Easy way to clean debris out of your jet pump (without pulling plugs or going in the water)

[PhatPat]

@Julian - Thank you sir! I notice the very first sentence of this thread, that you started 7.5 years ago, is "First of all the reverse maneuver will not remove something wedged in the impeller". I need to read more carefully - sorry for making you repeat yourself.

@tdonoughue - Fair enough. I appreciate the feedback! And you are absolutely right - those 3 screws are in there really good. I see the shop manual specifies adding loctite to them when you install them, which is probably why. If someone were to remove them, they would be best to use a drill with a hex bit and push very hard so they don't strip the head, or at least use a socket wrench with a hex bit in it. Allen wrench won't cut it. And if you were to strip the head on one of those screws, you will probably snap off the screw extractor trying to get it out, but you still might get it out just enough to get some vice grips on it and turn it the rest of the way. I am speaking hypothetically, of course. ;-)

FWIW, I have taken off both my starboard and port grates before and re-installed them. I have probably over 50 hours on the boat since then and have never noticed any issues - no reduction in top speed and no intake tunnel cavitation (that I know of). I can definitely see the desire to try and smooth out their transition with some caulk or something. That might buy an extra mph...

 

[Julio Dimperio]

I was just thinking that this technique probably won't work with the new electronic throttle system on the 2016 model. I assume that the gates don't move once you kill the engines. What do you think @Julian ?

The jet pump clearing maneuver can be done on boats with BRP ROTAX iST eReverse modules by performing the following:
1- Gain headway in reverse. In rapid succession perform the following
2- Shift to neutral
3- Stop the engine(s) but leave the ignition on
4- Activate eReverse Override on instrument cluster settings page (being on that page already when starting the procedure helps!)
5- Shift to forward and the reverse gate(s) will move up and out of the way allowing water to move backwards through the jet pumps

 

[dhoot]

First of all the reverse maneuver will not remove something wedged in the impeller - it is primarily a weed removal trick. Sticks, bottle caps, frisbees, golf balls, etc....will require manual intervention. But it is always the first step I use in clearing something from the pump. If it fails, then pull the clean out ports (if you have them). Lastly, pull the pump. You really should never mess with the intake grates as this opens up another can of worms (namely intake cavitation).

HOW TO DO IT:

1) Put it in reverse, and get the boat moving backward (faster the better)
2) Kill the engines (pulling the lanyard off is the fastest way)
3) Put the throttles into forward (this allows water to be pushed directly into the exposed jet nozzles and force stuff in the tubes back through the grate, or off the grate).
What I do is grab the lanyard with my left hand, put it in reverse with my right hand, get up some speed, yank the lanyard with my left and instantly put it onto forward with my right.....works 95% of the time. The only time it didn't work for me that I recall was when I sucked up a flexible frisbee...and it was lodged hard in the intake grill.
This works great for weeds, sticks etc.

I just got my 1st Jet boat (2018 Yamaha AR195). Only thing I was concerned about pre-purchase was clogged jets. The steps are easy to follow but is the reason you cut the engine before quickly moving throttle forward to prevent damage to the engine?

 

[Cobra Jet Steering LLC]

NO it allows water to go into the nozzles and out the intake grate the way it came in, for this trick to work you must have NO thrust just backward movement

 

[Beachbummer]

Right, you cut power to stop the impeller from spinning so the wave has a chance to clear the debris while it's loose and not pinned down by the impeller spinning, which it does all the time while the engine is running.

 

[biffdotorg]

Right, you cut power to stop the impeller from spinning so the wave has a chance to clear the debris while it's loose and not pinned down by the impeller spinning, which it does all the time while the engine is running.

Mostly to push out the stuff that is stuffed in the grate, and not even made it into the pump yet. Sort of a backwards flush.

I honestly hardly pull my plugs (unless it's too cold to get in the water) Most of my plugs are in the grate and not the pump itself. So getting in the water and pushing the weeds out with my "monkey toes" is way more effective and quicker than messing with the cleanout plugs.

Of course, there are ways to do this with the cleanouts, but I see no reason in pulling all that through the grate and out the cleanout when the reverse move, or monkey toes can do it much quicker. Coming from a SeaDoo, it was all we had, and I found the cleanouts over rated. (but very nice when the water us under 50 degrees.

 

[Julian]

I just got my 1st Jet boat (2018 Yamaha AR195). Only thing I was concerned about pre-purchase was clogged jets. The steps are easy to follow but is the reason you cut the engine before quickly moving throttle forward to prevent damage to the engine?

You have to cut the power to the engine to allow the water to be forced BACKWARDS through the jet pump and out the intake. Putting the gate(s) in forward means the water flows directly into the nozzle(s) past the impeller and backwards through the intake. You are trying to get reverse flow through the jet pump, so the harder in reverse you go, the more flow you'll have backwards through the pump.

 

[Cobra Jet Steering LLC]

Right, you cut power to stop the impeller from spinning so the wave has a chance to clear the debris while it's loose and not pinned down by the impeller spinning, which it does all the time while the engine is running.

Actually here is how it works , the pump is sucking in through the intake and expelling the water out the nozzle, so first you get moving as fast as possible in reverse then you kill the engines and throw it in forward so the pump is neutral and the water is being forced in the opposite direction through the nozzle and out the intake grate pushing the weeds out with it.
The electronic buckets still work but you have to get it in reverse quickly while the gauges are still on.
I still use that trick and a lot of people on the old obsolete crappy Yamaha jet boaters forum were very grateful when I told them about this because I had a jet boat that did not have clean out plugs back in 2001 and I boat in Tampa Bay with weeds galore and I was not going to jump in the water every time I had to remove weeds from the pump, so after analyzing how the weeds got in I decided to try this and get them to come out .
It works very well I however I designed a special intake grate that blocks most of the weeds and I don't have an issue with weeds like I did 23 years ago. when I was inventing steering for jet boats and other items like EZ locks a few years later at the request of the members of that old site.
I believe there was someone on this site that chewed me out for telling people about my reverse move because he was driving in a lot of mangrove seeds floating on the water so he backed up in shallow water and backed into the mangrove seeds and then nearly ran into another boat and people in the water and got his reverse buckets stuck or something in that realm, so now I don't share the info like I did in the past because I have an old saying you can lead a horse to water but you can not teach either end how to fish!