Throttle Issues on my 2005 3d RFI

[ThreeD]

SO, I'm having throttle issues after about an hour on the water. For no good reason, after an hour, you can open the throttle all the way, but I get minimal RPM's. Had it in a few times for service, but they can't find anything blatantly wrong. I've read a few other posts in here that seem to suggest that this might be a throttle sensor, compression, or fuel/oil mixture problem. I'm really at a loss for this, as I do not have a mechanics touch. any suggestions as to where to start are welcomed. Thanks!

 

[Ibanez540r]

The whole "one hour later" sounds kind of odd. Are you sure it's just not coincidental that about that long after riding your sucking seaweed, etc. into the jet and not knowing it?

Again if not the hour issue, I'd start with fresh spark plugs, make sure fresh fuel, check wear ring...

 

[ThreeD]

I'm pretty sure nothing is sucked up. When I did take it in to be serviced last, they said I needed a new wear ring...would this cause the throttle to go to minimum after an hour of riding though? Seems like when I pull it out of the water on the trailer and crank the the throttle, it spins up just fine. When the throttle does die down on the water and I get the back end out of the water a bit on some wake, the prop and rpms spin up again until it is submerged again....I have no Idea what this could be. Anyone know If this model has a limp home mode? I've been doing some reading and it seems like maybe a throttle (position) sensor is bad? lemme know what you guys think.

 

[ThreeD]

Seems like i've had this problem ever since I rolled it and it was upside down with the engine running for about 15 seconds before it died. Possible cause?

 

[ThreeD]

Anyone else that is knowledgable on this stuff reading? I wanna start working on this problem but have no leads. If compression was a problem, would it take an hour or so to become detrimental to the way the ski runs? HALP!

 

[Ibanez540r]

If it was the wear ring, it would be constant, higher RPM & slower speed.

When coming out of a wake, it is normal to hear the engine rev. A ski is propelled by water forced through the jet, when you come out of the water or "porpoise", the jet is not fed water, less resistance on the impeller, resulting in a REV with no accel.

If it really is an hour everytime, it has to be electrical. Anything else would be mechanical. But since you flipped it, I would definetly pull the plugs, turn it over, and put new in. Also if the wear ring needs replaced, replace it. You'll see a big difference in power, but not the answer to the "hour" power loss.

 

[Ibanez540r]

Oh.... another possibility... your plastic exhaust couplings have melted like many others and are getting an exhaust leak in the bilge, eventually choking out the motor.

 

[ThreeD]

YES! I talked to my car mechanic friend today and he definetly thinks it is exhaust related. I will check to see if anything is melted when I get in there. He also seemed to think that something is either leaking or blocking the exhaust(resin?) If that is the case, he recommended that I remove the exhaust and heat the crap out of it until the resin burns off. If there is something blocking it, I'm sure I will see it then. Thanks for the help Ibanez, I will let you know what it is when I get in there. Keep throwing ideas out there, they have definetly helped!

 

[D 5UPE]

3d's do have a limp mode like all the rest. If the mpem recognises a fault it will shut down to limp you back to shore.
Things to check are:
plugs condition colour. If black your probably not useing the recomended oil.
If one or both plugs looked washed out your getting water in your cylinder.
Maybe you rolled it and sucked it in. Or worse you have a cracked cylinder waterway.
Your engine will shut down and limp if your plug insulator cracks. I found some of my plugs have gone this way.
Over heating will shut her down if the wearring is badly worn or waterway blocked.
Drain your tank completly if it been upside down running. Mine had a costly fuel regulator due to this. As the tank breathers are rubbish and will draw water in under pressure.
Tighten your banjo/ jubilee or trident clips"(USA or European ) regulerly on
your exhuast.
Typed from my mobile and still horizontal in bed.
So typing errors in there lol.
David.

 

[davebboys]

I had the same problem with the jet ski losing power after an hour, we took the back floor cover off and found the plastic exhaust was melted causing the exhaust fumes to choke the engine.

Have just found that there is a hole in the bottom of the cast aluminium exhaust causing a loss of cooling water to the last sections of rubber/plastic.

 

[ThreeD]

Good to hear daveb(not in the sense that it happened to you, but this helps me out alot)! The engine compartment reaks of gas fumes. Haven't got a chance to take off the rear floor plate, but I'm willing to be that your issue is the same as mine. I'll let you guys know what exactly it is when i get in there. Thanks again! you guys ROCK!

 

[ThreeD]

Opened her up last night and didn't see anything glaringly wrong under the floor plate. When u guys are saying that the plastic exhaust was melted, what exactly melted? All my hoses and resonators look good and all styrofoam back there looks brand new. If there was an exhaust leak, wouldn't there be some kind of residue built up in here? Probably going to take out the muffler and make sure there are no holes in the underside of it, but it looks relatively clean back here.

 

[ThreeD]

Took off T fitting and checked hose to the muffler and to the resonator(upper single one). Looked into the muffler and everything "looked" ok. There was some water in the bottom of it, but no indication of rust. Resonator pipes look brand spankin new and no melting. The couplings on all 3 openings of the T pipe look normal and not melted. I'm at a loss now...not sure what the issue is. Could the RAVE valve be getting stuck closed? Others have suggested a bad rectifier. Do my symptoms indicate a problem with the rectifier. Help guys!

 

[magical]

i would check your raves first its an easy fix if they just need a good clean before you go and spend money on parts

 

[ThreeD]

Just checked the fuel filter ( what a pain to get out! ) and it looks pretty dingy...It was a dark orange color. Not sure if it needs to be replaced, but since i have it out already, I'm changing it. Going to take apart the rave valves as soon as my gaskets arrive. Its been brought to my attention that it could be a throttle cable/line or throttle sensor. Anyone have any experience with this?

 

[ThreeD]

Ok, changed fuel filter! I opened up the Rave valves to find the valves covered in mold...I'm think i've found the issue needless to say. I guess my one question is can i clean these or do i need to drop 40 bucks for 2 new ones?

 

[jwalts27]

you can clean them. Use some decarbonizer spray and an old toothbrush and some fine grit sandpaper. Clean them really good and whatever you do dont use a screwdriver or heavy scraper and gouge them.

 

[ThreeD]

Alright, Cleaned them out! To be honest, I was a little disappointed in how clean they were. I was hoping to pin the needle on the head in identifying exactly what is wrong. The valves themselves looked good, a little carbon build up on the guillotine edge, but nothing major. There was a lot of oil/goo in the bellows though, which I cleaned out as well and could still be the culprit. I didn't change the o-rings on the valve stem as they looked brand spankin new.
I'm putting the back half of the exhaust back on and finishing up the rave's tonight. Thursday is water test time!

If the problem persists, I've narrowed the issue down to either electronic or throttle. These are the only things left i can think of...Oh and possibly the fuel pump

 

[ThreeD]

Fired it up last night and it sounded AWESOME! Guess the real test comes today when I take it for a dip in the lake. Crosss your fingers and lets hope i get more than an hour on her!

 

[ThreeD]

First off, thanks to everyone who posted in here and gave great suggestions. I dropped her in the lake yesterday and she ran for 4 1/2 hours problem free! She ran like a champ and had a screamin solid day at the lake. It must have either been the gunk in the bellows of the Rave valves, the fuel filter, or the seal from the rubber exhaust tube to the main resonator, as these were the only things I touched. I'm just glad it is finally runnin like a champ again. Thanks again guys!