Wont start, 1987 Force 85 HP (US Marine) model 856F7B

[eagle787]

I just bought this outboard. It did start and ran for a few minutes, shut it off and bought it. Took it home and a few weeks latter I tried to start it and "Nothing" its not firing at all. I was pressing the key /choke while cranking, had it in Neutral/fast idle water hose/muffs on, motor Trim about 90 degrees, or straight down. I primed bulb, good fresh 50:1 fuel mix, gas is at the carburetor bowls
I do have Spark at all 3ea. spark plugs. I sprayed Fuel/oil directly into the carburetor throats while cranking the
motor. It did not even "POP" silent no start condition. I did a compression test throttle plates fully open, Dry was at 100 psi
WET, All 3 CYL are at 105 p.s.i..... which i know it S/B around 140 - 150 but it's stone cold and has not ran awhile.
main thing in my option is that CYL are all equal @ 105. Any help at all on this would be greatly appreciated.
My back ground is auto mechanic in the 80's, aircraft mechanic for the last 30 years. I do not know too much about outboards, Thanks
2-stroke or 4-stroke...1987 Force 85 HP (US Marine) model 856F7B

 

[jerryjerry05]

2 stroke so it needs fuel/oil mixed at 50-1

The comp results are probably from the gauge.
The good is all 3 are real close..
But!! do another test with a different tester.
The equipment sold these days can be pretty bad.
Harbor Freight gauges is a prime example.

Not starting,
Since it fired and ran the first time and now NOTHING!!
First thing I'd check is the flywheel key.
Remove the plugs, insert a screwey in the top hole.
Turn the motor over (by hand) until the screwey is pushed out as far as it will go.
Then around the front of the motor, check the indicator above the top carb.
It should align with the single hash mark on the flywheel. That's TDC top dead center.
Should be close.

Sometimes the magnet on the flywheel lets loose and just spins with the wheel.
Check that?

Those check OK,
Then try tilting the motor up and trying to start it then.
Some reason it helps with the fuel flow??
If it fires,pops starts, shut it down and then lower and try to start.

 

[Tassie 1]

And also re- check spark.

 

[jerryjerry05]

Said he had spark on all 3

 

[Tassie 1]

That's why l suggested re- checking it.
it won't hurt to do it again.

 

[eagle787]

I'll have time to do those checks this evening. i work 3rd shift. Harbor Freight gauge is exactly what i used, i agree there crappy tools. Great advice from you all. i will check flywheel Alignment mark, re-check spark maybe even get new plugs??
Tilt motor and try to find that sweet spot. Hopefully it will be a sheared woodruff key, easy fix
I'm thinking if the magnet common to flywheel is loose time for a new flywheel but lets do it step by step.
Thanks I get back with results

 

[The Force power]

edit

 

[eagle787]

Timing marks are good, #1 CYL @ TDC Fyl wheel singal mark lines up with singal mark on top carb .
i rechecked my spark checked good. Hooked up my ear muffs/water on...squirted some fuel/oil mix into spark plug holes, all 3. Put plugs back in primed my bulb had shifter in neutral. Cranked it over it popped a few times, then ran had water coming out of holes. Warmed up motor and backed it down to a perfect idle... She's a keeper... I believe it may have been flooded when I sprayed fuel in carbs and that's why I had nothing not even a pop. And your correct about trim angle and having throutle half way I think my Force is very finkiky on cold starts. Thanks you for the help, advice and for being there to help me out.

 

[jerryjerry05]

Had Forces for over 25 years.
99% of the time they were great motors.
Then things like salt water and transom clamps and corrosion took over