Force 150hp Won't Start

[mav6759]

1989 Ford F 150 horsepower good compression good spark getting fuel will not start don't want to even sound like it wants to start want to know if there's a safety switch on the motor somewhere because I'm trying to starr the motor without the controls double checked Spark Fuel and compression not even a bump or if anyone have any idea as to why it's not starting or even sounding like it wants to start please throw any ideas at me

 

[pnwboat]

Need to know if you have the Prestolite ignition system with the light blue coils and CD modules, or the Thunder bolt ignition system with the dark blue (almost black) coils and Switch Box ignition module.

What were your compression readings?

 

[SkiDad]

check out www.outboardignition.com - go to Force / then Stator and/or Power Packs for troubleshooting PDFs

 

[mav6759]

I have the light blue coil packs

 

[Jiggz]

You've got the Prestolite ignition system. Assuming your initial checks were accurate, i.e. good spark, compression and fuel. Double check make sure you get fuel into the cylinders by doing the paper test. That means remove one plug at a time and hold a piece of letter sized paper infront of the plug hole 3~ 4 inches. Crank it over and you should see fuel spray on to the paper.

If you are getting fuel into the cylinder, the next thing to do is to validate the timing to make sure you did not shear the flywheel key. If timing is correct that motor should start and ran. There is a video on the sticky post on how to do timing checks.

 

[jerryjerry05]

Pull the top plug.
​Insert screwdriver in the hole.
Rotate by hand until the screwey is pushed out as far as it can go.
Then above the top carb is a timing mark.
It should align with the single hash mark on the flywheel.
I believe the 150 used Prestolite until 91 then started using Mercury on some motors.

 

[mav6759]

Thanks for all the replies,So what you are saying timing will cause the motor not to start even though I'm getting fuel, spark, and have good compression. My question is won't timing through something off either the fuel or spark,

 

[Jiggz]

You can keep trying to start the motor with what you have right now. But when you finally decide it doesn't work then you can check on the timing to make sure the flywheel key was not sheared. AND YES, WITH TIMING OFF YOU CAN NEVER GET THIS MOTOR TO START AND MAYBE NOT EVEN TO COUGH, DEPENDING HOW OFF YOU ARE WITH YOUR TIMING! Of course this is not all 100% true but maybe close to 99.99% true.

 

[jerryjerry05]

The flywheel controls the firing as it turns.

Went fishing and got ready to start in.
​The stbd. motor wouldn't start no matter what I did.
Limped back in on the second motor.
This was a NEW boat at the time and I had just started working on boats.
I checked this and that and finally the boss suggested I look at the flywheel key.
That fixed it.

I did NOTHING different. Just shut it down and it wouldn't start????????

 

[mav6759]

Thank you for your reply, but maybe I'm losing something If I'm getting fire and timing control fire...how is the timing off...

Mav6759

 

[Nordin]

Do the test as jerryjerry suggest to check the flywheel position when #1 piston is at TDC.
This will confirm if flywheelkey is shared or not.

The ignition system will create spark if key is shared depending on how far the flywheel moved from it`s right position.
Too far may end up with no spark BUT if it moved just a couple of degrees it will create spark BUT NOT START.

 

[jerryjerry05]

The key in the flywheel keeps the timing where it's supposed to be.
​If you shear the key the wheel keeps firing the plugs but at the wrong time.
The fly wheel has 2 sets of magnets.
One on the outer ring of the inside of the wheel. This helps charge the ignition/ battery.
The other a smaller set in the hub. This is what fires the trigger as it spins.
The key shears and the inner set still fires but the firing may be 180d out or 45d out.
Depending on where the keyway ended up.

Just do that simple test I described.
The magnet should have 2 sets of hash or timing marks.
One is a series of 3 marks the other is a single line used for finding TDC.