Where to Drill exhaust mod mercury outboard.
 

I've seen this topic covered a million times but have never seen a pic of one. not looking for performance just noise. Where exactly do I drill my lower unit to let some exhaust exit ? To make it louder . I'm not gonna go crazy and swiss cheese it just few small holes. It's a Merc 2.5L black max 175 . I only go on the Chesapeake Bay no rivers no lakes etc... So noise is no problem.i can tap and thread the holes as well if I don't like it. I also have a spare lower .please post a pic of where Exactly to drill. I'm not talking about taking the power head off and drilling the can etc... Talking about quick and easy drill the lower

you don't drill the lower, you drill the mid section, to do it right, you remove the powerhead, exhaust adapter, and the exhaust can. leave the can out, drill 6 1/2 holes from the top thru the bottom of the mid, exiting just above teh anti ventilation plate. Search on screamandfly.com for a detail write up. Heres a picture from the top
https://www.google.com/search?q=merc...d1GlKjM:&vet=1

There's another method.thr "idle relief mod" it can be done you drill through the lower. I've read a bunch of forums talking about it. Some one always says it can't be done and then 20 people say it can be done.

Also they sell a cover (Bob's). U drill it put the cover over it. The cover has plugs so u can tune or quiet it.i just need to know where to drill it

you still need to pull the can

Well I got screwed. My new to me motor is junk ..has a cracked case hidden by permatex. Runs like crap and spits water out side of block....

thats not good, where is the water leaking? have you done a compression test? spark check?

No I have not. But there's permatex I. Random spots on crank caske right above where it bolts up to mid. And it's blowing water out there .the motor is surging and wont idle or do snyrhi g below a few thousand rpms. It's deffinetly sucking air. The guy I bought it from said he'll gimme my money back as long as I return the motor (3.5hrs away)so I'm removing it and semdj g it back up north

U get it from an individual or an outboard rebuild shop, just wondering.

An individual. Bit he had a garage full of outboards n parts etc....days he didn't know about the crack........but must be stand up if he's gonna give me money back. Took old motor off this AM. We will see if he keeps his word