1984 15hp only tops out w/ half choke

[marshdonkey]

Had a problem with a rough running OB this spring and after a carb kit i was told it had a clean bill of health (never had prob before). The last few months it's run reliably but only with the choke pulled 1/2 way out. I've tried running a richer gas/oil mix but have noticed no change.
The engine will run with the choke "in" but will just flounder at full throttle and not even get my little 14' on plane.
Tried: Fresh gas(treated), new fuel lines & connections(to tank), new plugs, checked filter inside tank.
Any ideas appreciated.

 

[Daviet]

Re: 1984 15hp only tops out w/ half choke

Sounds like it might be time to remove and clean carb.

 

[Rick.]

Re: 1984 15hp only tops out w/ half choke

Agree with above. Sounds like your high speed circuit is in need of a good cleaning. Best of luck. Rick.

 

[Fuzzytbay]

Re: 1984 15hp only tops out w/ half choke

The last few months it's run reliably but only with the choke pulled 1/2 way out. I've tried running a richer gas/oil mix but have noticed no change.
The engine will run with the choke "in" but will just flounder at full throttle and not even get my little 14' on plane.

Chokeing the motor, is actually riching up the fuel mixture, by cutting off the
amount of air into the carb throat. You have a problem with the high speed circuit. Now when the carbs were rebuilt, were the welch plugs removed and the passages cleaned?

My other question is, did you have to start using the choke right after the carb rebuild? Or did it happen later on?

 

[marshdonkey]

Re: 1984 15hp only tops out w/ half choke

Sorry for the delay in replying......I've had 2 carb kits comleted in the last 4 years...the most recent was at the end of last season (Sept. 09).....I would say it took about 2 hours of runtime after the kit install I had to start half choking and then it came on pretty fast.....As I remember it started stalling out at high speed a few times and then BAM...I needed to half choke it to keep it running. If it makes any diff. I at low RPM it doesn't seem to matter much about the choke...the only way I can get the RPM's up enough to get up on plane is to get that choke in EXACTLY the right spot around halfway.
Thanks for any ideas.

 

[marshdonkey]

1984 15hp only tops out w/ half choke

bump

 

[Rick.]

Re: 1984 15hp only tops out w/ half choke

I really think you will find your carb. isn't clean but I understand why you think it is. I noticed you've replaced all the gas hose. Is that right from the tank to the carb.? When did you do it? Was it after the second carb. kit or before? Rick.

 

[marshdonkey]

Re: 1984 15hp only tops out w/ half choke

Yup...Everything has been replaced from the tank to the carb with all connections tight. Before my last carb kit was put in I couldn't keep it running unless I squirted gas directly into the carb...It would burn that and then die right out as soon as it was gone...wouldn't draw at all....I honestly thought it was the fuel pump or a clogged line but that was all checked. I thought there might be a pinhole in the line from the pump to the carb but that was replaced too. Running it in the tank you wouldn't know anything is wrong...just a little doggy....Pushing the boat though it just wont' wind up unless that choke is in just the right spot around 1/2 way out.
Thanks for your feedback....I hope I get it straightend out by October duck season!!!...LOL