Bad Acceleration to Plane from Start

[Jetboat4life]

This past weekend the boat would'nt plane like it used to (3 to 4 sec). Now it will just high rev on full throttle..almost like a slipping clutch in a car would feel like. I can go to 5krpm and it will go good..then gradually get to 8k where it still hits 48mph. Ive checked the ports and found no obstructions. What could cause this? I checked the impeller ports and didnt see any visible nicks scratches. Ive got about 110hrs on the boat. This would plane very quickly..now it takes about 10 to 12 sec to get going.

Any help would be great..any questions please let me know.

 

[Beachbummer]

Check for any loose of missing chunks of sealant around pump. Sometimes sealant is lost and it allows air into the pump, which can cause cavitation on hard starts.

 

[Jetboat4life]

do you have a picture for reference? Or point me in the right direction..

 

[Scottintexas]

I agree with bummer, I would also pull the impeller shafts out just to get a better look at everything, it's only a 15 minute job and something good to be familiar with

here is a link to my missing sealant issue,

https://jetboaters.net/threads/cavitation-missing-sealant-in-pump-grate.884/

.

 

[John Mcpartland]

have you been in any sand lately? I was stuck in some low sand a while back and gunned it to get out and had the exact same symptoms. replaced my impellers and been good since. the sand sanded or bent my impellers just enough to be out of spec, they still look brand new. you can check with a feeler gauge

 

[props2you]

Any other symptoms while accelerating? Louder than usual, vibration, etc.?

 

[Jetboat4life]

Im guessing they may just be out of spec..Is this covered under warranty?

 

[Jetboat4life]

Any other symptoms while accelerating? Louder than usual, vibration, etc.?

No vibrations. Just full throttle to 8k..it kinda hangs a little but then eventually planes. Still runs 45+. So I push it to 5k to get up and going then. We I hit about 35 mph I push it to 7.5k. Reverse feels strong If I can recall.

 

[Scottintexas]

I doubt impeller damage is going to be covered under warranty,
It's easier and less time to fix it yourself anyways, where are you at maybe a local member could help you,

I wouldn't discount the sealant or air intrusion without more investigation,

.

 

[Beachbummer]

Sorry, no pictures, but if you examine the surfaces where the pump meets the boat (much easier to do when you pull the pump out) you will see some sealant used to fill gaps around the fiberglass opening. It's generally obvious when it dislodges, and you can see a missing chunk of a piece of stingy sealant still half attached.

 

[Tailwaters]

Check your clean out plugs. I had a similar issue and it turned out the plug was not sealing up. Sprayed some silicon on it , reinstalled and problem solved.