won't rev past 2500 rpm!???
 

Looking for some help!!!

my 1996 5.7 merc won't rev past 2500 when in gear.
in neutral it revs as normal, no hesitation up to 5000rpm.

it bogs from the get go and then quickly jumps to 2500 and stays there.

I was heading back to the dock at my max 2500 rpm and after 1 minute, the engine slowly started to rev higher and took off as if nothing was wrong. After about 2-3 minutes it bogged back down to 2500 again.

In neutral... no problems..
in gear... fubar!

any suggestions?

Sounds like a drive problem......

Brian

Sounds like a Fuel Delivery Problem. My Boat had the same symptom's. I would check the Fuel Filters, if nothing there then check the Fuel Pump. If that doesn't't fix you might look at your tank. My Problem was the fine Stainless Screen in the Fuel Tank.

I agree with High Maintenance, it sounds like a fuel problem, probably the pump is not putting out enough volume under a load.

thanks for the suggestion about the fuel system,
I'm hoping to look at it tonight.....

will post the results!

I have experienced a simular condition that took me a long time to diagnose. It was a poor electrical connection/low voltage to the pos side of the coil.

It's an easy test. With a volt meter, check the voltage at the pos side of the coil. I used a jump wire from the bat and performance retuned to normal. Ended up replacing several connectors before curing the prob.

Hope that helps,
Andrew