Throttle up and no go...?

[TheYeti]

Well I feel like I shouldn't have touched anything until after testing my first fix. Rebuilt the carbs over winter and changed the pump oil (found what looked to be grease in there, but refilled with oil), then cleaned those rave valves. Took it out today...
Keep in mind I bought it last year at the end of the season. Took it out once and it had a carb issue so just did the rebuild and reset the screws to where they are supposed to be. Starts and idles fine first try now. When i drove it last year it would slowly build up to get to top speed but would plane high and pretty much 'catwalks' through the water. That was then after purchasing it.
Now I take it out today and it idles fine put it in reverse or forward and it will idle in either direction, but throttle up a bit and it does not want to go at all. It will rev up all the way to 7500 or so and then i put the throttle back down to idle. At one point I shut it off for awhile to let my daughter fish and it didn't want to start back up. Eventually it did after trying awhile. Not sure if maybe I shouldn't be sitting in the water not running with these things? It's my first Seadoo boat (first Seadoo anything). So before I introduce the next more obvious problem that happened. What could this be attributed too? Quick google search and the first reply is wear ring If there is a "No go issue" But I don't just want to order that take the family to the lake again and still have an issue. Any thoughts opinions?

 

[POPPS]

I would check the angle of the nozzle,,,seems it is pointed up,,,I would load test the battery,,,I would check compression,,,,and,,,I would pull the seat off and see if you have a lot of water in the hull,,,that will pull the nose up.

 

[TheYeti]

Thank you for the reply. Is there a way to adjust the angle of the nozzle? If so how shpuld it be 'pointed'?. Battery has been on a smart maintainer and had full charge when launched, but will do. I just bought and received a compression tester so also, will do and finally, it is a 1997 Challenger single engine 787. So no need to remove the seat. I did pop the "hood/trunk/hatch and check for water twice though as I saw a small splash of water by me feet. There was none in the hull either time when I checked. I did just clean the rave valves and found one with stripped threads but was working somewhat fine or at least much better before even noticing that. Put back together better than when removed for the time being.

 

[TheYeti]

I just went out there after some more googletubing. Found (what I can't 100% blame on my dad for sure) fishing line around the shaft and also what looks to be a sock or some sort of piece of clothing when inspecting underneath at the intake grate area. Now I need to test again to see if that solves the issue or at least some of it. But the lake is a 35 minute drive away. Jeez. I wish this was something that can be found when running on a hose for a minute.
So another question now.... I jammed my flashlight in the intake grate area and since I have some pieces removed from the transom I took a look amd definately see some light comijg through. Is that a for sure sogn the wesr ring needs replaced? Would that cause a no movement response to any rpm?

Also still open to any thoughts/opinions starting from square one...

 

[wernerml]

The VTS lever sets the vertical angle of the nozzle. If its too high it may have trouble getting on plane, but should still go ~20 mph. Clogged pump is more likely cause.

Another, unlikely cause would be the drive shaft isn't driving the impeller. It would take a pretty significant jam to cause that kind of damage to the shaft splines though so you should have noticed the event when it occurred. At idle friction might make it still go around enough.

Another possibility is cavitation from a poor shaft seal. I was really surprised at the difference replacing my seal last year made on the performance of the boat in getting up on plane. It would plow around at 1/3 speed with the engine running at the limiter at 7200rpm. It might finally get up on plane if it was lightly loaded. I could hear/feel the pump "lose traction" as I throttled up.

 

[TheYeti]

Awesome thank you for the reply and the info. I don't think it would have been the nozzle angle as I put everything back the way it was when I changed the gear oil before winter and the boat would basical go idle, like barely 5 mph with help from the wind would be generous I would think. That again would make me think your 3rd suggestion would fall out for the same reason. Based on your reply I do think your second thought of the impellar being jammed up was the cause. I won't know for sure until I get to test again but when it wouldn't start and scared us (me) for a minute or 2 it almost acted like it was hydrolocked. Then all the sudden wasn't after a try or two and eventually started but not as easily. So I think there was alresdy some fishing line on the shaft, then prpbably some more from my dads "fish" that stole my hook and what probably really did the damage was the 'sock' or rag or whatever I found when I checked underneath the boat last night. My thought is either right before we loaded up at the only test after purchasing and parking it for the winter last year or right as soon as I started it yesterday at the dock for the seasons maiden voyage that I picked up that piece of rag or sock or whatever and the issue started right off the bat. Like I said I know very little about these things but am learning quick and that makes the most sense. It would'nt pick up speed but I thought maybe just idle for awhile being it sat all winter take it easy for a bit but then it would basically only rev up and not change our speed and there was a definate vibration so obviously something wasn't right. My dad wife and daughter went out to let my daughter fish and tedt the boat out for the year so we stayed on the water for abit until we had the no start issue that made me decide to head back towards the dock, being that the lake wasn't real busy and the direction of the cirrent was not faborable for paddling lol
So now I assume I will need to replace the wesr ring regardless but meed to find the proper part # for my 97' single 787 challenger and whay else I'll need to get it swapped out. BUT, if the stuff wrapped up on the impellar shaft was causing the issue I should still be able to use the boat in the mesntime I would assume thought right? Obviously it wont be efficient but still useable?

 

[mikidymac]

If you are getting 7,500 rpm and no forward movement it can only be a pump or driveshaft issue.

First make sure the reverse gate is going down in reverse and all the way up when in forward.

Next check the impeller and wear ring.

 

[wernerml]

If everything looks good on external inspection. you probably won't find out until you pull the pump and drive shaft. You might grab the drive shaft and see if you can rotate it back and forth a bit without the engine moving. That would not be a good sign Not sure how you might try that with the impeller end of the shaft.

 

[TheYeti]

Reverse gate works as normal, checked that. No slack in the shaft when I grab ahold of it and can't rotate it either, but that was an awkward angle and will have to double check the rotation. What would that indicate if while in neutral not running I can turn the blade? I might change the oil again while its apart quick more of a just to check for water thing and put it back together for now to test it eventually while waiting on parts once I figure out what I need. Is there only one wear ring part # for a 1997 challenger w/ a 787? The # I have found looks to be 271000290. Is that correct? Also do I need to order any special tool or other parts along with it?



Edit: Wear ring shows obvious sign (i would guess, I'm a complete rookie here). I'll add some pics shortly. Battery is at 12.5v / 85% charge after sitting a day and doing a compression test. Compression test showed 140psi and 137psi. I think thats ok (?) AND when the boat is sitting here in neutral I can use a pry and move the "prop" fins a little at a time while applying some moderate pressure. I didnt know if it was ok to start it while its taken apart at the back so I only did the compression test and didnt try to actually start it. I need to get some parts on order asap so we can get some uae out of this thing before summer is over

Just an FYI after a couple short reads. When I did my compression test, I had it in neutral and the throttle all the way down. Was I supposed to have the throttle maxed out?

 

[BBird]

You did the compression test correctly, and your results are consistent with compression not being part of your overall issues (They are in the correct range, and more importantly very close to each other.)

 

[TheYeti]

 

[TheYeti]

The last pic was the culprit I cut off the shaft underneath along with the fishing line. Thinking about it maybe its some cheap astro turf of someones bunks from their trailer or something who knows

 

[wernerml]

You are correct your wear ring is messed up but not horrible. Will knock some off the top end but not force slow speed. Some dings on your impeller but again not bad enough.

It doesn't take much debris in the pump path to cause the trouble you were having. Surprisingly small amounts of seaweed can do it.

 

[BBird]

From the close up picture, the wear ring definitely looks frayed on the bottom side. A new wear ring is relatively inexpensive, and is always a good idea. The prop has some chipping on the output side, but doesn’t look to the point where it would cause serious issues. Hard to tell from the pictures if the clearance is too much, but from the fraying I would replace it if it were my ski. The fraying can cause cavitation, and cavitation does weird things.

 

[TheYeti]

Ya those thoughts are exactly what I was thinking. Its hard to get good pictures on the right angle but yes that fraying is pretty ugly in that area. I'm just hoping I can put it back together and take it back out while waiting on parts and not just have to idle around. I don't care if I get full speed and all that, basically just want to hang out with my wife and daughter on the lake. Is the 18mm impeller tool the one I'll need along with the wear ring to do the job?

 

[Jtamaro]

The last pic was the culprit I cut off the shaft underneath along with the fishing line. Thinking about it maybe its some cheap astro turf of someones bunks from their trailer or something who knows

Great you found it, I had similar issues the last time I took out my ski so will check if I possibly have the same issue. Could see anything immediately but I’m thinking I may have to pull off the jet pump to get a better look.

 

[TheYeti]

I just got back from the lake. The boat now drives forward and backward. I mean it definitely needs a wear ring lol. Now that I know what that means. But it acts almost as good as it did when I bought it. Other than the fact that the wear ring got messed the $%#& up when this happened either yesterday or as I docked it after buying and then lake testing with the fam. Still curious when this actually got sucked up. Anyway, After idling along basically and trying different throttles up to full I tried a hole shot, from idle to full bore. The thing stalled out lol. But I didn't have any expectations. So I wasn't shocked at all. I then tried a 0-75% throttle then to full bore and it was fone although it was very underwhelming. That much I expexted after seeing how bad that wesr ring was gouged up. So all in all I was satisfied woth how the day went. I wanted to go out make sure the boat still ran and drive and would actually propel itself(not well obviously) but then again there were 5 of us and if i had to guess we were probably at about 775lbs at least so most likely overweoght for the rsting of the boat(I think, maybe I better check that tag...) Anyway now the part search begins for a quality Wear Ring to order ASAP before summer ends. Or secretly maybe the cheapo one that shows up asap and hopefully works until i find a good one to do the job right..

Thoughts....

 

[TheYeti]

So, Wernerml. When you mentioned the shaft seal, what exactly were you talking about? I'm just curiously considering my next possible problem after replacing this wear ring. The boat runs and drives now but doesn't move super fast (I am assuming the wear ring will fix that) and there is a slight vibration. I will search a wear ring how to soon but just curious what this is in case that doesn't fix the problem fully.

 

[POPPS]

Good wear…or bad wear ring,,.if you throttle up an engine,,lit should. It die out…that is fuel delivery issues,,,pickup,,,fuel selector…carbs,,,

 

[TheYeti]

I redid the carbs(twice), I probably need a new fuel selector then as I can set it on either 3 settings, reserve/off/On and the boat will start and run, so maybe that does something then? Or what? I don't quite understand other than that. OR I need to fine tune the carbs? (If so how) i redid them with junk parts ordered OSD and After the wngine kept flooding it lself I think i just stabbed thru a rubber piece that holds a check valve in place so used am old one and all was goid after that.

 

[TheYeti]

I am wondering now if I can see shipping times (ish) for Priority Mail Express International on OSD website so I can decide if I need to order slmething else in the meantime amd wait for the wear ring from OSD to do work over the fall/winter too or if ill get it quick enough to deal for a week or 2. It's hard to get the good stuff up here on This side of the border quickly...

 

[BBird]

I love the stuff I get from OSD. For a jet pump rebuild kit, you can get that through Amazon as well. Jet Ski Plus has been a very reliable source of parts as well that sells through Amazon if OSD can‘t get it to you quickly.

 

[wernerml]

Yeti,

Inside the boat the drive shaft is attached to the PTO end of the engine crankshaft. From there it passes through the hull and attaches to the impeller in the pump.

In between is the gizmo that keeps water from gushing into the boat around the hole in the hull where the drive shaft exits. Big boats call that the stuffing box, here it is just a rotating seal similar to what is used in washing machines.

Attached to the hull is a black plastic bellows with a carbon bushing on the forward end. On the shaft is a steel bushing that presses against the carbon bushing. The position of the steel bushing is controlled on the drive shaft by a couple of O-rings and a metal C-ring. You can see the c-ring under the front edge of the steel bushing, the O-rings are under the steel bushing.

The steel and carbon can spin against each other without much wear and keeps the water from getting into the boat.

IF the steel bushing is not in proper position or the carbon bushing is worn, or the bellows is limp from age, there will not be sufficient pressure between the two bushings to keep the water from coming into the boat.

During a hole shot, when boat speed is low, but pump speed is high, a strong vacuum can be created in the inlet side of the pump. In this condition the shaft seal can leak air from inside the boat into the inlet side of the jet pump, causing cavitation and reducing pump efficiency. Even to the point where the boat will not get up onto plane. The engine may be running fast but there isn't much umph. Which except one detail is similar to what happens when the RAVE valves aren't working.

Both cavitation due to leaking shaft seal, and RAVE valves not working can result in the boat not getting on plane. It plows along at half speed throwing a big wake and may finally get on plane if the boat is lightly loaded. The DIFFERENCE is that the RPM will jump to 7200 if you have cavitation, or it will hang at ~5500 RPM if the RAVE valves aren't working.

Some people have suggested putting a zip tie around the limp bellows to force it to elongate (not related to ED and Viagra and create more pressure between the two bushings. I had a problem where the C-ring was missing and the steel bushing was too far forward. In older boats sometimes the carbon or steel bushings are just worn out or damaged. A shaft seal rebuild kit isn't all that expensive, but removing the pump and drive shaft in order to replace those parts is time consuming. If you are pulling the pump to replace the wear ring, you might slap in a shaft seal at that time.

Probably more than you wanted to know, but it relates to your potential RAVE issue also. If you had wanted to know what time it was I might have told you how to build a clock

Good Luck

 

[wernerml]

I redid the carbs(twice), I probably need a new fuel selector then as I can set it on either 3 settings, reserve/off/On and the boat will start and run, so maybe that does something then? Or what? I don't quite understand other than that. OR I need to fine tune the carbs? (If so how) i redid them with junk parts ordered OSD and After the wngine kept flooding it lself I think i just stabbed thru a rubber piece that holds a check valve in place so used am old one and all was goid after that.

The fuel selector is pretty simple and easy to clean. Probably the last thing you need to think about when all else fails. Fuel filter may be a more likely issue in that area. The ON vs RESERVE thing is just the pickup point in the tank. Inlet associated with ON will go dry when there is still some fuel. RESERVE dips down to the bottom of the tank and gets all the fuel out. A limp home feature.

 

[TheYeti]

Thanks for the well written description there. Much appreciated. As for the fuel filter I inspected it and all was good I cleaned it amd had actually bought a new one but didn't use it as there was no need. Not sure why I set the fuel selector to off it still runs fine. How do you "clean" that? Juat take it off and blow it out with some cleaner amd call it good?