How much RPM is too much

[Loxboy1]

I have a 96 merc 3.0l 225 with 610hrs, on my flats boat, 106-110psi accross all 6 cylinders. The sticker shows 5800rpms. But last weekend i was running the boat messing around and had brough it up to around 6200 and man she was running sweet. How far can you run this motor before a rod comes through the block lol

[pappa pete]

Your pushing it at that rpm, the extra rpm was probably the rev limiter richening up the fuel , 3L dont like high rpms

[XstreamVking]

6201 rpm is the breaking point.

[pearlriverrat]

..., or your tach could be off, and you just now got it up to where it needs to run.

[Loxboy1]

..., or your tach could be off, and you just now got it up to where it needs to run.

It runs great at 5600-5900 i was just jacking on the jack plate and the trim when i hit 6200. Prop is wrong, too small. Im going to start prop testing i was just wondering how much is too much so i know for when im testing. My motor is mounted as low as it can on my bobs 6” jack plate. With the plate all the way down and very minimal trim, not even enough to lift the bow i can hit 5700. I guess ill just shoot to be around 5800 then lol

[Chaz]

If you enjoy kickin the bones out on "wind em up -Wednesday" ! :eek:

We run a special , "Throw the rod to the holes - Thursday" ! ;)


https://i.imgur.com/tG6KE9ol.jpg

[pappa pete]

They do flash ECU but that dont change the fact the internals wont stay together at high rpms

[donmac]

pulling the cowls was kind of like scratching a lottery ticket,did I win or lose! It always amazed me the shrapnel was contained!

[mikej]

I spin my 3.0's 6200 every trip for miles...…..Let it eat!

[Chaz]

pulling the cowls was kind of like scratching a lottery ticket,did I win or lose! It always amazed me the shrapnel was contained!

It's like sweepin up broken glass .... :eek:

https://i.imgur.com/Ryp6jEAl.jpg

https://i.imgur.com/LXmwuC0l.jpg

https://i.imgur.com/0ygAvMnl.jpg

[jerremy powery]

Those are some amazing paper weight's Chaz!! Those 3.0L mercs sure do a nice job when they come apart thought it was only the 3.0 omc's that liked going from v-6 to v-4 in short order....:cheers:

[donmac]

the rod in the tank looks like it could have escaped the cowl had it been traveling in the right direction

[Dave S]

Glass reeds and plastic tanks make Rods go BOOM ?????? 7 liter and bigger 7000 rpms.... no reeds last????