Question for Wrenchin2

[Nomad 1500]

James
I have a '95 Mariner 115hp 4cyl. Saturday it developed a tapping sound that is related to engine speed but much slower than engine rotation. At 3500 rpm it's about once a second. Can't hear it at idle. The only thing I can guess is that it's somehow related to the oil injection although that's been disabled (not by me, I bought the motor that way) I premix oil & gas. What should I be looking for? Does it sound like something serious? Thanks

 

[wrechin2]

Would have to hear it. Tooooo many possibilities. Flywheel magnets, crank bearing, broken ring, lower unit issue, ect.

Doubt a oil injection issue. It is more than likely eating itself up. Pull the plugs and look at the plugs and pistons. If you see one that is dinged up, it probably broke a ring. Just a guess not seeing or hearing it. Wish I could be of more help. Sorry!

 

[Nomad 1500]

Thanks for responding. I'll check the plugs

 

[wrechin2]

Let me know what you find.

 

[Nomad 1500]

Other than a little wear the plugs look fine. None of them are beat up. Electrodes are all intact.
When can you have a look at it? (I don't expect any freebees!)

 

[wrechin2]

Will be next week before I can take a peek at it. I have to finish up a modified 2.5 for a guy in Maine and get it packagedup tomorrow and have a 2L modified and built by this weekend. So VERY busy this week. Give me a call and we will see what we can find. emoToast

 

[Nomad 1500]

Update on my motor noise. It turned out to be the lower unit. Wrenchin suggested I pull the drain plug & check for metal shavings. Sure enough it was full of them. New lower unit on order from SEI.

 

[wrechin2]

With all the facts you gave and it started acting up it reverse, it was pretty obvious. You gonna bring it over this weekend and tear it down?

 

[Nomad 1500]

I can't tomorrow, company picnic. I'll give you a call when. Thanks again.

 

[wrechin2]

Ok! Let me know!

 

[Nomad 1500]

I pulled the prop shaft and carrier and here's what I found.