95 Waverunner 3gp, feels like it's in limp mode

[felix5oh]

701 had no spark. Bought an ebay stator and double checked that it was in the correct position and now it starts right up but won't Rev up.
Ran it on the flush and i can see fuel flow through the Venturi. Feels like limp mode but thermal switch is disconnected. It goes right back to a perfect idle.
I had a spare ignition coil and a spare CDI and same issue.

This ski ran great before it lost spark. I checked the fuel delivery and return and check valve and everything looks good. Don't think it's fuel related.
I removed the flywheel again and nothing looks out of place and charge coil and pulse coil looks like they are in the correct position. I can't explain why it wouldn't throttle up and returns to a perfect idle. The no spark problem was the stator. I don't know why it seems like it's being limited but the pink wire is already off

 

[E350]

You know more about this stuff than I do, but the symptoms you are describing turned out to be a partly clogged fuel filter screen in the carb. I have a photo of it around this website somewhere. Basically, a partly clogged screen will let enough fuel through to idle, but not enough to wide open throttle. I also replaced the fuel tank check valve at the same time to rule out a fuel tank vacuum.

Do you have a primer? If so, will it rev past idle when you pump the primer when it is idling?

Also, we have a 1996 Wave Venture 700. I don't think it has a "limp mode." So, if you don't mind, what do you mean by limp mode?

 

[thudd3rski]

there is a post about a 94 wr3 showing the same symptoms.

1994 Yamaha Waverunner III won't rev up much past idle

Hi everyone, I just recently bought an old Yamaha waverunner that had a new engine installed about 12 years ago. It's sat the last 7 years, and was started once a year but not run. It starts and idles perfectly, but in or out of the water if you rev the engine it revs just a little and no more...

greenhulk.net

in addition to the fuel suggestions, there was also a suggestion about the waterbox (baffle breaking loose and choking the exhaust)

you said the pink wire is disconnected (removed tempo sensor)...cant remember if it is a male or female connector, but may want to verify it isnt grounding on something in the ebox

 

[felix5oh]

The ski had a great summer last year. New pistons and seals. New wear ring. Fuel return line is full of fuel, but I will check the filter. It ran fine wide open until it lost spark and now this problem. Tank vent check valve is working.
(The pink wire goes to the over temperature sensor that when grounded the CDI only revs to 3000 RPM so you can get to shore. The e-box is open and pink wire is not touching anything.)

 

[WFO Speedracer]

Rig up a piece of PVC pipe to bypass the waterbox and run the ski I have had a couple of these with bad waterboxes that gave me a run for my money.

 

[felix5oh]

Rig up a piece of PVC pipe to bypass the waterbox and run the ski I have had a couple of these with bad waterboxes that gave me a run for my money.

I tried that.
Could something in the stock exhaust come apart or break to cause this problem ?
I've never worked on stock exhaust

 

[WFO Speedracer]

nothing I am aware of, have you checked or replaced the reeds yet, I have several sets of Yamaha reeds that looked good bite me in the ass, fire it up. hold your hand close to the carb and rev it up, if you feel anything coming back up through the carb the reeds are bad, they will usually rev out of the water with bad reeds under a load in the water its a no go situation. is it possible it backfired and took out a reed when it lost spark ?

 

[felix5oh]

I was thinking reeds but wouldn't that affect idle also? It returned to a perfect idle every time. I can see fuel flowing out of the HS Venturi and a cloud of fuel does come way outside of the opening.
I wasn't riding when it happened. They ran it wide open for a while and then idled a bit to an island. Hit the stop button. Went to start and never came back. Replace stator and now this.
Thank you for your time Bro.

 

[smoofers]

I was thinking reeds but wouldn't that affect idle also? It returned to a perfect idle every time. I can see fuel flowing out of the HS Venturi and a cloud of fuel does come way outside of the opening.
I wasn't riding when it happened. They ran it wide open for a while and then idled a bit to an island. Hit the stop button. Went to start and never came back. Replace stator and now this.
Thank you for your time Bro.

I had GP1200r with bad reeds. It would idle beautifully but wouldn't rev past 1/4 throttle. I would definitely check the reeds.

 

[WFO Speedracer]

Believe it or not ,no it will not affect the idle because the throttle butterfly is basically closed at idle speed , look at the butterfly position next time you remove the carb , it is barely cracked open so reversion cannot happen, it can't get past the throttle butterfly at idle., anything past 1/8 throttle or so and look out .I also had a couple of XL1200's run me through the ringer both times it was bad reeds, as in Smoofers case it wouldn't get above 1/4 throttle and ran like a dead dog. Polaris watercraft were notorious for breaking reeds off.

 

[felix5oh]

Reeds look great.
I'm going to try another stator and rebuild the exhaust gaskets. Stay tuned

 

[WFO Speedracer]

If you didn't check the reeds the way I said you have done nothing, in both XL1200's the reeds looked great, there were no chips or missing petals, no apparent hook in the reeds, no place that they looked like they were not sealing, there was absolutely nothing that looked out of the ordinary at all, on both skis the reeds were bad. I replaced the reeds and the skis were fixed.

 

[felix5oh]

If you didn't check the reeds the way I said you have done nothing, in both XL1200's the reeds looked great, there were no chips or missing petals, no apparent hook in the reeds, no place that they looked like they were not sealing, there was absolutely nothing that looked out of the ordinary at all, on both skis the reeds were bad. I replaced the reeds and the skis were fixed.

Still doing it with the other stator!!!
I saw your test recommendations and I don't have to hold my hand over the carb. I can see it . A cloud of fuel stacked passed the opening while I was revving and it returned to a perfect idle every time.

 

[WFO Speedracer]

I have seen them so bad that it actually hit you in the face when you revved the engine, no way it rev when pressure blowing back through the carb cancels out the carb signal drawing fuel and air in. Like I said the reeds are not really in play at idle speed

 

[felix5oh]

New reeds, still doing the same thing!!!!
I'm out of ideas.

 

[DylanS]

New reeds, still doing the same thing!!!!
I'm out of ideas.

Can you post a video of it ?
Have you torn down your carbs? Have you tried spraying fuel in with throttle cracked to rule fuel delivery out 1000%?

 

[felix5oh]

I will post a video later when I get back home. I went through the carbs. I will try the pouring of the fuel while running but it just sounds like ignition fail or miss. Kinda like when it's in limp mode.

 

[WFO Speedracer]

Ok one more thing before you go any farther , this is something that I have run across only on Yamahas, the spark plug boots go bad, from what I remember when you cut them open they have a resistor inside the cap that looks like a small piece of carbon, this is on the older spark plug boots that are black and look like multiple pieces put together, the newer red style caps I have not seen issues with, anyway high resistance in the caps make the ignition missfire, I have solved several mystery ignition issues by cutting the wires off and installing NGK style spark plug caps or MSD spark plug caps

Advance Auto Parts - Down for Maintenance

https://www.amazon.com/MSD-3311-Spa...vnetw=g&hvrand=15347397391754887708&hvpone=&h

Green Rubber Waterproof Moped Spark Plug Boot

Green rubber waterproof spark plug boot for 7mm spark plug wire.

www.lucky2strokes.com

 

[felix5oh]

Are you using Chinese Knock-Off Stators?

The only good Stator Brand choice is OEM Yamaha.

Yeah expensive, but worth every Penny. Or find a good used OEM Stator...

Ok one more thing before you go any farther , this is something that I have run across only on Yamahas, the spark plug boots go bad, from what I remember when you cut them open they have a resistor inside the cap that looks like a small piece of carbon, this is on the older spark plug boots that are black and look like multiple pieces put together, the newer red style caps I have not seen issues with, anyway high resistance in the caps make the ignition missfire, I have solved several mystery ignition issues by cutting the wires off and installing NGK style spark plug caps or MSD spark plug caps

Advance Auto Parts - Down for Maintenance

https://www.amazon.com/MSD-3311-Spa...vnetw=g&hvrand=15347397391754887708&hvpone=&h

Green Rubber Waterproof Moped Spark Plug Boot

Green rubber waterproof spark plug boot for 7mm spark plug wire.

www.lucky2strokes.com

Yes, it's an aftermarket stator but I have a replacement charge coil to rebuild the stock stator on the way.

I already cut off the ends, bent back the tension wire, and installed the MSD clips and caps. I tried 2 coils, 2 CDI units and same thing. The last thing to do is the rebuild stator will be here next week.

 

[felix5oh]

The charge coil for the stator was backordered and wont ship until after the 15th of this month.
I mean really, I can't think of anything else. It ran great, lost spark, replaced coil and CDI and nothing, replaced with aftermarket stator and we have spark and idle but no acceleration. I got nothing else. By the sound, it feels like ignition cut out because it's a perfect dead pitch. Like a cut out, not like a stall.