front. I had Bayliner put a new impeller and sleeve
>in
>>>it but it still won't plane any better. Any ideas?
>>
>>Exhaust gas leaking from the bottom of the boat can
>>get sucked into the jet pump and cause it to cavitate.
>>Check the screws holding the ride plate on and the
>>gasket around the edge of this plate. The ride plate
>>is the big black aluminim plate on the bottom of the
>>boat. Exhaust gas can leak from the gasket around the
>>outer edge of the plate or from the edge of the
>>"window" in the middle of the plate where your intake
>>grate is mounted. You can try some silicone sealer on
>>these areas if you suspect leakage. It won't last for
>>long, but will tell you if this is your problem.
>
>I have no answers for your problem, but rather I have
>the same problem with my 1993 bayliner jazz (90HP). I
>think it just isn't pumping enough water to develop
>the thrust needed to perform like it is supposed to.
>It will get on plane with just one person on board,
>but the second person has to sit up front to get on
>plane. She'll only run about 31 mph with just one
>person.
>
>I just had the engine checked out - good compression,
>good spark, and they cleaned the carbs. There is no
>tach so I'm not sure how fast the engine is turning.
>Anyway, I performed a visual inspection on the jet
>pump impeller and wear ring and they have a very close
>tolerance (less than 1/16 inch - I recently replaced a
>wear ring on one of my jetskis, and there was about a
>1/4 inch gap between the impeller and wear ring and it
>made a huge difference in performance). So now I'm at
>the end of my rope.
>
>Any ideas would be appreciated.
