Low hour 200 JUST WONT JUMP

[skaha skier]

Just picked up a 2010 ski nautique 200.Very low hours 83.I think for the first 5- 6 years some use but the last four or 5 basically summarized/winterized but just sat on the lift.
she just doesn't accelerate well (my 2003 nautique 206 puts its to shame)and top end only 32/33 mph(3500)
have changed both the inline and fcc filters.
put in new high pressure pump today
have put 2 tanks of premium fuel( 1 with injector cleaner through it)
plugs look good - if any thing a little lean
starts beautifully/idles nicely/no misfires/backfires
Sounds fine coming up to speed albeit pretty sedate - just plateaus- more throttle does nothing-just bit louder
seems starved for fuel ?/? for air
no codes on the onboard

? flame arrestor/injectors(?all of them)
What' next

[NautiqueJeff]

What prop is on the boat?

[skaha skier]

409 zr
prop = 4 blade 654 12.5 by 15 stock I think

I suspect sitting on a lift for years /not running/old gas must have something to do with it
? varnish- gumming up/constricting the fuel injectors

interestingly gains a couple hundred rpm with engine cover up - cleaned the flame arrestor - will see

will try some more fuel injector cleaner/conditioner through and see - does seem to gain a bit more power/rpm under load each time
but a long way to go

[bruce.hartman.96]

You may want to check your PVC tube and boots. I had a similar problem and found leak there on my 200.

[skaha skier]

She JUMPS NOW

turns out it was the ignition side
pulled the plugs again turns out they are all gapped .033/ only 1 plug a bit of carbon
grasping at straws bought a new set of Ac deco 41-110
out of the box gapped .033?? Hmmm - recommended everywhere .04
I gapped them all .04 and BINGO - she goes like ****
somebody just put the original set in as they come in the box ( I don't think that one plug was the culprit)