• Welcome to Jetboaters.net!

    We are delighted you have found your way to the best Jet Boaters Forum on the internet! Please consider Signing Up so that you can enjoy all the features and offers on the forum. We have members with boats from all the major manufacturers including Yamaha, Seadoo, Scarab and Chaparral. We don't email you SPAM, and the site is totally non-commercial. So what's to lose? IT IS FREE!

    Membership allows you to ask questions (no matter how mundane), meet up with other jet boaters, see full images (not just thumbnails), browse the member map and qualifies you for members only discounts offered by vendors who run specials for our members only! (It also gets rid of this banner!)

    free hit counter
  • Guest, we are pleased to announce that Hydrophase Ridesteady is offering an extra $100 off for JETBOATERS.NET members on any Ridesteady for Yamaha Speed Control system purchased through March 7th, 2025. Ridesteady is a speed control system (“cruise control”) that uses GPS satellites or engine RPM to keep your boat at the set speed you choose. On twin engine boats, it will also automatically synchronize your engines.

    Click Here for more information>Ride Steady group buy for JetBoaters.net members only

    You can dismiss this Notice by clicking the "X" in the upper right>>>>>

Screech and knock....

Terrance

Jet Boat Addict
Messages
53
Reaction score
20
Points
97
Location
Porters Lake Nova Scotia Canada
Boat Make
Glastron
Year
2015
Boat Model
GT
Boat Length
19
Hi All. I own a 2015 Glastron GT187. We were out in medium lake chop today with 3/4 throttle and out of nowhere a load screech happened. We were cruising along in 7 meter depth. So no rocks or sucking up anything. I immediately hit the throttle back to nuetral. When I tried to throttle up again, I hear a load knocking sound. Any ideas?
 
Man don't know, is the knocking coming from the engine or somewhere else? Engine, pull spark plugs and check compression, any more details you can give us?
 
Thanks for the reply Genwrx.
I recently had a wear ring and impeller replaced. It's hard to tell if the sound is an engine or drive-line noise. Its like it is shuddering. The more I try to power up, the more the knock wants to happen.
I have 138 hours.
 
Sounds like something in the pump. Did you pull the boat out of the water to take a good look?
 
Sounds like the classic rope in the pump. Might have been an anchor line or dock line floating just under the surface and your giant vacuum cleaner found it.
 
Ended up that the splines at the end of the drive shaft were stripped. Dealer said they were damaged by the ingested rock that went through the impeller and wear ring. The odd thing about it, after the new wear ring and impeller install, we ran the boat for 6 hours before the splines issue became an issue????? another repair.
 
Is there a grease point there in your boat? In my seadoo from 1999 there was a zerk fitting to grease the splines but we didn't know so after many hours of no grease the rubber boot broke and later the splines gave.

Not sure how the new motors are, but grease here was very important to keep the shaft and pto splines from having this exact problem.
 
Is there a grease point there in your boat? In my seadoo from 1999 there was a zerk fitting to grease the splines but we didn't know so after many hours of no grease the rubber boot broke and later the splines gave.

Not sure how the new motors are, but grease here was very important to keep the shaft and pto splines from having this exact problem.
I would bet you hit it right on the head. Thanks
 
Back
Top