It Was Bound to Happen with a Warning

[David Martin]

Well guy its "happened" been jet boating around 9 months and just clogged my first jet!!!!! I will also give a warning about clogs and YES going to pimp slap Yamaha engineers a little. First the clog....... the sea weed in my cannel just off Charlette Harbor these little buggers are about 8 inches long and look like a snap pea about the thickness of your finger and they flote up right you can only see the little tip and most are below the water service. I felt the forward thrust loose about 30% the starboard engine lost 200rmp and the port remained at 1600rpm. I let her go for about 30 seconds pulled her into neutral and drifted a little seeing if she would clear. (No luck) hear is the WARNING and you guys probable know it, but us Jet newbies not having a true neutral it can lead you into trouble.

As I goosed the motors with a quick blip of the throttles to clear the jets the debris jammed the gates open and will not allow you to throttle back to first Idle indent........YOU CAN SEE THE PROBLEM, stuck at idle jammed gates full open and the speed of the 3000rmp. Could not drop into neutral and move to reverse. Could have been tragic in close quarters like a busy fuel dock ect...... within a second I shut the keys off......my wife said she was glad I was driving because she said she would not have turned keys off. So their you have it the Newbie learned today do not use throttles to clear jets Period just don't do it. Shut it down and clear it out.

Sorry Yamaha I'm going to call you out for the next one put temp and oil pressure gages on these boats so a quick glance I can diagnose what going on...............as I hit the debris field and felt my boat loose forward momentum I quickly look at my rpm gages(Analog) and determined(quickly) my Starboard engine was down 200 rpm and the next quick glance was to the TEMPETURE GAGUE I INSTALLED and I watched my temp rise 30 degrees on port engine in about 30 seconds so I went from neutral to 3000rpm blip to clear(fatal mistake on my part) I own that.................but Yamaha you own the stupidly of not giving owners gages to take care of PROBLEMS long before the computers go off. I never came close to over heat / limp mode or even close to hurting and seal/gasket/rubber hose ect................... RANT OFF!

Next project OIL pressure Gauge sorry but it should have been on the dash from the start Yamaha.

 

[Julian]

I am struggling to understand how throttling up caused your gates to jamb....can you explain further?

Typically the only way to get gates stuck is to throttle up when very shallow and in reverse....causing small pebbles to jamb the gates.

I'm curious to understand how your gates jambed....

 

[David Martin]

As soon as I passed through the debris I lost the ability to go in neutral from (forward second indent) it would move back and forth between first and second indent but not up to neutral.....I moved it back and forth between first indent to second indent several times and it finally went into neutral.

Now at this point I tried to go back in forward(no go throttles would not move from neutral) I had lost control of the boat at the worst place in the cannel 30 ft wide cannel concrete on one side Mangrove's on the other an incoming tide through a open passage lock between to cannels......this concrete channel has tens of thousands of gal of water moving through it ever min during a rising or falling tide so it is one of the worst swirling currents.....a jet boat nightmare for sure. The throttles moved into reverse(first and second indent) so that when I made fatal MISTAKE I blipped the throttles thinking it would clear the sea weed pods............bad move throttles leavers stuck down......that when I hit the keys to off I drifted backwards into the mangroves (soft landing)

Cleared out the debris from the impeller through clean out plugs then I cleaned out the gates hanging off the back. The gates had the long pods sticking out of ever nook and cranny all over the gates and the lateral side thruster were pack full with the pod hanging out the lateral thruster ports jamming the gates tight. The pods were stuck heavy around the cone are as well. All was well after a good clean out. What a PIA.

 

[David Martin]

Now hear is HIND SIGHT at its best.........WHAT I should have done as I passed through the debris..... I felt the forward thrust loss and noticed my starboard engine lost 200 rpm and the temp was rising in that engine. I should have just shut down that starboard engine AND should have UNLOCKED my throttle locks (you know the one keeping throttles levers together) and carried on with the port engine, but hay that how that darn hind sight go's.

 

[Acard7]

Now hear is HIND SIGHT at its best.........WHAT I should have done as I passed through the debris..... I felt the forward thrust loss and noticed my starboard engine lost 200 rpm and the temp was rising in that engine. I should have just shut down that starboard engine AND should have UNLOCKED my throttle locks (you know the one keeping throttles levers together) and carried on with the port engine, but hay that how that darn hind sight go's.

As soon as I have any vibration/cavitation with power loss I shut down immediately and head to the back to clean the pump. I’ve never had luck with throttling up to clear the jet pump, ofcourse I have dealt with wood chips and sticks not seaweed or vegetation! Obviously if you can’t get it all cleaned out through the clean outs you’ll just have to limp home on one engine and do damage control on a lift or out of the water, but I’m glad you had it figured out! I’ll be interested to see your oil pressure gauge when you get it done.

 

[Cobra Jet Steering LLC]

use the reverse move, do a search for it, tons of posts also while you are doing searches look up limp mode is NOT safe mode. And how to run on just 1 engine being new to jet boats this could save you a lot of serious problems in the future.

 

[Acard7]

use the reverse move, do a search for it, tons of posts also while you are doing searches look up limp mode is NOT safe mode. And how to run on just 1 engine being new to jet boats this could save you a lot of serious problems in the future.

I’ve tried the reverse trick a few times without success. Since our boats don’t have a true reverse I believe this is why it’s not always successful.. Thankfully I’ve been able to get anything out that has gotten stuck. Definitely agree people need to know how to get home on one engine if they are new to jet boats.

 

[AZMark]

use the reverse move, do a search for it, tons of posts also while you are doing searches look up limp mode is NOT safe mode. And how to run on just 1 engine being new to jet boats this could save you a lot of serious problems in the future.

What do you mean by limp mode is not safe mode? You just mean you can still do damage?

 

[Cobra Jet Steering LLC]

no the reverse move look it up it has been working for me for 20 years your post tells me you don't know what it is so do a search it will save you a lot of problems.

 

[Cobra Jet Steering LLC]

What do you mean by limp mode is not safe mode? You just mean you can still do damage?

HELL YES DESTROY THE ENGINE

 

[Cobra Jet Steering LLC]

Every year I call it the class of whatever year it is now we are changing from the class of 2021 to the class of 2022 this is normal but learn to use the search mode and you will find all sorts of very valuable info.

 

[Acard7]

Just so everyone is aware, when I say “limp back home on one engine” I mean use the good engine at idle/no wake speed to get home and turn the other one off with bucket in forward detent. I have clamps in my boat to clamp off the water line as well. I need to just get the valve installed on both that’s in a thread somewhere in here.

 

[Cobra Jet Steering LLC]

not what I was referring to limp mode is what your computer will do if there is a serious issue like low oil or overheating an engine, if you continue on without addressing the problem you will probably cause serious damage .

 

[David Martin]

I have a set of plastic clamps on board for anything above idle .............I read about the clamps from someone out hear on this site....Good stuff.

 

[Julian]

I have a set of plastic clamps on board for anything above idle .............I read about the clamps from someone out hear on this site....Good stuff.

Wow ....sounds like you had some seriously clogged pumps. I wonder if the lateral vectors contributed to increasing the clog factor? I can imagine weeds getting stuck in them and causing further clogging.

If I am ever forced to boat through having weeds, I shut one engine off and run though the weeds. If that engine clogs i shut it down and switch to the other, if that clogs I first drop and anchor, THEN deal with the clean out. Usually I avoid such bad weeds.

As Cobrasteering says....learn the reverse maneuver. Its in the FAQ.