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FSH loosing speed and power

fishkiller7

Active Member
Messages
8
Reaction score
0
Points
40
Boat Make
Yamaha
Year
2019
Boat Model
FSH Sport
Boat Length
21
Hey Last Summer hit 42 mph easily this year maxing out at 25 What? suggestions appreciated thanks
 
Where are you?
What rpm are you at WOT?
bilge pump working much?
Any different sounds/vibrations?
Checked the oil level?
Is the bottom hull clean?
Pull the impeller for inspection and measure gap
 
Did boat sit over winter?
Did you use/add any fuel supplement?
How much fuel have you used this summer so far?
 
Where are you? Pensacola FL Bay
What rpm are you at WOT? top RPM 8 but then bounces up and down
bilge pump working much? bilge is working
Any different sounds/vibrations? not that i can tell sounds all out and good but no speed
Checked the oil level? no but will
Is the bottom hull clean? not bad some barnacles
Pull the impeller for inspection and measure gap - will try this but not sure what you mean about the gap

BTY thanks for your help
 
Did boat sit over winter? yes but added stabilizer with low amount under 15% fuel
Did you use/add any fuel supplement?
How much fuel have you used this summer so far? about 180 gallons
 
Did boat sit over winter? yes but added stabilizer with low amount under 15% fuel
Did you use/add any fuel supplement?
How much fuel have you used this summer so far? about 180 gallons
Did boat sit over winter?
Did you use/add any fuel supplement?
How much fuel have you used this summer so far?

there is fishing line braid around impeller how bad is it to run it with it on there?
is that effecting the speed that much?
 
If you are hitting 8000 on both engines and only 25 mph there is an issue with the impeller. Either something stuck, weeds, etc. We boat there often (May, and we’ll be down again in 3 weeks) and I can hit high 30’s with 6 adults and 4 kids aboard.
 
Get the fishing line off there, then test again. The gap from the impeller to housing should be less than a credit card thick.
 
there is fishing line braid around impeller how bad is it to run it with it on there?
is that effecting the speed that much?
Not bad that you'll break something but definitely could be a performance issue,

Look in the faq section on how to pull your pump,

Do both tachs bounce or just one?
How much do they bounce?
 
both bounce starboard side less frequent port non stop
 
Not bad that you'll break something but definitely could be a performance issue,

Look in the faq section on how to pull your pump,

Do both tachs bounce or just one?
How much do they bounce?



One other thing i found interesting.... is going all out on each throttle seperatly they reached the same speed 9 mph etc with the fishing line in one side I figured it one engine would preform worse.
Does that tell you anything?
Thanks again for your help
 
In my experience when my tach bounces its because I have grass in the grates or the impeller. It doesn't take much to affect the holeshot but takes more than I would expect to affect top end speed. Is it reaching 8k rpm while going wide open or just the holeshot? Also, is it really going slower or could it be the paddlewheel sticking? Have you checked it against a gps?
 
Also for a data point, with a grapefruit sized clump of seagrass in both grates, 6k rpm cruise slowed down from 30 mph to 20 mph on my 210 FSH, didn't try WOT though.
 
there is fishing line braid around impeller how bad is it to run it with it on there?
is that effecting the speed that much?


The fishing line is the culprit, I run into this all the time and the result is always speed reduced. Since it's not clogging the impeller, it won't overdrive, but will put a load and not let you get speed.
 
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