1990 force 120hp hard start/no start

DukeDelago

Seaman Apprentice
Joined
Jul 17, 2009
Messages
46
Hi guys! Looking for some help here. I have a 1990 maxum 2100 LDC (l-drive) 120hp. It sat for a couple of months without running and when I went to start it up on the hose it did not want to fire up. The battery is fully charged and the motor turns over wonderfully (around 500 rpm) but I'm not getting any combustion at all. I bypassed the kill switch completely and used a cheap in-line spark tester to confirm that all four cylinders are getting spark. Compression test gave readings of 125, 125, 125, and 155 on 1,2,3,4 respectively (I don't recall the compression ever being that high in #4 but I tested 3 times and got the same reading.) If I crank it with the plugs out (and using the kill switch of course) I can see and smell the fuel coming out of the plug holes. Before starting any of these tests I was able to get the motor started after 15 minutes of trying and it ran fine for 20 minutes. I shut it down and tried to restart 10 minutes later and got nothing, not even a little "pop". My next step was going to be checking the timing but wanted to see if anyone had any suggestions or info to point me in the right direction. I have the original factory shop manual and am very familiar with this motor overall but I am stumped and don't know what to do besides systematically going through the entire ignition system. Please help as I would much rather spend my spare time on the water rather than in my driveway!!!!!!! Thank you in advance
 

DukeDelago

Seaman Apprentice
Joined
Jul 17, 2009
Messages
46
Re: 1990 force 120hp hard start/no start

Usually fires right up if I have the throttle in fast-idle and use the choke. The choke solenoid is operational. It sometimes takes a couple of tries if it has been sitting for a while for the fuel line to prime, but in this case I actually did manage to start the motor and get it to operating temp. even with the engine warm I am back to getting zero combustion and haven't been able to start it since.
 

foodfisher

Captain
Joined
Feb 18, 2009
Messages
3,756
Re: 1990 force 120hp hard start/no start

If you've got compression, spark, and fuel (are you squeezing the bulb till hard?), all I can think of is timing. Broken adjustment linkage or sheared flywheel key.
 

DukeDelago

Seaman Apprentice
Joined
Jul 17, 2009
Messages
46
Re: 1990 force 120hp hard start/no start

Timing was my next thought as well, although I hadn't considered the flywheel key as the cause. That would actually make a lot of sense. Thanks for the feedback, if the timing light tells me it's out of time I'll bet that's exactly the problem. I will check it out this weekend and post the results either way. Thanks again!!!
 
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