Ford 460 starter problem??

[Elliomcmh]

I'm having some trouble with my Ford 460 in my jet boat. I had to repair the block and reassembled everything. Now engine barely cranks and will not start. I have attached a wiring diagram, so hopefully that helps. My battery is brand new and I have had the starter tested at Napa. The voltage at the coil was 6 volts even when trying to crank the engine.

The voltage at the "s" terminal on the starter is only 5.6 volts when I try to crank the engine. The voltage on the "i" germinal of the starter is 12 volts. Does anyone know what could cause this?

 

[Bondo]

Ayuh,.... Corroded, Bad wirin' connections,.....

Clean to shiny metal Clean both battery terminals, 'n the other end of those cables, 'n try it,.....

 

[Elliomcmh]

I have cleaned every terminal and contact point with a wire brush until it's clean are metal, didn't help. I'm stumped.

 

[Bondo]

Ayuh,.... It honestly sounds like a Bad Ground,....

Maybe try a set of jumper cables, 'n put both sides to the battery ground(-), 'n the other ends to the starter castin', block, or other ground points,.....

Also any wires or cables with nicks or cuts along it's casin' could weep in water, 'n corrode, passin' voltage, but not amperage,...

The voltage at the "s" terminal on the starter is only 5.6 volts when I try to crank the engine. The voltage on the "i" germinal of the starter is 12 volts. Does anyone know what could cause this?

Rereadin' this, I think ya need a slave solenoid, because the trip to the key switch, 'n back, is a major voltage loss,.....

Donno,...

 

[Scott Danforth]

are these new cables, or are these the existing old cables? you could have severely corroded cables within the insulation or the crimps.

Also, since you had to repair the block and re-assemble everything: did you paint the starter before bolting it on? did you paint the block prior to bolting on the ground cable? did you run the motor prior to installing in the boat?

 

[Elliomcmh]

I'll try bypassing the solenoid with a remote starter when I get home. I only painted the heads and intake manifold. And I tried an old cable and a new cable with the same results. I cleaned all of the terminals and contact points with a wire brush. It's the same motor, I just fixed the water jacket block crack with metal stitching and reassembled it, the engine ran fine before.

 

[Bondo]

I cleaned all of the terminals and contact points with a wire brush.

Ayuh,.... Includin' the battery's ground cable connection to the block,..??

 

[Elliomcmh]

Yes. Including that connection.

 

[Elliomcmh]

Rain delayed the voltage testing but here are the results. The boat fired up and I ran it for about ten minutes but then it wouldn't start again.

Coil voltage while engine is idling (leads on - and + on the coil) : 3-4 volts

Coil voltage while engine isn't running and key is in the run position (leads on the + and - on the coil): 5.72 volts

Resistor voltage with key in the run position (ground lead to battery): orange wire- 6.35 volts, purple wire 11.03 volts

"E" terminal on solenoid voltage (ground lead to battery)
Key in run position: 12.05 volts
Volts while cranking 12 but drops while cranking

"G" terminal volts while cranking 5.5-6.8

So it looks like the solenoid is getting the proper voltage but not transferring it to the starter???

 

[Bondo]

Coil voltage while engine is idling (leads on - and + on the coil) : 3-4 volts

Coil voltage while engine isn't running and key is in the run position (leads on the + and - on the coil): 5.72 volts

Ayuh,.... Those are not valid test points,....

Test coil voltage from the (+) terminal to Ground, not the other side of the coil, which feeds the points,......

So it looks like the solenoid is getting the proper voltage but not transferring it to the starter???

Ayuh,..... That's what I said in post #4,.....

 

[Elliomcmh]

So I went ahead and charged the battery to make sure my numbers are accurate, voltage at battery was 12.58

Difference in potential (E &G): 0.05-0.10 volts
Voltage at coil with key in the run position (ground lead to battery): 6.31 volts


Voltage at E with key in run position: 12.58
Voltage at E while cranking 12.58-9.24
Voltage at G while cranking 8.4-9.2
Voltage at battery while cranking 9.0-9.4


Orange resistor wire with key in run position 6.37
Purple resistor wire with key in run position 11.36

voltage measurement with lead on pos. battery terminal and lead on E: 0.26-0.17

Thank you for the help!!!