Going threw plugs

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Wbelt

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So on my 94 Sea-Doo Bombardier, with fresh plugs I will get a hour or so of riding in and then the plugs go bad. I put new ones in and I’m good for another hour or 2. Any idea on what is making me go threw plugs so much. If they are getting to much oil are the piston rings going out?
 
And that's after only two hours.

On the right is rich but is burning good.
On the left though, grey and clean. Looks like its running lean and depositing material on the plug electrode. One seems to be fouling and the other being cooked.

I'd pull the head to see what the pistons look like at this point. I bet there is more to this issue.
 
You say the plugs are going bad?

Are those bad plugs? Or are they ones that still work but you are showing us?

To me, if someone says a plug went bad that means the machine stopped running. Those plugs should be working just fine even though they are not in identical/perfect condition.

If you had a plug fail I would be expecting a black carbon covered bunch of crud all over the end, or a melted electrode or oil/fuel soaked ends. Those are dry, in one piece and clean enough to run.

Since they are not the same I would agree with Mekanix and start looking at engine compression first. The difference in the condition is a little concerning.

Give us some more of a description of the running problem you are experiencing. Is it a total motor shut down, poor running, running on one cylinder, low power???

What model and year machine is this?
 
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Those plugs don’t look fouled at all. The first thing I would do is remove your spark plug boots and trim the wire back 1/4” before screwing them back on. You don’t need to strip any wire, just cut them flush and screw the top back on. The wires probably aren’t the issue, as weak spark normally causes a black, oily plug, but it’s an easy and free way to rule that issue out. After that, I would start looking at the carbs. Order genuine Mikuni carb kits and follow the carb rebuild sticky...
 
Tried starting up on lake after it died and it sounded like there was no spark just kept turning over. The ski will run good for a bit then lose power and feel sluggish. 94 Sea-Doo bombardier. Thanks for all the help guys! Still learning ski motors. in used to quads and dirtbikes.
 
One more question for you guys... when replacing pistons, do you have too pull motor out? The videos I keep watching all the motors are out. I know it may make it easier but I’m just curious if it’s do-able with it in the hull.
 
Pistons can be done with the motor still in the machine.

As for the kind of machine. Yes it is a Bombardier sea-doo, but what model is it? It would help us give you more information if you could tell us WHAT sea-doo it is? There are many different models, motors, carb configurations.

Based on what I'm seeing with those plugs tells me you could have one carb giving you trouble, if it is a twin carb model. But based on what you are saying it sounds like you have had a seizure of one side, possible not severe, and it is still functioning to some extent. This is a scenario I have seen play out before, I have a sled right now that runs great all day until you give a good wide open shot and it binds up one piston but will not die.

There are many possibilities as to what is going on with your machine and just rebuilding it without finding the root of the problem is not going to help in the long run.

Take pictures of the machine, motor and carb area so we can help out.
 
So I had the cylinders and carbs off. Well I turn the motor over by had so I could inspect the rods. Long story short I got everything back together. Is it possible I threw the timing off when I turned motor over by had with that stuff off.
 
So on my 94 Sea-Doo Bombardier, with fresh plugs I will get a hour or so of riding in and then the plugs go bad. I put new ones in and I’m good for another hour or 2. Any idea on what is making me go threw plugs so much. If they are getting to much oil are the piston rings going out?
chop off a little bit of plug wire and replace those caps, did it to mine and runs like new.

to remove cap just tug while turning left, installation is the opposite
 
Still just turns over. Is it possible I threw the timing off when I turned motor over by hand. When I had the cylinder and carbs off?
 
If battery is weak will that make weak spark? Asking because when I go to start it it will sound like a strong battery and then almost right away it sounds like a very weak battery.
 
Yes, a weak battery can translate to weak spark. You need to fully charge that battery or replace it before you dig too deep into the motor trying to diagnose. I doubt that’s the cause of the foiled plugs though.

The timing should not have changed unless you removed the rotary valve, but it wouldn’t hurt to check it if the battery doesn’t take care of the issue. Do a search for how to degree the rotary valve, and it will tell you the process.
 
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