1975 Evinrude 9.9 no start

[kalebg]

Okay so it seemed to be trying to run on 1 cylinder so i pulled the plug wire for #2 and got no change seemed to only be firing on cylinder #1. Compression is equal between both cylinders. Whats next?

 

[oldboat1]

3/8" spark should be fine. Seem to be dropping a cylinder, as you suggest. Use the spark tester on #2 again and see if you get spark. If so, clean up and regap plugs, or replace -- see if operation is better.

 

[BlackoutBill21]

the cylinder thats not firing... whats the plug look like? shiny? oilly? that cylinder is still showing spark at 3/8?

as the owner of a 9.9 that has never run correctly with the 15hp carb, do you have a 9.9 carb to test with?

i didnt see you changing the fuel pump for new. I bought a new fuel pump and after 1 use the inside cracked and fell apart.

then just double check your tank (vented) and fuel bulb. also make sure your choke plate is closing all the way

 

[tomhath]

Try swapping the spark plugs, they can go bad. Also try starting it in a dark location, you'll see if a wire is arcing.

 

[kalebg]

Spark plugs are brand new. I got a 4 pack though so ill try another on cylinder #2 as I noticed the top of the center electrode isnt flat and parallel to the spark plug body its slightly angled. The plug isnt soaked or oily at all.

 

[kalebg]

Sooooooo, I think I may have found the issue. And yes its due to my own dipshittery lol. So when I had the powerhead off I was removing the bottom seal gasket with a scotchbrite wheel. I was mindful that nothing made its way into the exhaust. So what did I do? Well natually I put some paper towel into the exhaust port. Yeahhhh so you see where im going. Sometime at 2am when my wife said to come in already I just threw it together real fast in a rush and next morning was "pretty sure" I remembered to remove it. Now im 99% sure i left it there. How do I know? Welllll it just spit a big chunk of soggy papertowel out the exhaust -_-

 

[tomhath]

Welllll it just spit a big chunk of soggy papertowel out the exhaust -_-

LOL. At least it wasn't a wrench.

 

[kalebg]

So its running now. Has a little issue idling, it needs a little pressure on the cam follower turns out it has a deep groove worn in it so it needs replaced. Otherwise only other thing to note is that I can hear an occasional miss so at idle its a little jerky. smooths out on the top end, but the occasional miss is still audible.

 

[oldboat1]

The plug terminal screws off and probably could be cross threaded (my first thought when you mentioned the electrode was angled.) It's possible, of course -- and more likely -- that the plug is cross threaded. You might back it out and carefully try to seat it straight, after making sue the terminal is screwed on tight.

 

[kalebg]

I meant the actual electrode tip not the plug terminal. Spark plug hole itself has nice clean threads no cross threading whatsoever. After swapping that plug it actually fired on both cylinders and I at least got it started

 

[flyingscott]

Have you put the correct plugs in yet?

 

[kalebg]

Ill get some NGK BR6HS ordered. Found Leroys site and saw it rerecorded them over the Champion UL81C for better trolling perfomance on the magneto setups

 

[kalebg]

Pulled plugs: rich af. New plugs swapped in obviously no difference. Played it by ear, leaned it out until the rpm went highest, leaned it 1/4 turn: rpms dropped, gave it almost 1/2 turn rich called it good enough. Been a few years since i had to touch a carb and my experiece is very limited (millennial and all) so I almost forgot how

 

[oldboat1]

Sounds offhand like you may have overcorrected a little too rich. I would go back to the highest rpm at the lean setting, throttle back to about 650 rpm, give or take, and test putting it into gear. If it goes into gear with no stumbling or stalling, I would say you found the right setting.

 

[kalebg]

From what I know the fastest RPM would be a slightly lean mix right? I only adjusted 1/4 turn back to start and like 1/8 turn richer should that be okay? Not sure how 2 strokes handle running lean, figuired they wouldnt like the heat since the fuel mix cools the pistons.

I will probably have to order a new fuel pump first. It seems this one is fading maybe? For the most time it worked. Primed, start, run. But one time after running I killed it I could see my fuel line to the carb was empty (I ran clear Tygon 4040-A fuel line). Half the time I restarted it i had to reprime. Or maybe my bulb is bad? Its a cheap Walmart attwood fuel line and the bulb has to be squeezed quickly to get it to go hard a normal or slow squeeze just does nothing?

Its not really a fan of idling around 600rpm. It runs for 30 sec and then you can hear it losing RPM s until it stalls out unless i rev it up by giving it a little throttle. Seems to have a min stable idle around 700-800 and went into gear fine

 

[racerone]

Fuel for high full throttle operation goes through the high speed jet ( orifice )------Not sure why you are adjusting the low speed mixture for a difference in high speed operation ?-----Look into issues with your carburetor / fuel pump / hose / bulb / pick up tube in the fuel tank.

 

[kalebg]

Fuel for high full throttle operation goes through the high speed jet ( orifice )------Not sure why you are adjusting the low speed mixture for a difference in high speed operation ?-----Look into issues with your carburetor / fuel pump / hose / bulb / pick up tube in the fuel tank.

At least pretend to read it all. CONTEXT. By fastest RPM im referring to setting the slow speed mix knob AT IDLE. It was running overly rich and i leaned it out without touching the throttle. This proper fuel mix resulted in a better burn increasing the power and thus increasing the engine rpms slightly. When I adjusted it overly lean the engine lost power quickly and rpms decreased so I turned it back. Knowing that slighty lean is the hottest burn and afraid of overheating the pistons with a possible lean burn I overcompensated by setting it 1/8 turn richer

 

[oldboat1]

Irrelevant. You can't hurt the engine by running a lean carb AIR/fuel mix (the engine will stall if too lean). The oil/gas mix is a different story.

You control the idle mix and the knob setting. When you get the proper mix, refit the knob half way between "rich" and "lean" so you have some room for possible adjustment when on the boat. But that's about it. You should not be regularly adjusting the carb AIR/fuel miix.

 

[kalebg]

Is detonation not an issue with outboards? Ive seen tons of 2 stroke bikes with meted or scored pistons from running lean so kind wary. After all its not a 4 stroke so the pistons dont have oil jets or splash from the oil bathed crank the premix is all that cools the pistons

 

[racerone]

Wait a minute.-----It is a 2 stroke and the piston is always coated in oil !!-----Has to be , to be lubricated while running at 5500 RPM all day long.