Step By Step timing For a 120 hp force

[usmc_hemb]

I have a 1997 force 120hp outboard, with a 95 block i believe. I just had rebuilt my engine not to long ago and had the timing off and melted a piston head. I have it all back together again but i want to make sure that i have the timing set exactly this time. I am not exactly sure how to do proper timing here so if anyone could give me some step by step instructions that would be awesome. Thanks all.

 

[john from md]

Re: Step By Step timing For a 120 hp force

First, let me know how many timing marks are on your fly wheel and if one mark is off set to the right of the others.

John

 

[usmc_hemb]

Re: Step By Step timing For a 120 hp force

There are a bunch of marks on the fly wheel it goes 40, 30, 20, 10, 0, 10, 20 with 4 tick marks in the middle of each. I believe it has to be set 28 degrees retarded.

 

[john from md]

Re: Step By Step timing For a 120 hp force

Follow me through.

The flywheel rotates clockwise so the first mark that you see that crosses the mark on the crankase would be the most advanced timing possible. In your case it is marked 40 degrees which would be 40 deg Before Top Dead Center BTDC. The last mark on the flywheel, which should be separated from the other marks will be the 0 or Top Dead Center TDC mark.

You want to set your timing at 28 or 30 degrees BTDC using the starter with the trottle at WOT. This will give you 30 or 32 degrees BTDC running at WOT. You will need to jumper the neutral safety switch to do this.

If your idle link and sync adjusment is correct, you will seel 0deg to -2deg using the starter with the trottle at neutral.

If you read 28 with the trottle at WOT, you were reading 28deg BTDC. You can leave it there or adjust the additional 2 degrees. Don't go any further as the gasohol we are using today does not have the anti-knock qualities that earlier gasoline did.

Since you had an earlier meltdown, best leave it at 28. Also, when adjusting your carbs, don't go below 1 turn out for the same reasons.

Did this help,

John

 

[usmc_hemb]

Re: Step By Step timing For a 120 hp force

Yes i got it timed at 28 degrees at wot and its running great. Thanks for all the help.

 

[jerryjerry05]

IF??? you adjusted it it's probably wrong(sorry)
​Usually they don't jump or move.

The actual wide open timing isn't done.
You need to do a static timing.
The top posts in this forum have procedures to static time the motor.

Since you have the Mercury ignition you need to remember 28 is the set point.

Now did you remove all the plugs and ground the plug wires?
Did you advance the throttle all the way?(you might need to tie it down?)
You use a jumper to turn the motor over?

Read the top posts or sticky's and get a factory manual.

Oh yea they don't like you opening the old posts.
You should start your own.
The mod's close these posts when they see them.

 

[gydatree]

Well I would've started a new thread but the questions seemed pretty simple.

I grounded all spark plug wires, dont think it had the safety switch as I didnt see one and it cranks with the throttle at WOT. I connected the timing light to number 1 and cranked it. I adjusted the screw under the trigger with the locking nut until i got it to 28, and it was running way to high.

Is there a different way to get it to WOT or something? Like by maybe disconnecting the throttle cable and moving the throttle levers to WOT manually?

Where it is set now sounds right, solid at low idles and WOT.