120 Force 1996 20 amp fuse blowing

[Neil Walton]

OK here goes nothing!

So I have a 1996 Force 120, rebuilt by a shop, bought last year. Runs great except, when I power up to 2/3 to 3/4 throttle the 20 amp fuse blows. What I see. Voltmeter on the dash goes above 15v, Tach is not working. If I keep the RPM low it seems to run fine and does not blow the fuse.

Changed regulator 3 times now with CDI and OEM regulator. Now what it does is regulate to 12v and when I operate the power tilt and trim it shows a discharge on the voltmeter. Blows the fuse at 2/3 throttle.

I have done all of the bench testing I can and seem to get all the correct readings.

The only thing I have done is, the power tilt and trim switch that came on the handle broke so I rewired a secondary switch in. Switch works fine.

 

[legalfee]

What kind of DVA readings are you getting? Is anything hooked to the red wire coming from the fuse besides the ignition switch?

 

[Neil Walton]

Ill get back to you tomorrow. Raining like hell all day today!

 

[pnwboat]

When you say the 20 amp fuse blows, what does this fuse supply voltage to? Is it the gauges? If so, you might have an issue with one of your gauges. Maybe the Tach, since it doesn't work?

 

[Neil Walton]

it supplies power to the starter and everything

 

[legalfee]

Here is the wiring diagram. Wire from fuse is going to tilt trim and ignition switch. Isolate them and you should have the culprit. The red wire also goes to the regulator / rectifier.

 

[Jiggz]

Try isolating the problem first by disconnecting the the yellow wires from the regulator. Since you think this is engine speed related, this will isolate the charging system from the fuse. If the fuse blows still then the problem is NOT with the charging system.

Also the gray wire off the regulator is the input signal wire for the tach. If the tach is shorted inside, it can also blow the fuse as it's internal power is fed from the ignition switch. You might want to isolate this wire also (and yes it is speed related although isolating the yellow wires basically isolates the input signal too) to see if the fuse will stop from blowing.