Spark Plugs changed now a differnt sound?

[vandamit]

Quick background, I changed the spark plugs this weekend on my 2011 60hp Mercury 4 stroke. This is something I've never done. I got the champion plugs from Orilleys. I had never gaped plugs before so they did it in the store for me. This was a fairly easy change, it took me less than 15 minutes to change them all. When I went to the lake last night for the first time I notice when the boat is in neutral it has a different sound to it that it usually does now? When i drop it in gear it sounds fine though and seems to run more responsive and and overall I thought it ran fantastic but when you put it back in neutral it sounds weird to me. I attached a video we shot. Any ideas what I might of done wrong if anything? I did pull the spark plug wires off with some pliers but i don't think that would have caused any issue for noise? It's kind of that click click click sound you hear. SERIAL NUMBER: 1C162367

[Sleepy111]

If you used pliers pulling the caps off it could be possible you may have cracked or split the rubber boot and it could be arcing but it would be all he time not just in neutral. Connect it to water at home and run it with the cowling off or if you can’t then back it in at the ramp and run it on the trailer with the cowling off where you can watch the plug caps and see if it’s arcing outside of the cap. The clicking sound would also be close to the same sound if you were pulling the cap off the plug as it was running after it was off the top of the plug.

[vandamit]

If you used pliers pulling the caps off it could be possible you may have cracked or split the rubber boot and it could be arcing but it would be all he time not just in neutral. Connect it to water at home and run it with the cowling off or if you can’t then back it in at the ramp and run it on the trailer with the cowling off where you can watch the plug caps and see if it’s arcing outside of the cap.

So i would be able to see something if it was arching? Thanks for the tip, i appreciate it.

[vandamit]

Had a guy tell me it might be prop chatter which I had never heard of before today?

[vandamit]

I put the old plugs back in and took it back out last night and it's still doing it, so it's not the plugs. I'm guessing it might be prop chatter which was suggested to me on another thread. I had some lower unit stuff done (seals, oil, water pump etc) earlier this year and I hear it's common to get prop chatter after doing that. I have the reflex hub in my prop, is it possible for them to wear out?

[vandamit]

I did find a cut in a spark plug boot that i caused. would this effect anything though? 20200708_122632.jpg

[Avanti]

It can’t be prop chatter, the weird noise occurs when the prop is not rotating.

[vandamit]

this only happened after i removed the spark plugs an the plug wires. I pulled the plug wires with pliers so i'm wondering if i have damaged them. I put the old plugs in and it's still there so retracing my steps makes me think it's the plug wires perhaps?

[Fishysam]

Are you sure you put them in tight enough?

[vandamit]

that's a good question. I always heard not to over tighten them?

Are you sure you put them in tight enough?

[vandamit]

plugs.jpg

[vandamit]

old plugs.jpg

[EuropeanAM]

Plugs should be torqued to specifications.

And yes, that plug wire will need to be replaced (it has been damaged and will leak, if it is not already).

[vandamit]

Update: found that a bolt had come out of the power head right above the #1 spark plug and had found its way under throttle cable. You could see where it had dug in even. 99% sure this was the issue. 20200710_174412.jpg

[EuropeanAM]

Good catch!

[vandamit]

bolt.jpg

This is where the bolt came from. Picture is of the bolt after I found it and reinstalled it. I have no idea how long it's been out. I've owned the boat since it had 5 hours on it and I've never gotten even remotely close to touching that part. Hell I don't even know what that bolt holds or what that area is called? Only thing I've done is change the oil and spark plugs and had some lower end unit work done this spring.

[EuropeanAM]

Looks like a cylinder head bolt from what I can see in the picture. If it is the ONLY loose bolt I would not be overly concerned.

[vandamit]

still making the noise even after putting the new plugs in and plug wires back in. Maybe the noise isn't that bad? it's running fantastic though. Had a guy tell me his did that after an impeller change and just run it and not to worry about it.

[EuropeanAM]

Admittedly... I've not been able to ascertain exactly what sound you're worried about, so it's probably best that you use your own judgement- if in doubt (at all), have it checked out by a technician that can place his hands, eyes, and ears on the engine.

[vandamit]

Admittedly... I've not been able to ascertain exactly what sound you're worried about, so it's probably best that you use your own judgement- if in doubt (at all), have it checked out by a technician that can place his hands, eyes, and ears on the engine.

i actually appreicate that honesty Don. I just felt like it sounded loud for a little 4 stroke efi. I'm not sure i ever noticed it much until my passenger (brother) pointed it out to me. I dove into it today and started screwing around the shift linkage and throttle cable. I had a friend over that thought he could hear something to but after I got done messing around with it he said he can't hear it now.....I don't think I did anything (i'm no mechanic) but he swears it sounds better. Honestly it's hard to tell in the drive way on muffs I guess I need to take it to the lake. I do believe it used to be quieter than this when I first bought it but who knows. So far it idles great in gear and runs great so i'm guessing that's all I should worry about at this point.