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motor breaking down

Yamatuf

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Year
1999
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I have a ls2000 gp1200 motors. The right side motor is having rev issues to which it breaks down. To me it seems like an electrical issue. I changed the plugs twice as a double check, changed the fuel filter. I recall a similiar issue a few years back to which I changed the plug wire boots on the same motor, problem solved. Is this common? Should I change the whole wire and boot.

Is there snything else I can look at within the electronic system. When running the boat the motor will jump from 4000rpm to 5200rpm and then back. this happens when cruising with both motors set at the same throttle. It sounds to be laboring eithor no fuel or loosing power then power back up. Plugs looked good. Up against the clock, my whole family is up for weekend at the river.
 

itsdgm

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Intermittent Problems like that can be frustrating!!!! It could be one of several things ranging from a simple loose wire connection or a fuel delivery problem. Have you ever torn down and rebuilt your carbs?
 

jdonalds

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The biggest problems I've had with 2-strokes was running too lean. The engines behave erratically before they froze up and toasted a cylinder or more. Be very careful no to run the engine too much while you figure out what is wrong with it.
 

Yamatuf

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Thanks for the input. I purchased new carb kits this spring but didn't have time to rebuild, my extended winter project?? I am still leaning toward the plug wires / boots. The problem started after I changed the plugs this weekend since the same motor was loading up and having difficulties starting - restarting. Since I changed the plugs It ran fine for several tube rides with the kids before the issue raised it’s ugly head.

I will change the boot to start and work down the list. Unfortunately the boat is at the weekend house and I am traveling this whole week. I will have Sat. morning to troubleshoot and fix.

This was suppose to be my last main weekend of boating/tubing etc. due to the commitments for travel soccer. Goodbye weekends, hello travel!!! Things we do for the kids!!

Great forum, everyone is so helpful. One day I will have to meet up with some local jet boaters!
 

Bruce

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Does the engine run above 5200 rpm?

I remember that my LX210 was hard to control in that rpm range. It would quickly rev from 4000 to 5200 making it really difficult to try to run 4500 or 5000 rpm. My understanding was that this was due to intake design.

Have you checked your oil lines recently?

Sea Foam helped with occasional stalling in my engines. I did not use ethanol gas in it but I believe the previous owner did. I used sea foam in every tank until I felt the ethanol had been cleaned out.
 

Glassman

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"The problem started after I changed the plugs this weekend"

I'd go over everything you did, step by step. Could be wires that were marginal and are now toast after being disturbed, or not properly seated.
 

itsdgm

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I agree with @Glassman. Start first with what you changed that made it run differently. You might simply have e a bad spark plug.

What @jdonalds said is very important too. Running lean will burn up a cylinder. So pull the plugs often and inspect until you get it figured out.
 

JC6275

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Pull the wires on the non affected motor and put them on the problem one, this should either identify the problem or rule it out.
 

JC6275

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With the fluctuation between 4000 and 5000 rpm, it sounds more like a fuel issue, like it's intermittently not getting fuel. Check the filters, and fuel line connections to be sure they aren't sucking air.
 

Yamatuf

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Happy Labor day everyone! To follow up with my issue there was 2 problems.
1. The plug wires were failing, corroded - I cut and spliced temporary set, things improved.
2. Still having issues when increasing throttle. I could play with the choke and successfully keep the motor running smooth up to apr. 5300 rpm then things would level off and start the issues mentioned above. Makes sense the motors are starving pointing to a carb issue.

I will break down the carbs and rebuild all 6 and check fuel lines from front to back. I will also be replacing the plug wires but have a few Q's.

1. Jetski solutions offers a wire replacement service that seems fair, I will determine If i should do myself.
2. Is there anything I can do with the coils or do you just have to buy new coils?
3. Is it worth upgrading the stator or ebox service they provide? I stay remotely on the potomac river to which I can paddle to land if needed. The boat is a 2000 and just wondering how long will the electronic components typically last or is a good time to upgrade before failure.

CHEERS everyone, half way to happy hour
 
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