Tip: hot days might not need to choke , , , easy to flood

My daughter called me early Mon that when she reached the lake after trailering her 25 merc 2 stroke turned over but would not start. I said you probably flooded it choking it and trying to start it after the 1 hour ride with a black motor housing and it was 9am and already 85 degrees out.
As luck would have it there was a guy at the launch from a local boat shop and he suggested to her to push the throttle all the way forward and then try it again as that de-floods the outboard. It worked! I wish I could have remembered that as it slipped my mind since my merc model has an automatic choke.

So remember on hot days you may not need to immediately apply the choke if your model has one. And if you flood it push the throttle handle all the way forward then crank it. She actually thought of that herself but thought the boat would possibly take off if it started with the throttle in the full forward position.

She also was not using her trailering cover, so I suggested she at least use the outboard cover to keep the sun off it. This also stops flying rocks off some trucks rear tires on the highway from chipping the housing

Re: Tip: hot days might not need to choke , , , easy to flood

IT also helps to disconnect the fuel line in hot weather.
With it connected, and the gas tank in the heat, the built up pressure goes out the hose into the motor.

I have a Johnson 15 that will flood out when trailered with the hose connected in warm weather. I'm guessing it is pushing gas past the needle valve.

Re: Tip: hot days might not need to choke , , , easy to flood

If that's a rebadged Tohatsu, 25/30 has different temp starting procedures. If picture matches it's rebadged, this proven formula works quite well. Check


Happy Boating

Re: Tip: hot days might not need to choke , , , easy to flood

Thanks for the posts. I passed along the tip to disconnect the hose from the outboard when trailering on hot days or when the trailerable cover is off. Can't hurt to try the disconnect tip.
sea rider: it's a 1998 electric start model. The rig is a 1998 Monarch which has a choke feature when you push the key in which is on the dash. I don't think that choke feature ever worked so she pulls it out manually on the o/b before starting. I had the merc shop put on an oem carb several years ago when she bought the rig used so as not to have starting issues down the road with a 10 year old rig at the time. Was not much more for a new carb rather than pay them labor to clean it. They also found a faulty electronic part that was causing stalling when idling like when slowly pulling into a launch area. Had to keep restarting it like 10 times. Runs like a brand new outboard past few years after the repairs. Runs as smooth as my merc 2007 40 hp efi.
After they showed her how to de-flood the o/b she had no further issues that day!