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Weird starting issues, SX210

Beachbummer

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Just a thought...No need to swap the fuel pumps, to test, just swap the fuel lines into the engine.
 

girthquake

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You are all awesome. Great ideas, and I will dig into testing this weekend. I will confirm that the engine does turn over when the starting issues occur. Also, I will add that sometimes it "tries" to start before it actually fires. You know when you can hear that its firing a little, or maybe on some cylinders, then bam, its up and running.
I already had the deck off to replace the fuel lines so no big deal pulling it up again.
 

girthquake

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Update:
checked the electrical specs on the coils, injectors, kill switch.
Could not find a ton of specs to test from the repair manual I have, Most require 3,4,5,6 pin Ohm readers. I just have a 2 pin.

Pulled both fuel pumps and inspected the tank. Tank is clear and I went ahead and swapped the fuel pumps.
Next step is to put 8 OEM plugs back in the boat, fresh fuel, go for a spin. If I can rule out the fuel pumps, I will start swapping other items.
Still perplexed. It only seems to do this after running for a while in water. It will start on the trailer every time. And it always starts, the first time at the dock.
Thanks again for all the advice. I will report back if I find anything else.
 

FSH 210 Sport

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Update:
checked the electrical specs on the coils, injectors, kill switch.
Could not find a ton of specs to test from the repair manual I have, Most require 3,4,5,6 pin Ohm readers. I just have a 2 pin.

Pulled both fuel pumps and inspected the tank. Tank is clear and I went ahead and swapped the fuel pumps.
Next step is to put 8 OEM plugs back in the boat, fresh fuel, go for a spin. If I can rule out the fuel pumps, I will start swapping other items.
Still perplexed. It only seems to do this after running for a while in water. It will start on the trailer every time. And it always starts, the first time at the dock.
Thanks again for all the advice. I will report back if I find anything else.
Thanks for the update!
 

Mustangswan

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here is a list of things I would be looking at after checking to see if there are any codes in the pcm to get you in the right direction.

fuel pressure and leak down to see if you might have an injector leaking down or pump issue. They can be intermittent. Let the gage stay on there if you can and monitor the pressure after sitting.

While you are cranking the motor you should be able to hear the injectors ticking if they are working, which if they are not, would lead to something like a stator, possible sensor not allowing the injectors to work, like a TP sensor or pcm/ecu problem Use a long screwdriver and place tip on the injectors and hold the handle against your ear. it will be obvious if they are working electrically. (Ticking noise)

Check spark. There are in-line spark testers that could be installed to test even on a coil-on-plug design, or for about $100 you can get an inductive type that looks like a little fly swatter on the one end that you just hold over the coil.

Timing, which I don’t know if there is a way to check on that motor with like a timing light. but would tell you if the pcm is seeing a stator signal. If you could find the wiring pin location on a connector to check the Ohm reading of the stator while hot would also be helpful. It should just be 2 wires. Then also check for resistance to ground also.

Sounds like a winding getting hot and opening like a stator , then when cooled down works again. See that a lot on car motors. Have also see water and corrosion cause an issue like that, but if you had all the wiring off the motor I would think you would have seen something.
hope these tips narrow down your issue.
I tell my apprentices
“Remember Suck -Squeeze -Bang -Blow makes the engine go.”😂
 

FSH 210 Sport

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Update:
checked the electrical specs on the coils, injectors, kill switch.
Could not find a ton of specs to test from the repair manual I have, Most require 3,4,5,6 pin Ohm readers. I just have a 2 pin.

Pulled both fuel pumps and inspected the tank. Tank is clear and I went ahead and swapped the fuel pumps.
Next step is to put 8 OEM plugs back in the boat, fresh fuel, go for a spin. If I can rule out the fuel pumps, I will start swapping other items.
Still perplexed. It only seems to do this after running for a while in water. It will start on the trailer every time. And it always starts, the first time at the dock.
Thanks again for all the advice. I will report back if I find anything else.
Any updates?
 

girthquake

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Hey everyone. I finally had the opportunity to run the boat again.
First off, I put in brand new OEM plugs just to test. I also added seafoam to 15 gallons of fresh gas.
Took it out to the bay/harbor area in Long Beach and let her rip. Not to beat a dead horse, but it fired right up and ran like a champion. 7K for 20 minutes cruising around absolutely perfect. I figured after that it was time to test. I shut it down for 15 minutes and once again, port engine did not want to start. So we idled for a bit on the starboard, heading towards the harbor entrance. I attempted to start the port engine every couple of minuted until after 10-15 tries, it started to make the sound like it was trying and then it finally fired right up! After that we ran back in to the harbor and I immediately shut it down, waited only 15 seconds and attempted to restart again. It started right up. SO maybe it will start up right away but not after a break.

What I learned is that it was not the fuel pumps and it was not the OEM/Iridium plugs.
I guess the next step is swapping the injectors and then eventually the ECM??

I like the idea of the stator but not super knowledgeable on how to test that on these boats. ANy advise would be great.
We want to keep this boat but do not feel safe knowing we cannot always rely on 2 engines to bring us home safe.

Thanks again for all your advice and encouragement.

HAPPY NEW YEAR!
 

Street glide

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This is my first post on this site, however, I have been lucky enough to learn much from many of you so far!
We purchased a used 2006 SX210 back in June. Low hours, started up and ran, all looked great. I put in new plugs just so I had a baseline.
1st real trip we launched and the boat ran great for 20-30 of cruising and getting to know the Jet boat.
Stopped for a bit and the port motor took a while to restart. Didn't think too much of it as it started up again right away each time we stopped.
After our second trip, we noticed the port engine did not like to start after a prolonged break. Sometimes it would take a long time to get it to start.
As soon as it started, it would run great with no problems!
On our third trip, after our initial cruise, we stopped for lunch and the port engine refused to start. We idled back to the ramp and went home.
I swapped the plugs from the port and starboard and the port engine fired right up and the starboard would not start so all new spark plugs went in and then both engines ran fine again.
We went for a weekend trip and the first day the boat ran great until another prolonged break...Then the same issues happened again.

After this trip I pulled the Port engine and just for fun replaced all gaskets and cleaned all that I could while having the engine out. Injectors looked clean and brand new almost. Replaced fuel lines and put in K&N air filters. Put the engine back in the boat with new plugs. Filled with oil and new oil filter. Started on the hose, ran for a while. All tested fine. Saturday we took the boat out for a test run. Port engine started right up and ran great. Oil levels great. Purposely turned it off after running for 5 to 10 minutes to see if starting issue happened again. After two or three times, we turned off the boat and floated having lunch. Finally, it happened again. Port motor would not start. After trying intermittently for 10 minutes, it finally started and ran rough for 15-30 seconds, then, it jumped to running smooth. Ran fine the rest of the day as long as we didn't stop for long periods of time.

Very weird.
It is almost like the plugs are getting fouled and it will not start until they dry out. If I start up right away after stopping, all is fine. If we sit for a bit, this seems to be the problem.
Could this be electrical? Fuel pumps are working. Is an injector sticking after we turn off the fuel allowing them to fill the cylinders and flood the plugs?
If I put brand new plugs in, it will start immediately every time.
Any advice would be greatly appreciated!!
What was the numbers for the k/ n air filters you used
 

FSH 210 Sport

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Hey everyone. I finally had the opportunity to run the boat again.
First off, I put in brand new OEM plugs just to test. I also added seafoam to 15 gallons of fresh gas.
Took it out to the bay/harbor area in Long Beach and let her rip. Not to beat a dead horse, but it fired right up and ran like a champion. 7K for 20 minutes cruising around absolutely perfect. I figured after that it was time to test. I shut it down for 15 minutes and once again, port engine did not want to start. So we idled for a bit on the starboard, heading towards the harbor entrance. I attempted to start the port engine every couple of minuted until after 10-15 tries, it started to make the sound like it was trying and then it finally fired right up! After that we ran back in to the harbor and I immediately shut it down, waited only 15 seconds and attempted to restart again. It started right up. SO maybe it will start up right away but not after a break.

What I learned is that it was not the fuel pumps and it was not the OEM/Iridium plugs.
I guess the next step is swapping the injectors and then eventually the ECM??

I like the idea of the stator but not super knowledgeable on how to test that on these boats. ANy advise would be great.
We want to keep this boat but do not feel safe knowing we cannot always rely on 2 engines to bring us home safe.

Thanks again for all your advice and encouragement.

HAPPY NEW YEAR!
My first stop would be having the stator checked. Check the ohm readings cold and then when hot, your issue is apparently heat related. I’m betting that this will prove to be your gremlin. On the older motorcycle stators what would generally happen when a wire broke inside the windings the bike would start fine and run until it got then quit. You’d wait 45 minutes and the bike would start right back up again. The thermal expansion would separate the wire down inside the winding and when it cooled off the wires would touch again.

There was another guy here who had bought a used boat and his boat started having issues just getting started but after it would start would run all day. He finally took it to a dealer and they found a bad stator. Once replaced he has been a happy boater ever since.

Intermittent electrical issues are a bear.. sounds like it may be time to have a dealer look at it. If not the dealer you’ll need the diagnostic plugs so you can take ohm readings. This a relatively inexpensive thing to check off the list.

Next would be leaking injectors. By your description and my experience it sounds like it could be a leaking injector. Maybe when it won’t start pull a or all of the plugs to see if they’re wet with gas.

I can’t remember without going back and reading, check all of your engine related multipin connectors for cleanliness and put a little dielectric grease in there.

Remember... when everything that is plausible has been eliminated, whatever remains however implausible has to be the answer.
 
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girthquake

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Thanks FSH210
I will try and find the ohm connectors. I will see if anyone on here has figured out the best way to check the stator. I wish there was a good dealer in my area so I could just let them deal with it. I have yet to find a reputable yamaha marine mechanic out here.
I will keep looking and take the boat out agian this weekend if I can.

Street Glide. here is the K & N filters that I bought. They fit in my existing air filter boxes, the round ones. All I had to do is shave a little bit of the rubber off the inside of the filter. Now I have two re-useable and cleanable filters.
 

Street glide

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I also have the rounds ones couldn't get the link to work do you happen to have the number
 

buckbuck

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I have not gone back to read the earlier posts but are you sure this simply isn't the lanyard switch? Try pulling the lanyard and then pull and release the plunger. Exercise it a number of times and see if that repairs your issue.
 

FSH 210 Sport

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I have not gone back to read the earlier posts but are you sure this simply isn't the lanyard switch? Try pulling the lanyard and then pull and release the plunger. Exercise it a number of times and see if that repairs your issue.

Yes he checked all of that.... only one motor doesn’t start, the other starts fine. It’s a good suggestion.. such a simple thing can bring the whole fun bus to a stop.
 
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FSH 210 Sport

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Just had a thought and I don’t believe you addressed it yet... itsdgm mentioned the clean out port kill switches... did you check them out?
 

Cobra Jet Steering LLC

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Just curious if you checked the throttle positioning sensor, I had a ski that would do that so when it did not start but it did crank over, I would snap the throttle a few times and it started immediately, on your boat next time it refuses to start move the throttle lever back and forth a bit and then try it.
 

girthquake

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Thanks everyone. I did test the kill switch as well as the clean out switches. In theory, either one should not be the issue since it will eventually start, most of the time. And on that same note, the engine should be shutting off randomly if there was an intermittent connection from either and once it starts, it stays on until I shut if off.
 

Cobra Jet Steering LLC

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did you check the throttle positioning switch it sure sounds like that could be your problem
 

girthquake

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My service manual does not list a stator. I assume the "Generator" is what they are calling it. Maybe I have the wrong manual? Trying to find the diagnostic parameters for it.
I attached a picture of my service manual. Maybe I have the wrong one?
 

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