1985 Mercury 35 hp only stays running with choke.

[mmumm]

I just got my boat pulled out after I had it put away for winter and I took the carb off so I could clean it and put a carb kit in it. I did that and put carb back on today and I get it to run with choke on and it also stays running pretty good. I let it warm up for around 5 minutes a few times but when I turn choke off it runs for about 5 seconds and dies. I also put brand new spark plugs in it. It ran fine before I put it away before winter. I did not put fuel stabilizer in the tank and I'm wondering if this could be the problem, maybe just bad fuel? Any ideas?

 

[ondarvr]

The carb is still dirty.

 

[Chinewalker]

I agree, carb is dirty. Could be fuel related - if you have garbage in the fuel, clean the carb, and then run more garbage fuel into it, then you haven't accomplished much. Remove the fuel fitting from your tank's hose and prime a half pint or so into a clean coffee can. Note whether it smells like gas. It will be apparent if it has gone bad - it will smell like varnish. Look for dirt, crud, water, etc. in the fuel. Once you've determined whether the fuel is good or bad, then clean the carb again. Thoughly disassemble it, clean it, take care to blow out all passages, jets, etc. Also, when reassembling, make sure the idle speed needle is at about 1.5-2 turns out from closed. Then adjust to best idle with the motor on the boat, in gear.

 

[GA_Boater]

All good advice in the earlier posts.

Adding to Chinewalkers advice - Do the final idle needle adjustment with the motor in the lake. Doing the adjust on muffs doesn't have the needed exhaust back pressure.

 

[mmumm]

Well I left it alone over night and it did same thing when I tried to start it just a little bit ago so I took the fitting off the front of the motor and shot some fuel out of it and the fuel looked good and smelled fine. I put the fitting back on, primed it and it started right up and ran like a top. No idea what was wrong, but runs good now.