'93 25HP J25RETS tough starting cold

[tucker99]

Runs great once it's hot. Takes 10-15 min to get hot and sneezing the whole time. Bear to start cold. I think I'm doing something wrong with the start primer. I pull and push the primer knob twice. I then notice a lot of resistance on the primer knob, not sure why that happens. Put the throttle grip at about the 11:00 position. Takes about 5 or 6 crank sessions before it starts and then it stalls several times. My initial thinking is to turn the throttle screw CCW in 1/8 turn increments at wait for results. Any ideas?

 

[DaleH]

Try this! Pump primer bulb firm then pull the choke/primer knob OUT and leave it out whilst cranking. Once she catches and fires and then starts to bog, push the choke/primer knob IN. Sometimes if/when cold you might need to quickly pull it out again for a second or less.

 

[tucker99]

Thanks Dale, will do, pulling the primer knob OUT injects gas into the carb and intake, and leaving it out let's it trickle in correct?

 

[DaleH]

Thanks Dale, will do, pulling the primer knob OUT injects gas into the carb and intake, and leaving it out let's it trickle in correct?

Well, the Service Manual refers to it a 'manual primer' but the Operators Guide calls it a 'choke', probably as it is the knob on small OBs to help cold starting that we're all familiar with. Technically the difference is that a choke is usually a butterfly plate that closes the carb throat, thereby enriching the mixture by reducing air, thereby adding fuel for starting. Bigger OBs use electronic primers where they squirt when the key is ON and pushed IN (regardless if turned to crank). Manual primers, to the best of my knowledge, need the primer bulb pressurized firm and quite possibly the vacuum added by pulling the rope starter to help start the motor.

Regardless, the Operator's Guide for OMC 2-strokes says to pull it out and leave it out as the engine catches. When she starts to stumble/blubber as in too 'rich', push it in, where usually a cough or sneeze is indicative of a 'lean' condition and that means you need more 'choke'. Newer OBs don't seem to lood as much as older ones, but if you flood a 2-stroke, turn up the RPMs high in Neutral, choke closed, then pull or crank OB to clear and when she catches, back off the RPMs immediately!

By the way, I just sent this OMC Operator's Guide over to Jim to add to his library here: https://www.tinboats.net/manuals/ , so you can download it later whenever added.

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[RaisedByWolves]

Runs great once it's hot. Takes 10-15 min to get hot and sneezing the whole time. Bear to start cold. I think I'm doing something wrong with the start primer. I pull and push the primer knob twice. I then notice a lot of resistance on the primer knob, not sure why that happens. Put the throttle grip at about the 11:00 position. Takes about 5 or 6 crank sessions before it starts and then it stalls several times. My initial thinking is to turn the throttle screw CCW in 1/8 turn increments at wait for results. Any ideas?

If your getting resistance with the primer knob you might have a plugged primer nipple.

That would account for the stiffness of the knob, the hard start and possibly the lean condition until warm.

I pump mine twice then pull it out half way and leave it there until warm.

Starts on 2nd pull.