150 Pro XS

My son has a 150 Pro XS model115037PHY, SN 1B803381. It hasn't been run above idle in a couple years except to load on the trailer. Today it came right up on plane and ran a little rough the first few minutes. It ran perfect after that till we started back in,then it would drop to idle speed,idle for a few minutes then would come right up on plane run a little ways then go back to idle speed again. we finally got back to the ramp like that. no alarms any time. I'm thinking fuel filter but not sure.

Moving thread to the 2.5L Forum.

Any warning horns occurring?

Wise to make sure it is up to date on ALL recommended ANNUAL Maintenance:


Recommended Annual Maintenance for Optimax Engines

A good starting point would be the Fuel Lines, Bulb, Fuel Filter and Pulse Pump (all at one time- see the FAQ Section):

FUEL LINES AND PERFORMANCE PROBLEMS

Thanks for moving, II didn't notice all the different Merc threads

No warning horns. I'll get started on the other things. Thanks

Ok so I drained fuel tank and replaced the fuel filter, put in 20 gal of fresh fuel and added 6 oz of merc quickleen. I noticed the horn didn't sound at startup so I replaced it. $44 pricey little bugger. I started on muffs and ran a few minutes and alarm sounded head temp was 211. I hooked the hose up to the flusher and it was fine head temp was 142. Problem is I get a constant alarm at 2000 rpm in neutral .

Biggest problem is that your water pump will require replacement. This should be done before running the engine again- 211 is "smoking" hot for that engine.

Warning at 2K RPM's in neutral is not supposed to happen (as you are not supposed to accelerate the engine unless it is IN GEAR, in the water and going somewhere (never attempt to rev in neutral).

Ok thanks

Replaced water pump and all is well. Thanks for the help.