Has anyone polished or refinished the inside of their jets?

[Bruce]

When reassembling the jet I noticed the portion of the jet inside the hull has a rough surface. Surely this must cause cavitation. I am debating what to do about it. I believe that my boat sat unused in water and accumulated a lot of growth on the pumps before I bought her. The parts external to the hull are very clean and in excellent condition.

I do not want to remove these parts but would consider trying to polish or restore them in place.



Additionally this edge is protruding.

 

[Wayloncle]

Im sure it would help to clean that up, I'm interested in reading what people say to use.

 

[swatski]

@Bruce In general, do not expect noticeable improvement in performance from cleaning all the inner surfaces. I don't think there are any reliable accounts of substantial performance improvement due to surface preparation/smoothing out. I have read about guys blueprinting the inner pump surfaces to the point of near perfection and gaining.... 0 mph!
I find it somewhat surprising, but so are so many other things about these pumps.
Missing sealant on the other hand, leading to sucking air from outside the pump - is always associated with cavitation and poor performance. It is not always easy to identify, such as around the transom plate. I guess cleaning may be very helpful in that regard - finding potential trouble spots. But cleaning surfaces per se will not likely help much.

This is of course just MHO.

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[DCB-270]

I polished the pumps on my Exciter trying to gain every MPH I could get out of iit and got 0 like mentioned earlier. Still if they have any kind of build up I would clean them.

 

[Speedling]

I polished my pumps up!
Lots of bumps and knobbies and burrs. Sharpened veins ever so slightly but left with a slight roundness to it. All casting marks removed.
Speed improvement probably not. Efficiency could have improved slightly though from not going around the big stuff. I didn't mirror polish either. A little tumbling can be good however with the water being pressured at the bowl i have thought about polishing that up good.

Fyi, i have had a little experience port and polishing heads for my mistang which turned out impressive results. Stock E7 heads put me about .3 seconds faster in the quarter. Steel heads so it took forever though!
These aluminum pumps can be eaten through very quickly with power tools like dremels. Be very careful and start with the big stuff.

 

[scokill]

Cavitation is air mixing with water, and it looks like those are exit points, not entrance....could be wrong, but either way I can't imagine it matters.

 

[buckbuck]

Dressed mine up with a Dremel. Made me feel better but I don't recall any performance improvement.