Power Loss Bogging Down around 3500 RPMS

[tomfsu]

I have a 2002 Merc 125hp 2+2 carb system. When I get around 3500 RPMs the engine starts to chugg and I have to push the throtle up and I can sometimes catch it. When I am on plane the RPMs seem to bouce around alot unless I am WOT. If I am at WOT it usually runs o.k. Otherwise it will stall out completely. Please let me know what you think it may be. I recently had the Carbs rebuilt, but I am questioning if it was done properly.

Thanks,

Tom

 

[CharlieB]

Re: Power Loss Bogging Down around 3500 RPMS

The 2+2 system has been used for quite some time now and once set correctly works well.

Invest in a service manual and a few simple tools.

a compression testor, spark plug wrench, and remote starter button.
Ensure compression is fairly even, within 10% or less between all cyl's.

an adjustable spark tester.
Good spark on all cyl's

a couple of screwdrivers.
Adj carb linkage, idle mixture and accelerator pump to the letter, as spelled out in the factory manual.

 

[Searay 150merc]

Re: Power Loss Bogging Down around 3500 RPMS

You may still have dirt in the carbs. Had to take mine apart twice and clean before it ran right