3297 mariner exhaust

[Jjwyc]

Does a body know if this exhaust nozzle is a factory set up? I have 260 mercs with 4” to 3” exhaust hose on-each manifold they run to mufflers then out the transom to these nozzles that direct the exhaust into the water. Im only making 3000 rpm and am wondering if this is causing excess back pressure. I have gone through fuel system. Carbs and timing.
Thanks
JJ

[buster53]

I would look at props first. Any chance you are grossly overpropped.

[Jjwyc]

Props are good

[RGrew176]

I've seen that style of exhaust on several other boats so I think it is a normal type of exhaust.

[bud37]

Those are.....Davis thru hull exhaust....had em on our 28 Mariner....should be no problems there.

[Jjwyc]

Thank you. Just the answers I was looking for.
JJ

[buster53]

Qr Bbpost Props are good

Are they the right size? Too much pitch can kill RPM's.

[Viper]

Those are original factory exhaust equipment/option.