1986 Force 125hp

[keepfishin]

When I start my engine out of the water with muffs and a hose, the engine starts and runs in idle without a problem. For some reason, when I try to start the engine while the boat is in the water I can't get it started without constantly having to squeeze the primer bulb. Once it is started, I have to put it in gear or the engine cuts off seconds after it starts. Anyone know why I can't seem to idle my engine while my boat is in the water? I thought it may be a fuel pump issue but wouldn't a bad fuel pump keep it from running at all? Maybe a carburetor issue?

This is my first large outboard and my first post on iboats, i'd appreciate any help I can get with this one. Thanks!

[bentle]

Press in on key while starting will engage the choke solenoid thus choking carbs. Check and make sure choke solenoid is working and make sure that both butterflies close and open properly. You should only need to prime up squeezey until firm then choke and turn over at the same time. Don't over do it with the choke or you will flood. If squeezey doesn't stay firm then replace it. Check all fuel line connections from tank to carbs for loose fit or cracked lines. Fuel pump diaphragm could be weak
it even have a pin hole and work well enough to get it started. Do a compression check on all four cylinders because the fuel pump will not pump enough fuel without
enough crank compression. Most motors will start very easily out of water but in the water there is more back pressure at the exhaust outlet or load.

[keepfishin]

Thanks for the suggestions! I'm gonna try to take a look at it this weekend, I'll let you know what I find.

[Jiggz]

I had the same problem. Ultimately, I found the cause to be a leaky idle exhaust port boot. Replaced it and everything is fine.

[keepfishin]

yesterday i checked the fuel lines from tank to carb. i squeezed the bulb to see if i could here where it was leaking and i found that air was being squeezed out somewhere on the top carb. it might actually be the same problem you mentioned Jiggz, was that pretty easy to fix? i'm a little nervous about tearing into the carb any suggestions?
responses have been really helpful so far thanks guys!