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Weird starting issues, SX210

girthquake

Active Member
Messages
24
Reaction score
22
Points
32
Location
Irvine, CA
Boat Make
Yamaha
Year
2006
Boat Model
SX
Boat Length
21
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!!
 
You may have a bad injector. Get yourself the Yamaha diagnostic kit that I linked below, it will allow you to test the injectors without the engine running and you can see a bunch of parameters which may help you troubleshoot.

 
check and clean all your ground wires including the main one on the engine and electrical connectors
 
Thanks Ripler and Cobra Jet.
I did get the YDS and tested what I could without running the boat. I will try it again specifically on the injectors. I know the engine grounds are solid and clean since I just put them back on. I will go to through the battery switch connections again as well.
I really hope to figure out this annoying gremlin. To costly to run new iridium plugs every trip!
 
Another diagnostic suggestion... Same issue on a car, was a check valve in the fuel pump. Only appeared during short stops. Can you try to set the key to On, then Off 4 times leaving it on each position for a few seconds? This ought to restart and recycle the pump, and "fixed" the issue on the car until I replaced the pump.

Leaky Injector? If it happens again, try cranking a few seconds at full throttle to move some air and try again. If it starts easily after, you may have had too much fuel in the engine?

Wild thoughts.

hope you find it!
 
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.

I'm very perplexed by this comment, you pulled the engine out of the boat and replaced gaskets just for fun ????

Not saying it's a bad thing and what a great time to look at the cooling passages for sediment build up, I wish I had the ability to do that,

it would have also been nice to take the oil cooler apart for a "white goo/algae" inspection,

anyways,

what about debris/water in the fuel tank, since it's a new to you boat, there's no telling what or how long stuff may have been in the tank,

How many tanks of fuel have you ran through it ?



.
 
and welcome to the board, update your profile with your location so we know where your at (and if I can bring my boat by for you to pull my engines!)


.
 
HA! Thanks everyone. I will look at all your suggestions as soon as I can. I pulled the motor because its too damn cramped trying to look at anything in the engine compartment. I had a small pesky oil drip that I could not find either. These engines are very easy to pull after you take off the 10 miles of wiring. I made an engine stand out of an old wagon.
Oil pump was totally drained and there was some sludge in the bottom of it for sure.
I have not really inspected the tank. I will try that next. I have only run 40 or so gallons through the boat so far and I am sure the gas that was in the tank was not great.
What is weird is its only the port engine. I am leaning towards a fuel delivery issue since new plugs will start up immediately so something must be pumping too much fuel into the cylinders??
Thanks everyone for your suggestions.
 
Greetings!

Sorry to hear you are having dramas....

Reading your post reminded me of this thread... https://jetboaters.net/threads/starting-issues-2015-ar192-help.29905/

To me, your problem sounds like an intermittent electrical problem... I would definitely check the stator output, ohm readings, cranking voltage checks etc..

Iridium plugs? I like them, but are those the OEM plugs? You said you put in new plugs right after you purchased the boat... did it have iridium plugs in it when you bought it? If not, do you still have those original plugs ?

It has been my experience that some ignition systems can be a bit finicky about plugs due to different resistance levels.
 
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On M R 1 engines if the oil was overfilled just a bit it gets into the air breather element and will cause issues so check the oil level and the air cleaner element just to eliminate those things
 
Thanks FSH 210 and Cobra Jet. The boat did not have Iridium plugs in it when I bought it. I put those on based on reading a bunch of posts on here and on the yamaha forum. I will gladly throw some OEM plugs back in for the next test session. They are much cheaper anyways. It still does not make sense to me that once the engine starts, it will run fine for as long as I need to. It does not stutter or bog down, shut off, etc.

I check the oil level regularly and inspect the air filters each time. Unless there is a nother place that Oil can go to cause this problem, I assume I can rule that out.

Definitely a head scratcher.
 
I know some say that the spark plugs in the MR1 can be a problem, I owned my Yamaha for 10 years and put close to 500 hours on it and never had a spark plug issue.
 
So perhaps there is a problem with a fuel pump or a leaking injector I had an issue with an 1800 engine that had problems with the throttle positioning sensor and after running it with no issues I would go to restart it and it would just crank but not start then for the hell of it I messed with the throttle before cranking the engine and it would start I have also had issues with worn kill switch lanyards plus the MR1 boats had some loose wires behind the helm at the ignition plus some water shooting out of the speedo hoses that soaked some of the wires while the boat was in use. all things that you can check on.
 
I know some say that the spark plugs in the MR1 can be a problem, I owned my Yamaha for 10 years and put close to 500 hours on it and never had a spark plug issue.


I have run the same plug in my FI dirt bike for 8 years on the same plug... if these engines need plugs once in a while so be it..
 
Thanks FSH 210 and Cobra Jet. The boat did not have Iridium plugs in it when I bought it. I put those on based on reading a bunch of posts on here and on the yamaha forum. I will gladly throw some OEM plugs back in for the next test session. They are much cheaper anyways. It still does not make sense to me that once the engine starts, it will run fine for as long as I need to. It does not stutter or bog down, shut off, etc.

I check the oil level regularly and inspect the air filters each time. Unless there is a nother place that Oil can go to cause this problem, I assume I can rule that out.

Definitely a head scratcher.

Girthquake,

The guy I mentioned in the thread with the hard starting issue was at his wits end.. took it to the dealer and it was the stator. It was the inverse of the problem the old SEM stators used to have in dirt bikes, his boat wouldn’t start cold, but when he did get it running it ran and started fine all day. Probably a broken wire in the winding that would then make contact when it was warm..

There is another current thread with a guy who is having a starting problem, engine wont start and the flash code states a pick up coil problem. He cleans the multi pin connector and the engine starts, then after running it for a while gives the same problem, that indicates to me either a broken conductor or broken pin in the connector. These engines operate in a pretty tough environment, hot and humid, so corrosion can sneak into a lot of places.

Quite a few people, including myself, have experienced a starting problem with no apparent correlating event when the engines have been shut off then have a hard time starting later in the day after sitting for a while.. and then no problems for several outings.. my guess on that is a glitch somewhere in the injector strategy but who knows..

I hope your issue gets resolved with the least amount of effort and cost!
 
Thanks everyone!
I will run the gambit of electrical tests and YDS this weekend to rule out any obvious issues. I will also check the tank, fuel pumps, etc.
Hopefully I will find the diamond.
I have also thought about swapping stuff between the port and starboard engines to see if the problem migrates, ie injectors, ECU, etc. Any problems with doing that?
Thanks
 
You may need a little hose and a barb, but you can swap fuel hose inlets easily from one side to the other (I've done that before to troubleshoot a problem)
 
When it doesn't start...does it turn over or do nothing? I think I read that it does turn over - so its not the clean out hatch. Have you tried bypassing the lanyard...that allows it to turn over....(but YDS would show that error)
 
Thanks everyone!
I will run the gambit of electrical tests and YDS this weekend to rule out any obvious issues. I will also check the tank, fuel pumps, etc.
Hopefully I will find the diamond.
I have also thought about swapping stuff between the port and starboard engines to see if the problem migrates, ie injectors, ECU, etc. Any problems with doing that?
Thanks


Im thinking once you run some basic diagnostics with the shop manual and an ohm meter you may find your problem.. also, be sure that all of the electrical system deutch / multi pin connectors are clean and in good shape, and I’d think a bit of dielectric grease may not be a bad idea..

Please let us know what you come up with!
 
Bummer that you bought a boat with an issue like that. The good news is that it sounds like you’re more than capable of tearing into it yourself to fix the issue once you figure it out. Also, you have a spare set of parts (on the good engine to help diagnose).

It’s not totally clear whether your describing an issue where the engine won’t crank at all. Or if it’s turning over, but not firing up.

parts that you can swap to see if the issue jumps to the other engine.

1. Key switches
2. Lanyard switches (yes, there’s one switch, but a circuit for each engine)
3. Clean out hatch switches
(for key switch/lanyard/clean out switches just swap the plugs no need to remove anything)

4. Coils - could easily be your issue.
5. Fuel pumps - might be a PITA removing the deck of the boat, but the pumps are easy Once you learn how to uncouple the fuel line.
6. Fuel injectors
7. ECU’s

1-4 could be done pretty easily and if the issue transfers to the other engine, simply reverse them one at a time to figure out the real culprit.
 
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