Low budget fix for Yamaha pump liner swelling issue

[Cobra Jet Steering LLC]

When my timing chain hatched my ski was in the shop for 2 months before it was finally fixed.
Upon it's return I noticed a bad ringing in the pump when running on the trailer so I knew the liner had swelled up and it was hitting the impeller. So I replaced the pump section with a different type similar to what sea doo has and this has been just great with no noises in the pump and no problems in any way.
It has replaceable liners so you don't need to keep buying the entire housing when a liner goes bad.
In any event I was messing around the shop today and I decided to play with the pump liner section that I had removed and replaced .
Everyone knows that the issue is caused by dissimilar metals corroding between the stainless liner and the aluminum housing. Since there is no place for the expansion to get out , it eventually pushes up on sections of the liner and causes it to contact the impeller, this can even lock up the pump as it started to do to me. So decided to experiment with releasing the pressure and dissolving the aluminum oxide in between the two parts. Well I was throwing it away so no big deal if it gets ruined.
I found the spot quite easily and using a 1/4 inch bit I drilled a hole in the aluminum housing directly behind the problem section of the liner, taking care not to drill into the liner itself.
I then inserted a short piece of plastic tubing in the hole and placed a few drops of muriatic acid in the tube. Outdoors obviously! Then I watched the black gunk bubble out of the tube, when it stopped I cleaned the opening with water and decided to use a small ballpeen hammer on the raised section of the liner.
In retrospect I should have made a thin piece of metal to shield the liner from any small marks caused by the hammer but I was not concerned about that since it was just an experiment.
After working the high spot down where it belonged and sanding the area a bit I honestly believe this would save the piece and allow for any further corrosion to be released via the hole, it would not have any way of building up sufficient pressure to bulge the liner again. In any event if you own a older ski and you have more time than money you could try this remedy and see if it saves you some cash.

 

[KXCam22]

Thats a smart fix!! Not hard to do as well. Cam.

 

[Geoff Cooper]

That sounds interesting.

 

[Scottintexas]

added to the FAQ under pump wear ring

 

[Cobra Jet Steering LLC]

I just hit 500 hours on my ski that hatched the timing chain last year and interestingly 500 on the one that did not hatch the chain go figure! I have noticed since changing to the plastic liners the one with the new chain was getting a bit slower but not cavitating, however It did feel like the pump was just not putting out the same thrust as the other one.
I braved the heat today and puller the pump apart on the one that was feeling a bit weak. I quickly discovered the plastic liner was gouged pretty badly Now replacing a liner is only a few dollars but I really wanted to try this fix just to see how well it works.
I have a pile of original pump sections with bad S S liners. I took one and fixed the high spots in the liner as described previously, I ran a flapper disc over the sections that I fixed, then I placed the liner section on the pump and turned the drive shaft by hand looking for contact . I could not find any contact between the impeller and the liner so I put it all back together and started the engine, still no noise, so I plan on trying it out this week just for the hell of it . This pump was so swollen that it was dragging on the starter when you first started it up, now it is very quite. So I plan on monitoring it to see how long it works before it starts making noises again.

 

[Cobra Jet Steering LLC]

Ran it all day and it works just fine, now we see how long it lasts since the plastic wear ring lasted about 10 months and about 150 hours of use.

 

[Cobra Jet Steering LLC]

Funny thing is now at 871 hours I still have the same original impeller and the plastic liners work great I now purchased 2- 2021 models and thought Yamaha did away with the stainless steel liners but looking in the pumps I see stainless steel liners.
I added zinc anodes to the pump housings just to reduce the corrosion since all I run in is salt water The engine still has the original timing chain as well so I wonder how one hatched and one did not.

 

[FSH 210 Sport]

Thanks for following up on your last post from three years ago!

I had looked at the impeller change threads and looked at the parts fische. It looks like the sleeve is replaceable now ? Part #2.