Possible Broken Spark Plug... HELP!

[Mattdog501]

Hi Everyone,

I finished my 10 hour service with what I thought were no issues. Oil change... Check! Filter Change... Check! Greased and Lube appropriate areas... Check! I was feeling so confident in my new found abilities that even though the 10 hour service doesn't call for it, I decided to change the spark plugs. After reading postings I knew they can be a bit tricky to get out so I was careful.

I started with the port engine and the very first plug I tried would not budge. I sprayed the necessary silicone, waited for it seep into the threads, and on my second attempt The wrench sharply moved. OH NO! I put the wrench back in and of course it just spun while the plug stayed in. I put my finger down and I can feel a little movement on the plug itself, but not much. I decided I wasnt going to try anything of the others!

I fired the engines up, expected a disaster, and to my surprise it sounded as it always does. I took the boat out and the RPMs were the exact same. No issues accelerating or anything I would expect if a spark plug was broken.

Admittedly I am not a mechanic... Although Im quickly learning. Should I be concerned with what happened? It seems the boat ran just fine so Im not sure if I should keep messing with it or just wait till the 100 hour service? Something definitley happened because the wrench shouldnt just spin like that, but I would think Id know if the cylinder didnt fire right?

What do you all think? Any Advice. Im hoping this scenario has happened to someone here and you can walk me though what you did.

Thanks for the help!

 

[Cobra Jet Steering LLC]

perhaps you had a spark plug socket that was the wrong size and just spun on the plug making you believe it broke because if it did break the threads would stay in the head and the rest of the plug would have come out

 

[Mattdog501]

Great Point. My only concern is at the start the wrench was tight and would not move. Then all it did was freely turn... I used a normal spark plug socket.

 

[Cobra Jet Steering LLC]

those plugs use a small 5/8ths socket

 

[Mattdog501]

This is what I used... maybe I stripped the threads or something and the plug is seized. The strange part is the socket was tick until that sudden turn, then it just spins but doesn’t pull anything out.

ARES 70045-3/8-Inch Drive by 5/8-Inch Magnetic Swivel Spark Plug Socket - 10-Inch Swivel Extension Permits Access to Most Confined Areas

 

[Cobra Jet Steering LLC]

well look into it closer because I doubt the plug broke if it did you could just pull the top part out with your fingers

 

[Mattdog501]

I’d also see it notice some sort of performance issue with the engine right?

 

[Cobra Jet Steering LLC]

Forget the swivel crap use, an extension and socket on a ratchet also if you ever think you broke a spark plug never run the engine until you either determine it is not the case or you remove all the broken plug and be sure the porcelain did not break and get in the combustion chamber as this would probably ruin that cylinder.

 

[Mattdog501]

Thank you for the advice. I’ll check it good before the next time I take it out. If it is broken what’s the next step? Call the dealer?

 

[Cobra Jet Steering LLC]

first see if it is broken then worry about the next step I don't think it is

 

[Gym]

As Jeff stated if nothing came out you may not have broken anything. Get a light in there. Even if the top porcelain part broke off you still have the nut attached to the lower threaded part so you can use the socket to remove it. If there is anything broken I would vac out any pieces before going any further.

 

[dlkhmk]

Maybe completely off, but is it possible your ratchet / swivel gears broke in the wrench and it’s actual not turning the spark plug???

Only thought of this cause I recently had a ratchet wrench snap inside the gears while I was replacing brakes

 

[mwalker4]

Try the wrench / socket on another plug or nut. See if it's the problem.

 

[Mattdog501]

I have t been back to the boat yet but I was thinking about what happened again, along with reading more posts.... could it be possible the plug actually broke away from the threads themselves? I see in some cases the plug is still in tact, but the threads break away.

Any thoughts on what to do if this is the situation?

I’m thinking of carefully checking to see if it’s spinning freely ( like I think it will) then getting needle nose pliers and seeing if I can pull the plug up without and force.

 

[Gym]

I have t been back to the boat yet but I was thinking about what happened again, along with reading more posts.... could it be possible the plug actually broke away from the threads themselves? I see in some cases the plug is still in tact, but the threads break away.

Any thoughts on what to do if this is the situation?

I’m thinking of carefully checking to see if it’s spinning freely ( like I think it will) then getting needle nose pliers and seeing if I can pull the plug up without and force.

That is the usual scenario. That means the top broke off and should come out of the hole. Have you retrieved anything from the spark plug hole to support this?

 

[haknslash]

I know you said you aren't mechanically inclined, so please don't take this as a knock, but you did loosen the correct rotation? Right tight, left loose.

To check to see if it's your socket tool, if you have a table vise put a hex bolt or old spark plug in the vise and then see if it's your ratchet or socket. I've had cheap ratchets break without abusive force. I've never seen spark plugs so tight on these boats and honestly they shouldn't be super tight on such a new engine where you need penetrating oil. Ratchet spins to the left to remove the plugs.

 

[Mattdog501]

I appreciate the feedback! So the situation actually turned out to be fine. Taking the advice of everyone, I threw out the swivel socket attachment and got the standard 5/8 spark plug attachment with a solid extension. Apparently the original socket slipped off the plug nut hard, which loosened it, but I freaked out and thought it broke. I was afraid to put the socket snuggly back on! When I went back with the right socket which has the rubber insert for the top I could feel it go back on the nut and I hand turned it to where the plug came out perfectly.

The good news is now I am prepared if something bad does happen!

Of course I feel like an idiot but I’d rather feel bad vs having to call the dealer!

 

[mwalker4]

Great to hear. I've did my 10 hour a month ago, but didnt touch the plugs because of all the different discussions about breaking them. Figured I would wait until after the season.

 

[Cobra Jet Steering LLC]

ok, not a bit surprised that the plug was not broken

 

[Mattdog501]

Ha! Well thank you for telling me the swivel socket was trash.... it was!!!