My holeshot is more like a dribble

[Thor]

A bit of an overstatement. It still comes out strong but not the way it used to when I could send people sliding down the seat to the back of the boat. Top speed is still all there, easy to break 50mph. Only 80 hours and recently serviced, runs smooth. Do I need to check the impellers?

 

[swatski]

A bit of an overstatement. It still comes out strong but not the way it used to when I could send people sliding down the seat to the back of the boat. Top speed is still all there, easy to break 50mph. Only 80 hours and recently serviced, runs smooth. Do I need to check the impellers?

Eihter that, or more likely cavitation due to missing sealant in the intake tunnel and/or between the pump segments and/or transom- transom plate. Impeller OD is also critical and when it gets out of wack you can have that kind of "slippage". You should not be able to slide a credit card between the impeller and the wear ring surface (SS liner).
Could you post some pics of the pump interior, if you can stick a phone in there through the intakes, cleanout ports, and peer through the steering nozzles.

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[Thor]

Thanks @swatski I will take some photos next weekend. I found many videos on inspecting and replacing impellers, not much about the sealant.

 

[swatski]

Thanks @swatski I will take some photos next weekend. I found many videos on inspecting and replacing impellers, not much about the sealant.

I would think @gmtech16450yz tunnel porting (post #39? in this thread: https://jetboaters.net/threads/pump...ying-something-taboo.15594/page-2#post-271807) is one of the best I've seen.
Definitely labor of love, but can help a ton with hole shots and pulling, especially if using ballast.

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[Thor]

@swatski , my photos are not the best, what do you think?

 

[swatski]

Looks good... from what can be seen. There is nothing obvious.
but if you are concerned, I would just pull the pumps and poke around, reseal anything where air can be sucked in - inside the tunnel and between the transom plate and the transom. Many times a gap will be tiny.

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[Thor]

Thanks a million. The photo is poor but there is a chunk of sealant missing on the port tunnel, 3rd picture. Anything to be concerned about? I can try to get a better shot is needed.

 

[swatski]

That could be an issue, hard to tell with the pic.

There is only one way to find out! Clean it out and redo with 5200 or marine tex or whatever you think will stick and hold!

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