Huge Power Loss

[AboveTheBest]

Ugghh

 

[Robconn]

How many hour on boat?

 

[Robconn]

Sound like it’s not timing chain. So hopefully won’t be expensive or time consuming to resolve.

 

[AboveTheBest]

96, but about 60 on new engine.

The previous owner forgot the plugs once and had to have the original engine replaced, luckily insurance covered it.

 

[boudin]

Do the pump bearings feel smooth--the shaft/impeller are smooth when turning and you can't wriggle the impeller side to side, or back and forth? Were the bearings the shop (or you) put on OEM or aftermarket?

What did the driveshaft look like where it meets the bearings? Many times with a bearing failure it will wear an indention in the driveshaft, ruining it.

The wear ring looks normal. I'm thinking the rust came from a seal failure last time? What does the clearance look like when the pump is in?

What do the splines on the drive shaft look like?

Pics will help.

-Greg

 

[AboveTheBest]

@boudin
The bearings are WSM and everything in the pump turns with no binding.

I just removed the wear ring and assembled mocked it up with the pump on the bench to check if the impeller was binding, it was not.

The splines look fine, and the shaft doesn't appear to be be bent.
After reading on Greenhuok and other PWC forums I'm wondering if my intermediate shaft isn't ruined now.

 

[boudin]

You'll feel a bent driveshaft--it will shake/vibrate. Very hard to tell unless you remove the shaft and place it on a straight edge.

Doubtful the intermediate shaft is bad unless it's leaking, but anything is possible. The intermediate shaft is short, and I doubt a wriggling driveshaft caused by bad pump bearings (like yours were) would cause any issues with the intermediate bearings, especially since the intermediate shaft is a bit flexible as the whole thing is in a rubber sleeve. But again, anything is possible. The only way to check is to remove the intermediate housing and check, which of course means unbolting the motor and pushing it forward.

 

[AboveTheBest]

I had a shop do the bearings and they told me that the shaft was eaten up a little but they were able to save it.

I’m thinking that may not have actually been the case, but it seems to spin freely when I have it on the bench so I don’t know what to think.

 

[swatski]

Went out yesterday and had about 5 minutes of pure boating bliss before problems started again.
When I first backed it off the trailer I heard a “clunk” as I applied power, but it wasn’t followed by any other noises or problems.

It seemed like it was a bit underpowered and when I took off across the lake it started losing power and bogging down the engine.

Fast forward through 30 minutes of me with a ski rope tied around my chest swimming the boat back to the ramp...

I got it home and took the pump out this morning and took the cone off to make sure the noise I heard wasn’t a bearing exploding or impeller snapping. I changed the oil and pump new plugs in (just because I had them), and ran the boat with the pump removed for 5-minutes. No power loss or any other indications, which means the problem is somewhere outside the boat (thank God).

The impeller housing(s) are both deeply grooves by the impeller, and I’m assuming this is the cause of my new problem (pic below).

I’m getting ready to order the two housings and maybe even a new impeller, but I’m afraid the problem may be with an improperly aligned intermediate bearing. If I replace the housings and something is skewed it could ruin the new parts as well.


Anybody have any suggestions?

View attachment 80507

Sorry you are having issues!

I had to look up the 190 pump, it has two impeller housing segments, which is confusing, the 240s have only the wear ring. What I don't understand in your pic is what's going on with part #3 segment - it looks to me like it is being ground up (by impeller?)


What is this crease (blue arrow) in segment #3 (housing impeller 2)?
Are those rusty spots due to wearing liner of stainless steel being ruined (red arrows)?


And then the front (or back really) of the wear ring shows NO WEAR...
It's as if your shaft got shorter? and the impeller is spinning inside the part #3 segment (housing), while it should be contained in the wear ring segment...

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[boudin]

The housing closest to the transom is a 2" spacer and common to HO WaveRunners as far back as the GP1300R.

I've never really seen a good explanation of why the spacer is there, but my guess is to reduce cavitation. It requires 2" longer wear ring to transom bolts.

-Greg

 

[AboveTheBest]

Good observation on the second wear ring @swatski this had me puzzled as well.
Even more so when I assembled all the pieces on my bench and thenimpeller didn't get anywhere near the second housing.

The rust is likely from when the pump bearings came apart, and unfortunately I don't know how long the scratches (which are quite deep) appeared in the second housing. How in the heck could the impeller even get that far back...?

 

[boudin]

There you go, the spacer is there to help reduce cavitation.

http://www.greenhulk.net/forums/showthread.php?t=273684

-Greg

 

[AboveTheBest]

I’m contemplating putting it all back together and firing it up in the driveway to see if I can find where it’s binding up, at the risk of further damaging whatever is broken.

 

[boudin]

To make sure everything is aligned, don't tighten the (5) wear ring/spacer/transom bolts before (4) tightening nozzle/impeller duct/wear ring bolts. This allows some wriggle room for the proper alignment of the impeller duct and wear ring.

If you left the wear ring bolted to the transom (like your pic above), then you should be fine.

But I'm still thinking you should check your impeller shaft to make sure there is no side-to-side play. I would clamp the impeller duct into a vice, and then make sure you have no side-to-side movement of the shaft. When the shop said they saw some wear to the shaft, it would be good to know more details.

-Greg

 

[AboveTheBest]

After the bearings went out I took the wear ring off too while trying to get the pump out of the boat (turns out the shaft splines were stuck).

When I put it all back together I tightened the wear ring down first and then the pump/nozzle. Maybe that didn’t allow everything to get properly aligned.

I’ll see if I can find a vice big enough for the test you suggested.

 

[swatski]

Do you have all the dowel pins? I don't think that is an issue, just easy to lose those.

I do not know the pump bearing anatomy good enough (inside the stators segment) - but is it possible the bearing assembly was moved backwards (fore) to accomodate the shaft that was, perhaps, shortened (in order to remove stripped splines at the end)?
Total speculation on my part, needless to say.

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[AboveTheBest]

I do have all the dowels, and I even ordered some spairs

The shaft is still the correct length and I don’t even see how it’s possible for the impeller to have gotten that far forward since it’s held in place by the bearings/nut inside the pump.

When the bearings were trashed the pump actually slid backwards during my vigorous removal efforts. Maybe the gouges happened when I was wiggling it back and forth...

 

[swatski]

Well, with the engine running fine with the pump off, that really narrows it down, doesn't it?

It has got to be the impeller binding (?) inside the wear ring/other impeller housing segment... If the shaft is strait and original length - new wearing and the other part seems like the way to go...
Effing OEM wear ring is so expensive!

I have in the past used a cheaper aftermarket with delrin/plastic inserts. I actually like those as they are much quieter. I don't knwo if that is something you would consider, just thinking out loud...

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[boudin]

I have a drive shaft that was subject to badly damaged bearings and it wore an indention in the shaft and is now unusable even with new bearings. That’s why I’m asking.

 

[swatski]

@AboveTheBest what's the gap between the trailing edges of the impeller and the stator segment - after rebuilt? It should be sitting just a couple mm apart, I think.


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