No spark in Port Engine of 2000 LS2000

[jjtherocketman]

Have looked through threads here seeking a "no spark condition" but haven't found anything that seems to fit yet. I have a 2000 Yamaha LS2000 with twin 135hp motors. Boat has been running great, but last time out, had port engine die on me and had to limp back in. Since that time, I've checked all of the obvious kill switches (lanyard, clean out port switches, ignition switch, and neutral switch). Checked resistance on all and they were all correct per the manual, and then even swapped connections on each. In all cases, starboard engine still fires right up and port turns over, but doesn't appear to pop and start. Appears I have good gas flow, changed fuel filter and that filled right back up. Tried starter fluid (usually need starter fluid to start either engine after they sit for a few days once gas drains back into tank), but that isn't getting any pop out of the port engine either. Plugs look fine. Think I have it narrowed down to the ignition system box on the back bulkhead as a result of all the other checks. Has anyone had any experiences with some component failing in that box? CDI?

Any suggestions would really be appreciated

 

[tdonoughue]

I agree it sounds like an electrical problem. I would get a plug tester. You pull the boot and plug it into the tester, then plug the tester into the plug (more reliable, easier, and a bit safer than trying to hold the plug out of the cylinder and cranking). See if it lights. If not, you have no spark.

Double check the lanyard switch. That one will let the engine crank, but will not allow spark. Looks like you checked that; check it again (it will become clear in a minute).

Once you have no spark determined, if it is on one cylinder, there are basically two reasons that can be: a) computer or 2) coil. Pray it is the coil. Swap that with another coil and see if it sparks. If so, your coil is bad; buy a new one. If your ECU is bad... those are pricey. I think there is an outfit that rebuilds them. Search for ECU here on the board.

If there is no spark on all cylinders, I'm afraid you are back at the ECU.

 

[jjtherocketman]

I agree it sounds like an electrical problem. I would get a plug tester. You pull the boot and plug it into the tester, then plug the tester into the plug (more reliable, easier, and a bit safer than trying to hold the plug out of the cylinder and cranking). See if it lights. If not, you have no spark.

Double check the lanyard switch. That one will let the engine crank, but will not allow spark. Looks like you checked that; check it again (it will become clear in a minute).

Once you have no spark determined, if it is on one cylinder, there are basically two reasons that can be: a) computer or 2) coil. Pray it is the coil. Swap that with another coil and see if it sparks. If so, your coil is bad; buy a new one. If your ECU is bad... those are pricey. I think there is an outfit that rebuilds them. Search for ECU here on the board.

If there is no spark on all cylinders, I'm afraid you are back at the ECU.

Seems like you skipped over the Stator as being a possible problem? That's what's being suggested on the "other jetboat forum" lol Apparently those have become loose or inoperative on some as well. That would/could also kill your spark. In regards to your coil possibility, if it was just one dead cylinder, I would still get some pop, possibly even start, albeit very roughly. I'm not getting anything when the motor turns over. ECU seems a bit odd to have just up and died all at once out on the water? I suppose if it was some sort of ESD event that zapped it, maybe a current surge? I'm sure there are probably a few other electrical gizmos in that ignition module that could have also crapped out. I'm just not good with electrical diagnosis unfortunately and unless someone has an easy way to check them with an ohm meter, I won't ever find it. I may be getting closer to taking it to a jet ski tech in my area since I've ruled out the kill switches now.

Reason I've ruled out the lanyard is because I unplugged and swapped the two lines to each engine. IF it was that lanyard switch, it would have killed the good engine and allowed the non-starting engine to fire. It didn't. Also checked it with an ohm meter and it followed the appropriate state change as listed in the manual. But I DO appreciate the reply. I have to keep all possibilities in mind, but much prefer eliminating as many as possible before I start buying parts that I don't need....especially very expensive ones! ;-)

 

[tdonoughue]

I did skip the stator--that is a very valid point. In fact, I think that the LS2000 does not have individual coils, right? You just have the stator. That certainly could be the culprit. I don't have a stator on my boat, so I would be pretty weak at diagnosing that one remotely. I think those are the engines that have issues sometimes with the magnets on the flywheel. But certainly agree that should be on the list. Right after the lanyard switch (which it sounds like you have well ruled out--didn't mean to imply you didn't do a good job of that. it is just that fix is so easy and the others so messy...).

See, this is why you shouldn't put full faith in the help of someone with a 2012 when working on a 2000.

The ECU's have been known to just die at times. Sometimes there is water infiltration; sometimes they just croak. But it is an expensive part that is a real pain to change (I think they are paired to the engine or something--never replaced one myself). But they can cause all sorts of strange problems (stuck injectors, failed spark, etc.). Like I said, check everything and if everything checks out, then you consider the ECU. But it would be a mistake to think it could not possibly be the ECU...

Do you have the shop manual to test the stator? Do update us on your next steps. This is how we grow the knowledge...

 

[jjtherocketman]

I am by NO MEANS any form of an expert on these boat motors. Only just bought the boat before Christmas LOL. There are individual coils on the LS2000, but I don't see it likely that all 3 coils kicked the bucket at the same time. One going out should just cause it to drop one cylinder, but I would have thought it would still run, just REALLY rough.

As for the ECU, I don't really know much about it. This boat has an ignition module for each engine on the back bulk head that can be opened up. Inside it appears to have a CDI, coils, and some other electronic gizmos. I'm a mechanical guy, so chasing sparks ain't my forte. Still learning how to diagnose some of these electrical things....simple resistance checks with an Ohm meter I can do....gets more complicated for me after that. I certainly don't want to drop a ton of coin on some of those electrical components if they aren't bad, so for now, it's digging through Youtube looking for videos that might help shed some light on how to diagnose this "no spark" issue on similar type engines like jetskis. I'm open to any and all help and suggestions certainly. Keep em comin', I'll attempt it if someone can give me good enough directions! If I don't get any help, may end up taking it to a jetski guy to put on an engine analyzer or whatever they have to try and diagnose it. But prefer to do it myself if I can find the issue.

 

[tdonoughue]

Yes, all 3 coils did not dump at the same time--fully agree with you there. Not sure if your engines run a cylinder down (I know a 4 usually will, but rough, but I think you have 3, right?). But I would expect that if you have at least 1 working you would hear something when cranking. I assume you are not hearing that (that it is an even starting sound with no spark, rather than 'hitting' momentarily while trying to start).

I don't know of any diagnosis for the ECU other than process of elimination. I am sure that with more advanced tools that you can check something there.... but that would be beyond my capabilities, too.

Do you have a YDS for your boat? That can also give clues (if you can get it working).

But we get ahead of ourselves. Have you checked spark on all plugs first? Let's start there.

 

[jjtherocketman]

No spark, and no pop sounds of any kind when turning it over....don't know what a "YDS" really is? Some sort of diagnostic system?

 

[Brad_Ct]

I know on my Exciter there is a fuse in the left side of the CDI box. There should be a wire going into a rubber plug, pull the rubber piece out and the fuse is behind it. I believe both boats are pretty much the same other then your CDI box is mounted behind the engines where mine is mounted on the front of the engine.

 

[jjtherocketman]

Yep, my Dad and I were investigating that last night. There appears to be a knob with something behind it in an illustration in the manual that isn't labeled, but looks kinda like a fuse. I'll be digging around looking for possible fuses that are out.

 

[mrcleanr6]

i had the mr1 engine in my wife's ski and i can tell you the ecu's do fail and its not a super rare occurrence. when all else checks out ok then you just need to change it. as previously stated, its just process of elimination.

 

[jjtherocketman]

i had the mr1 engine in my wife's ski and i can tell you the ecu's do fail and its not a super rare occurrence. when all else checks out ok then you just need to change it. as previously stated, its just process of elimination.

Yea, I get it, but I'm not done eliminating all the other possibilities first LOL. Spending $500 on a part blindly in hopes of it solving my problem isn't how I typically go about fixing things. If I had lose change laying around, I probably would have just ditched the boat and bought a new one and been done with it! hahaha. I know that's not what you're saying, I mean no disrespect. What I'm seeking here is as much advice on how best to diagnose and find the problem, step by step. Rule out the big ticket items ($$$) that don't need to be replaced and just replace the item(s) that do need it. All good, keep the comments coming.

 

[mrcleanr6]

absolutely. the ecu should be the last item on the list. just saying that it does happen and dont rule it out

 

[jjtherocketman]

absolutely. the ecu should be the last item on the list. just saying that it does happen and dont rule it out

Much appreciated. Almost anything can break, and yes DOES when you least expect it! I think the bottom line is, the only way an average back yard mechanic will find answers to some of these components being bad is having a machine that can communicate with the electronics to find the faults. I've always found ways around needing an analyzer in the past on my cars, and there have been inexpensive versions of the diagnosis equipment developed on cars, is there any such thing for these 2 stroke boat engines? I honestly haven't even looked for one yet.

 

[tdonoughue]

YDS is the Yamaha Diagnostic System. Connects to the ECU, reads all of the codes and other diagnostics on the engine. Very helpful. You can get them on eBay, but check to see if it works for your year. Also, if you are not up for buying one of those, add your location to your profile and see if someone is near you with one. They get lent out all the time...

 

[jjtherocketman]

YDS is the Yamaha Diagnostic System. Connects to the ECU, reads all of the codes and other diagnostics on the engine. Very helpful. You can get them on eBay, but check to see if it works for your year. Also, if you are not up for buying one of those, add your location to your profile and see if someone is near you with one. They get lent out all the time...

Just added location on profile, Mims, FL. Wasn't aware of the YDS, I'll look into it.

 

[jjtherocketman]

Just added location on profile, Mims, FL. Wasn't aware of the YDS, I'll look into it.

I just looked into it, doesn't appear that YDS works on Carbureted engines? Which kinda makes sense I guess. My LS2000 has 3 carbs per engine.....no fuel injection.

 

[tdonoughue]

Drat. Was afraid it was before YDS... ah, well. Sorry about that.

 

[the MfM]

Yep, my Dad and I were investigating that last night. There appears to be a knob with something behind it in an illustration in the manual that isn't labeled, but looks kinda like a fuse. I'll be digging around looking for possible fuses that are out.

There is a fuse behind that knob. Unscrew it and they’ll be a bunch of wires that you can pull out to find an in line fuse.

Sounds like you don’t have an in-line spark plug tester? If you don’t I’d recommend getting one as they save a lot of time chasing electrical gremlins. You can see if you have spark or not in seconds. Then move onto compression testing before messing with the fuel system.

(No need for that YDS stuff with engines this simple)

 

[the MfM]

And you should never need starting fluid...rebuild the carbs!!!!

 

[tdonoughue]

Ah, we have @the MfM in the house. Finally, an expert on these engines...

Do you know a diagnostic procedure for the stator?