Lost thrust portside on the water… (keep up your cleanout plug maint.!)

[Zeusmotorworks]

On the water and lost thrust on the port side. No check engine lights no funky running. It’s almost like an outboard when you lose the prop. However everything looks fine both underneath and on top. Plugs all in and look functional. Is there a coupler that can go out on these?

<edit> found out it was my clean out port plug seal (Man hole covers or whatever Yamaha calls them). It was allowing air into the system and causing cavitation. Bought the rebuild kit and all is good again!

 

[Zeusmotorworks]

Got it back to the dock. So it will take off fine but once I get up to speed about 30 miles an hour just over 6000 RPM it’s like it starts cavitating. Wear ring?

 

[HangOutdoors]

Really sounds like something is in there. Could even be small. Look through the pump from bottom, top and back. I have had that several times and each time there was something in the pump. Weeds, small piece of plastic, small piece of wood.

 

[Zeusmotorworks]

Pulling it out tomorrow and bringing it to the house. However, on the lift in the slip I could see nothing looking back up the pump, nor could I see/feel anything via the clean out ports. Will a simple peice of debris cause power loss to be that dramatic? This my first jet anything and up til now has been completely trouble free other than a plastic bag in the other side a while back, and that caused a light til I got it out.

 

[HangOutdoors]

Yes it can. Look real hard it could be something small caught in there like a piece of wood chip.

 

[Zeusmotorworks]

Thanks... will do!

 

[sunbyrned]

100% something is in there. Even if you don’t find it, pulling the pump and impeller and putting it back together will probably do the trick.

 

[Zeusmotorworks]

Thanks, but thought the pumps on the newer little TR-1s where a little different? All still simple enough I'm sure. Bout to go yank it out of the water.

 

[Cobra Jet Steering LLC]

You may have a small piece of fishing line that is all it takes . I have one of the cameras with the long flexible cables that will allow you to look up in between the impellers and see since before you go pull the pumps often if it is a small piece of wood after a few days of being out of the water the wood dries out and shrinks allowing it to fall out. Plenty of posts in that regard in the search function

 

[Julian]

If you don't have a special camera, just turn on the light on your phone , start recording a video and stick the phone down the clean out port. Then SLOWLY move the around to pan over the impeller. Bet there is a small bit of wood in there.

Then buy hook blades for a utility knife and use it to carve out the wood (assuming you are on the water). If you can get it on the trailer....just pull the pump...it's easy.

 

[Cobra Jet Steering LLC]

If you don't have a special camera, just turn on the light on your phone , start recording a video and stick the phone down the clean out port. Then SLOWLY move the around to pan over the impeller. Bet there is a small bit of wood in there.

Then buy hook blades for a utility knife and use it to carve out the wood (assuming you are on the water). If you can get it on the trailer....just pull the pump...it's easy.

What the hell is a cell phone and why are you using a phone to take Pictures LOL. Sounds like something out of the Jetsons tv show. ok I looked everywhere aaaaaaaaaaaand I do not see a light on my phone!!!

 

[Zeusmotorworks]

Well... I can’t find ANYTHING! Pulled the outer part of the jet unit and not only is there nothing I can see between the screw and housing, but there is also no scoring of any kind that I can detect. Baffled. Suspect there is no warranty left on this 2019 with 140 hrs, but only thing I can think of right now is the splines in the shaft are stripped? Don’t know what else it could be.

 

[Zeusmotorworks]

Pics suck, but…

 

[Zeusmotorworks]

Not even any pitting much less dings in the leading edges of the screw. I never “beach” my boat. Might see 5’ of water on rare occasions and that’s under trolling motor power.

 

[Cobra Jet Steering LLC]

Well if the splines go, it won't go, that was a common issue with sea doo years ago. I would look at the sealant around the intake grate and pump also be sure the clean out plug on that side is sealing good because it is an odd situation and probably has an even odder cause

 

[Inthrustwetrust]

I’d just pull the pump out. It’s pretty quick and easy with a couple long sockets. I had the cavitation followed by a overheat warning last year, turned out to be a snapped drive shaft, probably not your problem, but I would bet it’s something stuck in there you can’t see or the sealant around the intake grates.

 

[FSH 210 Sport]

Thanks, but thought the pumps on the newer little TR-1s where a little different? All still simple enough I'm sure. Bout to go yank it out of the water.

They are different but the concepts are the same. The pumps you have have a replaceable wear ring where the older pumps require the whole section to be replaced, much less expensive to replace the wear ring in the newer pumps.

 

[FSH 210 Sport]

Well... I can’t find ANYTHING! Pulled the outer part of the jet unit and not only is there nothing I can see between the screw and housing, but there is also no scoring of any kind that I can detect. Baffled. Suspect there is no warranty left on this 2019 with 140 hrs, but only thing I can think of right now is the splines in the shaft are stripped? Don’t know what else it could be.

If it was working fine up to 30 mph then the splines are not stripped.

Did you reach up in there and grab the impeller to make sure it is secure on the shaft? The impellers have left hand thread on them so in theory they self tighten while in operation.

There is a wear limit on the gap between the screw and the wear ring, I know the minimum is .014” I’d have to go get my manual for the maximum. The impeller in the pictures looks pristine.

There is a coupler, it’s on the back of the engine where the engine mates with the intermediate bearing assembly but if this was bad it would make a hell of a racket- doubt that is an issue.

It has been my experience so far that cavitation usually happens when you first take off, high impeller speed and low hull speed. So your situation with cavitation occurring at higher speed is interesting to say the least. Assuming the clean out plug is properly seated with no debris in the interface where the removable plugs’ seal and the pump housing come together my best guess is that the sealing ring on the clean out plug might be leaking and or not sealing and air is getting pulled in at higher speed. The rubber sealing ring on the removable plug should be flexible. Have you be treating the plug with silicone spray and removing the plugs when the boat is not in the water?

Do both intake grates look the same as far as sealing goes? Some folks here have had issues with cavitation that was caused by the intake grates not being sealed correctly.

If you are going to pull the pump be sure and keep the Pump at the same level until the drive shaft is clear of the housing, letting it lower allows the drive shaft to push on the rubber hose that can be seen through the inspection hatch in the aft bilge.

 

[Zeusmotorworks]

First off, thank you all for your responses!

Second, this admission of stupidity comes with a poor excuse at the beginning. My FSH 210 is a deluxe. The Bimini is down when the plugs are put in and taken out… meaning the door opens about halfway due to the the undeployed bimini. I reach underneath and I secure the plugs or pull them out whichever. So I’ve been grossly negligent in looking at them. As a proceeding pictures will show, I think my problem has been found. Thank you very much FSH 210 Sport! My Silly ass hardly ever looks at them, because I install and remove them by feel. I’m betting the following pictures show my problem. They are the original ones from the 2019 purchase date ?

 

[Zeusmotorworks]

Anyone have a part number for the rebuild kits for the 210 FSH?