2010 Evinrude Etec 115 Jet Pump Motor Revs but wont go. Help

Hey guys,


My buddy has a 2010 Evinrude Etec 115 with a jet pump on a 19 foot Lowe, it usually goes about 30-40 mph but the last time it was in the water when we were in Houston it wouldn't open up and it would only do about 10 mph. it seamed like it was okay to a certain rpm and then if you kept easing up on the throttle the engine would rev up but it didn't seam to go any faster. We didn't need to go any faster in the situation we were in but want to get this addressed before hitting the water again. We are not familiar with these jet drives and there are no local marinas in our area. Do any of you have any tips, ideas on what we should look at first? Anything that would cause the power to be lost between the crankshaft and the jet impeller like something that would be slipping?

Does the motor run fine? If yes did it suck junk up in the pump?

Motor runs fine. I'm not gonna say it's never picked up debris but there definitely isn't anything stuck in there. It got worse gradually from what he told me. Does anyone know what kind of clearance there is supposed to be between the impeller and the wear ring or whatever it's called?

1/32" and it looks easy to adjust. Dress the blade with a file if you need too.

https://outboardjets.com/download/Impeller%20Shimming.pdf

Go on "outboard jets" website, "instructions" "impellor shimming", says 1/32" or less.
I would drop the jet intake/foot, remove the tang washer from the impellor shaft, remove the bolt from the impellor shaft and drop the impellor (make sure you don't lose any of the washers on the top and bottom of it, and count the washers that you take off the bottom so you can put it back with the same clearance, if you need to move it up you take a washer off the top and add it to the bottom washers, if too tight you do just the opposite, that's how you shim it up and down for proper clearance). I had mine apart not too long ago, I think it also has a key so the impellor doesn't slip on the shaft, darn---getting old and don't work on them everyday!
In any event, I would drop the intake/foot and liner and check what's going on with the impellor, if you can't find it give Outboard Jets a call.
It's easy to do, just takes a little time, may be as simple as the nut holding the impellor loosened up and too much clearance, or something happened to the key and the impellor is slipping.
Just looked, there is a key!

There are a couple threads on here discussing best techniques for sharpening impellers. Shim to 1/32" like obj suggest. I don't suggest sharpening using their technique I prefer to sharpen what would be the top side of the leading edge of the impeller blades as it is sitting in the intake. Sounds like you guys were probably sucking crap up puttering around wearing down the impeller and liner. With a jet you really want to avoid sucking crap up when I'm coming in to beach my boat I trim up then shut it off to just let it drift into shallows so it doesn't suck sand, dirt, mud, and rocks up. With jets you either run over shallows planed out with the motor opened upped to keep the boat planed out to run over them or you drift over them. Puttering over shallow areas with the intake close to the bottom it will suck crap up wearing down your impeller. Figure out how to take the intake and impeller off, and how to sharpen/shim the impeller at the very least if your going to own a jet boat. That is just nature of the beast kind of like owning a car you should at the very least know how to check tires, air them up, check oil, and top off oil. Sharpening and shimming the impeller is just part of jet boat life.

Sounds like something could be aerating the water going through the pump. It will make it feel like it's "slipping" when it revs and you don't get thrust. Check the intake again for any debris and look close at the impeller to make sure there isn't a damaged edge. Also check the output side of the pump to make sure nothing get stuck in there. Also check the bottom of the boat to see if there is any damage that could cause it to disrupt clean flow into the motor. Are you using it in water that has a lot of weeds? That will cause issues as well. We had a couple of days last summer after a heavy rain that broke a lot of eelgrass loose and it all came floating down the river. I couldn't even get 50 yards upstream from the dock because I kept sucking up the grass/weeds. I gave up and came back 2 days later and everything was fine.

First take it to a lake or river for a test run.

Jets do not like a lot of debris in the water. If you were helping after the hurricane everything was in the water. Anything sucked up to the intake will cause a loss of power. It doesn't matter how much you rev it, if it can't pull water through the intake it will not go anywhere.

Most of the time when you shut it off the debris will float away, so when you check it there is nothing there. Sometimes you will have to clear it with your hand. Think of them as a big vacuum cleaner, anything near will get sucked in or stick to the grates. Any debris the boat is going over is headed for the intake. When it happens the motor usually sounds a little more high pitched and will rev but not feel like it's pushing the boat.

Flood waters are very dangerous to run in for these reasons. You can get in trouble very quick. With all the flooding Houston had there was tons of stuff in the water and I'm sure that was your problem.

Great job helping out. If you test it in the river go up river till you know for sure that was the problem. Let us know how it does so we can help if you still have issues.

Thanks guys for all the great tips, now we gust have to get together and go through some of them until we figure it out. Ill update you guys once we've hit the water.