Blowing 10a starter fuse

[ItsMyGirlfriendsBike]

Did some work to the lesser Hawk today, (fuel tank stuff) and when I tried to start it I blew the 10a ignition fuse. Replaced, hit the starter button, a couple of cycles and it pops again. Should I be inspecting the starter motor?

Thanks in advance.

[ItsMyGirlfriendsBike]

Also, before this issue, it was cranking fine but not starting. Shot a little carb cleaner at the pods and it wanted to fire. Looked at jumping the fuel pump, and wasn't getting a response. I wonder if the fuel pump has issues, will it blow this fuse?

[ItsMyGirlfriendsBike]

I may need to cross post this to the "I can't believe I did that" section.

I unplugged the fuel pump and it cranks/starts just fine (with a fresh fuse) until it runs out of gas in the carbs. Plug in the fuel pump and it immediately pops the fuse and dies. I must have hurt the pump with my attempt at hotwiring the pump.

Learn from my stupidity.

[ParcNHawk]

Try removing the relay. Then join the two black wires (one will have a blue stripe) in the relay connector. Leave the relay out of the equation.

[ItsMyGirlfriendsBike]

Bypassed the relay as prescribed by the factory service manual, no action from the pump. I assume this indicates that I managed to damage the pump with my ham fisted mechanical attempts.

[squirrelman]

yes, a bad pump can short to ground..................and blow a fuse. avoid any cheap $15 chinese replacement.

[ParcNHawk]

Is the pump still blowing a fuse? Or just not pumping?

[ItsMyGirlfriendsBike]

Here's a question- looking at the service manual, the fuel pump relay is also referred to as a shut off... Is it a tip sensor of some sort?

[ItsMyGirlfriendsBike]

Is the pump still blowing a fuse? Or just not pumping?

Yes, fuse pops when starter button depressed.

[ItsMyGirlfriendsBike]

Also, not pumping.

[ParcNHawk]

The fuel pump relay is not a tip over switch. It protects the ecu from the pump. It is intended to only pump fuel when the engine is turning... so if you crash AND the motor stops, it doesn't dump fuel all over.

Now the pump does NOT always pump with the engine running. The pump itself has a pressure sensitive shut off. When the float bowls are full then the float valves close. With the float valves closed there is no path for the fuel to go; so I'd the fuel pump strokes, it pressurizes a blocked off fuel line and stops pumping. This is all built into the fuel pump.

If you are trying to diagnose a dead fuel pump that is plumbed to full carburetors then it might appear faulty.

Next point:

If you unplug the fuel pump relay and the fuse blows then the problem isn't the fuel pump.

[Crash_Override]

I believe one terminal is your coil (+) and common which are linked internally. One is your ground/neutral one is your normally open. I may be wrong but I’m having electrical issues myself and that’s what I figured in my dicking around.

[ItsMyGirlfriendsBike]

I appreciate all the help. Fuse blows when cranking with fuel pump connected. With fuel pump disconnected, cranks fine and fuse survives. Carbs are empty, so don't know if the fuse would blow if pump was reconnected while running, but so far indication is fuel pump being the problem.


Here's the new issue: I ordered a cheap pump. I know, I know.

I went out to the bike, and plugged in the new pump, key off. Immediately wires start melting and smoking. I quickly yank the new pump free, but imagine wires on the bike to be damaged. Next step is to trace damaged wires and assess damages and what will be required to repair/replace.
I am a little confused with this, as I wouldn't think any power would be available with the key off. The bike is pretty rough, but everything seems to be in place with no obvious hacking of the wiring, though I suppose that's about to change.

I'm imagining needing to create a new fuel pump electrical circuit, but somewhat as a last resort.

[ParcNHawk]

The pump should not be getting power with the key off. Nothing should.

[6]

I appreciate all the help. Fuse blows when cranking with fuel pump connected. With fuel pump disconnected, cranks fine and fuse survives. Carbs are empty, so don't know if the fuse would blow if pump was reconnected while running, but so far indication is fuel pump being the problem.


Here's the new issue: I ordered a cheap pump. I know, I know.

I went out to the bike, and plugged in the new pump, key off. Immediately wires start melting and smoking. I quickly yank the new pump free, but imagine wires on the bike to be damaged. Next step is to trace damaged wires and assess damages and what will be required to repair/replace.
I am a little confused with this, as I wouldn't think any power would be available with the key off. The bike is pretty rough, but everything seems to be in place with no obvious hacking of the wiring, though I suppose that's about to change.

I'm imagining needing to create a new fuel pump electrical circuit, but somewhat as a last resort.

Sounds like you are at a cross roads man. Either break out the diagram, a meter and a razor blade... Or, get some wire out run yourself a new circuit.