1986 Mercury 9.9 2-stroke - hard cold start?

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zuren

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I pulled my 14' Smokercraft with 9.9 Merc 2-stroke out of the barn to run the engine for the first time this spring. I acquired this boat last fall from my father who took excellent care of the entire rig. I wasn't in a position to spend a lot of time with the boat/engine last fall (new baby), so I did a hasty winterization and put it away. I'm wondering if I burned myself...

On my first go with the boat in the yard and engine in a 50 gal. garbage can of water, I noticed that the fuel line and priming bulb were hard as a rock (age). I tried squeezing and seeing if the engine would start, but got nothing. I figured my issue was fuel delivery, so I ordered and installed a new Evinrude brand fuel line with bulb.

Today, I pumped up the bulb until it was firm, choked the motor, and proceeded to wear blisters on my hand from pulling so much. After a lot of messing around, I finally pulled with one hand while holding the throttle plate open with the other hand, and the motor roared to life. I ran it for a long time to pull new, ethanol-free fuel and some cleaner into the carb.

This morning, I went back out and the same deal - impossible to start, and didn't have time to remove the cowling.

Once the engine is running and warm, it will start with barely half a pull and idles well. But when the engine is fully cold, all it will do is sputter and cough unless I do the throttle plate trick. I have not sprayed it with carb cleaner yet but wanted to get any additional tips/tricks that may help get this running right WITHOUT taking off the carb. If I have to pull the carb, I may consider the 15HP carb to boost output.

Thanks!
 
Are you advancing the throttle BEFORE you start it? He may have used it for trilling and backed off the throttle adjustment. I’d also close the choke or out to 1/2-choke, if it can be, after the first 2 or 3 cold pulls, as it sounds like you’re flooding it.

Tip - Try pulling it slowly a few times ‘before’ pulling the choke or advancing the throttle. And 1st thing I always check for hard starting is a proper plug gap.

The recipe for flooded OBs is to close choke & start at highest RPMS, just be ready to immediately back off the throttle.
 
DaleH said:
Are you advancing the throttle BEFORE you start it? He may have used it for trilling and backed off the throttle adjustment. I’d also close the choke or out to 1/2-choke, if it can be, after the first 2 or 3 cold pulls, as it sounds like you’re flooding it.

Tip - Try pulling it slowly a few times ‘before’ pulling the choke or advancing the throttle. And 1st thing I always check for hard starting is a proper plug gap.

The recipe for flooded OBs is to close choke & start at highest RPMS, just be ready to immediately back off the throttle.

I'll give this all a try; it may be my technique. This motor only starts in Neutral, and there is no throttle adjustment in Neutral, only the Idle adjustment, which is supposed to be set on "fast idle" at start.

Me advancing the throttle was only possible by removing the cowling and grabbing the mechanism by hand...definitely not as the engineers intended. I'm feathering it by hand AS the engine starts to sputter, and is allowing it to start and run.

I will double-check the gap. I pulled them to see if fuel was getting to the cylinder but didn't have a gauge.
 
Those older Mercs are notorious for that. The problem I ran across was those darn surface gap plugs. When the motor cools off, condensation forms on the plugs and the engine just won't start. Next time pull the plugs, wipe them on a dry rag, put them back in, and see if it starts.
 
It looks like I may have my hard start sorted out, thanks to the suggestions here...

So yesterday, I went out, choked the motor, pulled 2-3 times, unchoked it, pulled another time or 2, and it stammered and struggled but started then smoothed out and ran fine. I gave it a few shots of carb cleaner and left it to run for a long time, continuing to pull fresh fuel mixed with Seafoam.

At lunch today (I work from home), I tried DaleH's suggestion to do the slow pulls before choking. I didn't touch the choke and did 1 slow pull. On the 2nd slow pull, it was running before I had the cord 1/3 out of the engine.

So maybe I need to refine my winterizing procedure and/or my starting process. I'm waiting for the engine to fully cool to see if I can duplicate the result.

Prior to yesterday, when I had it running, the amount of black nastiness getting blown out of the exhaust seemed excessive. Maybe that was a function of me flooding the engine, or maybe the Seafoam is working? I topped up my water barrel, letting the gunk on top overflow. The last 2 runs did not produce nearly the amount of gunk, so I think I can sleep better knowing that I'm not blowing that level of pollution into my local lakes. I'm still going to save my pennies for a 4-stroke.

Thanks for the help!
 

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