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8N loss of power

N

NJMark

New User
Owned a 51 8N for 40+ years. Recently, I installed a Pertonix ignition system on my 12V upgrade. It started fine but I noticed an oil leak by the external oil filter. While replacing the fitting to close off the leak, I touched the oil line to the solenoid's back terminal next to the block. This caused a loud spark. After fixing the oil leak, the tractor will not start. No spark at the coil or plugs. Voltage from the ignition key to the terminal block reads 2.5 volts? Any ideas what I did and how to fix it? Thanks.
 
Sounds like you popped the switch element in the Pertronix. Was it a Pertronix II or a Pertronix I? The P I's are a little tougher. A P II can fry itself in a car if you leave the key on without the motor running if the magnet is telling the switch to activate. Put your points back in and see if that fixes it. If so you know the culprit.
 
(reply to post at 09:13:25 05/27/22) Don't know which one it is. Petronix sent me a 5 page testing procedure to find the problem. I'll put the points back in when it stops raining here. Thanks.
Click to expand...
 
(quoted from post at 08:06:44 05/27/22) Owned a 51 8N for 40+ years. Recently, I installed a Pertonix ignition system on my 12V upgrade. It started fine but I noticed an oil leak by the external oil filter. While replacing the fitting to close off the leak, I touched the oil line to the solenoid's back terminal next to the block. This caused a loud spark. After fixing the oil leak, the tractor will not start. No spark at the coil or plugs. Voltage from the ignition key to the terminal block reads 2.5 volts? Any ideas what I did and how to fix it? Thanks.
Click to expand...

GUESSING the engine still cranks normally?

The FIRST thing you need to do is to figure out why there's only 2.5 Volts leaving the ignition switch.

Even WITH a shorted EI there should be full battery voltage leaving the ignition switch.

What is the voltage at the starter solenoid post where the battery connects?

What are the voltage readings on the two posts of the junction block?

Does it have an original "induction Ammeter" or a replacement "two terminal" Ammeter?

If a "two terminal Ammeter" what are the voltages on each terminal?
 
I strongly suspect you burnt out the Pertronix module. I did that once myself. Very annoying.

Pertronix could have included a protection circuit in the module to prevent this, but they didn't.
 
(quoted from post at 15:23:26 05/27/22) I strongly suspect you burnt out the Pertronix module. I did that once myself. Very annoying.

Pertronix could have included a protection circuit in the module to prevent this, but they didn't.
Click to expand...

How does that explain the extremely low voltage coming out of the ignition switch? Somethings got to be getting AWFULLY hot if that's happening.
 
Tested everything again. Battery is 12.6 volts. Starter solenoid post is 12.6. Cranks over no problem. It is a two terminal ammeter with 12.6 volts one one side and 11.25 on the other. The ballast resistor reflects 10.9 on one side and 5.6 on the other. Now the ignition switch reads 12.6 on one side and 11.2 when turned on. I have replaced the battery, starter and solenoid, plugs, coil, rotor, distributor cap, ballast resistor, ignition switch and new electronic ignition system ( after taking out the new points/condenser). It sits outside under a tarp all year when not in use. It sat so long this winter without a start, that I had to prime the oll pump to get oil pressure which is about 40 when running. Missed the old girl last winter plowing my driveway.
 
(quoted from post at 07:28:41 05/28/22) Tested everything again. Battery is 12.6 volts. Starter solenoid post is 12.6. Cranks over no problem. It is a two terminal ammeter with 12.6 volts one one side and 11.25 on the other. The ballast resistor reflects 10.9 on one side and 5.6 on the other. Now the ignition switch reads 12.6 on one side and 11.2 when turned on. I have replaced the battery, starter and solenoid, plugs, coil, rotor, distributor cap, ballast resistor, ignition switch and new electronic ignition system ( after taking out the new points/condenser). It sits outside under a tarp all year when not in use. It sat so long this winter without a start, that I had to prime the oll pump to get oil pressure which is about 40 when running. Missed the old girl last winter plowing my driveway.
Click to expand...

Took a chance and replaced the coil and it started right up. Running like a charm. Pertronix said they didn't think the ignitor was damaged from a spark. It was enough to blow the new coil though. Thanks for all the suggestions and ideas. A memorable Memorial Day for me.
 
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