1990 force 120 wont start 10 min after running

[dariel17]

Re: 1990 force 120 wont start 10 min after running

I did the timing already. Is set to 28 deg at wot. So the cam screw is not supposed to touch engine block st all correct? Brcause if I adjust it wouldn't it throw it off timing due to is connected to the timing blocks on top by flywheel?

 

[Nordin]

Re: 1990 force 120 wont start 10 min after running

You set the throttle pickup point (exentric nylonroller at carb) with the throttleshaft diconnected.
The nylonroller shall touch/intersect the cam at the mark or between the marks if it has two marklines.
If it don?t lose the screw a bit and turn the roller so it touch the cam then secure the exentricscrew with the nut.

Then check the timing. Set the engine at WOT (with the remotecabels disconnected). Crank the engine with all plugs out and grounded, use a timinglight with pickup sensor and put it at #1 cyl. Point at flywheelsticker and the 28dgr mark shall line up with the blockpointer (reference). 28drg static timing will be 30drg running.
If the timing is off you adjust it at the screw at top of timing tower. This screw make the timingplate go less or futher (turning) make the timing to retared or advance.

Now check the carbbutterflies so they are horisontal at WOT. Put the throttleshaft back and set engine in WOT. If the butterflies not are horisontal adjust the throttleshaftlength by losing the stopnuts and turn the shaft, then secure the shaft with the stopnuts.

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Ok I will post some pictures today of how I have it then u tell me if its correct. Also my fuel filter does not stay full it stays kind of empty and u see a little fuel coming in as the motor runs.

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Can some one explain to me how I can post pictures on this thread?

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Any one?

 

[SkiDad]

Re: 1990 force 120 wont start 10 min after running

click on the 3rd to last icon and then browse to the folder on your computer that has the pictures. I'm not sure you can do it with a tablet or ipad - so try from a computer if you haven't. You may need to choose "Basic Uploader" after the screen opens

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

To post pics on this forum do the following:
With the icon menu from the top of the "Quick Reply" section, click the 3rd icon from the right. In fact, if you place your mouse on top of this icon a pop window will say "Insert Image". A pop up window will show up titled "Insert Image". From here you have two options where to get the source of the image. Usually I just load from my computer so I click "Computer". From here it gives you option to use either the "Select Files" or "Basic Uploader". Either will do. When you click either one button it will open another window showing your file directories. From here you will have to choose the pics you want to upload. For multiple pics, you will do multiple uploads. When you click "Upload" then the pics will start showing as URL links instead of the pics themselves. The pics will not be visible until you finally post or click the post quick reply.

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Sorry for posting them on 3 different posts but that was the only way it would let me upload them from my phone.

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

View attachment 224670

This photo tells me the idle screw (is not pushing against the engine block) is set at zero setting meaning the throttles on both carbs are fully closed. Which basically means the motor will not idle and probably would not start unless you put the control lever in fast idle.

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

View attachment 224671

This is the idle screw setting. After you set your timing at 28 BTDC, you need to set this so the motor idles around 800~900 in neutral or 750~850 in gear. After setting the idle, the alignment of the scribed lines on the cam and the slot of the eccentric bolt will NOT be aligned anymore, meaning the throttles are NOW opened a little bit to allow the motor to run at idle. And if you check the timing at this time, it will not be zero but somewhere ahead like 3~7 degrees. Remember when you set your timing it was at WOT meaning at closed throttles the timing is at zero degrees ahead.

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

Double post.

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

View attachment 224672

This is the timing adjustment. Usually you only touch this when you are setting your timing. After that you just leave it alone.

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Ok so once I set the timing on the top blocks I dont touch it no more?. But once I move the idle screw on bottom wouldnt it throw the timing off? Because once u push that throttle link rod bolt against the block the timing moves on top by the flywheel this is very confusing

 

[Jiggz]

Re: 1990 force 120 wont start 10 min after running

Ok so once I set the timing on the top blocks I dont touch it no more?. But once I move the idle screw on bottom wouldnt it throw the timing off? Because once u push that throttle link rod bolt against the block the timing moves on top by the flywheel this is very confusing

Moving the idle screw will not change the set timing at WOT. The engine timing is designed to move linearly with the throttle controls. Meaning if the throttles are at zero (meaning the idle screw or the throttle linkages also at zero or minimum with throttles closed) timing is also zero BTDC on #1 piston. Adjusting the idle set will move the throttle (opens the throttles) in linear with the timing, meaning as the throttle opens so does the timing advancing linearly until you open the throttles all the way at WOT and the timing will be at 30 degress BTDC (although in static this will register as 28 degrees). Static means the engine is not running. So do not confuse yourself just set as discussed and test the engine and let us know what happens.

 

[dariel17]

Re: 1990 force 120 wont start 10 min after running

Ok will do that now thanks really appreciate it.