The Ford Barn

ktgarcia · 08-24-2015, 08:29 PM

I have been having trouble posting my text to the forum.

I was able to successfully start my flathead last Saturday and again today. I have to do some carburator adjustments, but it is running.

However, I now have an electrical problem that I am trying to resolve.

When I turn my switch on, the oil pressure gage goes to maximum when the engine is not running. I have checked the gage according to a post on the Barn using a "D" cell and the gage goes to midscale. Is my sending unit bad?

My fuel gage does not register with about a 1/2 a tank of fuel, and I checked the gage the same way as the oil gage("D cell) and it went to midscale. I checked that it had power to the sending unit which is new. I checked the gage with second gage that I had, and it did not register a level.

I also checked the power to the resistor (red wire from the ignition switch) and it was too hot to touch, which seemed to me to be excessive. I would think that I could touch the resistor unit without burning myself.

Is there something I have made a mistake on in wiring up the fuse block, oil and fuel gages?

Thanks in advance for all your help. I could not have got my truck to this stage without all of your input.

K

supereal · 08-24-2015, 10:17 PM

All gauges, except the ammeter, are powered by a common circuit. As you report problems with more than one gauge, check the feed to the gauges for proper voltage, and the various senders for good grounds, as the senders work by providing the grounds. This includes having a clean, tight ground strap between the battery and the engine, as well as the body of the vehicle.

supereal · 08-24-2015, 10:19 PM

I should add the the ignition resistor does get very hot in normal use to protect the coil and points. The gauges should not be fed by the resistor.

ktgarcia · 08-25-2015, 04:01 PM

Sponsored Links (Register now to hide all advertisements)

All gauges, except the ammeter, are powered by a common circuit. As you report problems with more than one gauge, check the feed to the gauges for proper voltage, and the various senders for good grounds, as the senders work by providing the grounds. This includes having a clean, tight ground strap between the battery and the engine, as well as the body of the vehicle.
Before I was able to start my engine, I had grounding problems. I cleaned the surface of the starter and pan, cleaned/sanded the point of contact for the battery cable to the firewall, and the point of contact for the ground strap to the block.

Once that was completed, the start button and the button on the solenoid turned the motor over. Because it had new gas lines, I primed the lines but it still took a little bit to get fuel to the carburetor. Once all done, the engine started. I felt the ground issue would now be solved.

I will check the voltage to the gages, but where should I look for grounding the gages? Do I need to remove the gage cluster and sand the inner surface where the cluster fits. Could it have too much paint present to prevent a good ground?

Thanks again.

08-24-2015, 08:29 PM	#1
ktgarcia Senior Member Join Date: May 2010 Location: Nevada Posts: 115	Starting my flathead I have been having trouble posting my text to the forum. I was able to successfully start my flathead last Saturday and again today. I have to do some carburator adjustments, but it is running. However, I now have an electrical problem that I am trying to resolve. When I turn my switch on, the oil pressure gage goes to maximum when the engine is not running. I have checked the gage according to a post on the Barn using a "D" cell and the gage goes to midscale. Is my sending unit bad? My fuel gage does not register with about a 1/2 a tank of fuel, and I checked the gage the same way as the oil gage("D cell) and it went to midscale. I checked that it had power to the sending unit which is new. I checked the gage with second gage that I had, and it did not register a level. I also checked the power to the resistor (red wire from the ignition switch) and it was too hot to touch, which seemed to me to be excessive. I would think that I could touch the resistor unit without burning myself. Is there something I have made a mistake on in wiring up the fuse block, oil and fuel gages? Thanks in advance for all your help. I could not have got my truck to this stage without all of your input. K

08-24-2015, 10:17 PM	#2
supereal Senior Member Join Date: Jul 2014 Location: Iowa Posts: 1,634	Re: Starting my flathead All gauges, except the ammeter, are powered by a common circuit. As you report problems with more than one gauge, check the feed to the gauges for proper voltage, and the various senders for good grounds, as the senders work by providing the grounds. This includes having a clean, tight ground strap between the battery and the engine, as well as the body of the vehicle.

08-24-2015, 10:19 PM	#3
supereal Senior Member Join Date: Jul 2014 Location: Iowa Posts: 1,634	Re: Starting my flathead I should add the the ignition resistor does get very hot in normal use to protect the coil and points. The gauges should not be fed by the resistor.

08-25-2015, 04:01 PM	#4
ktgarcia Senior Member Join Date: May 2010 Location: Nevada Posts: 115	Re: Starting my flathead Sponsored Links (Register now to hide all advertisements) All gauges, except the ammeter, are powered by a common circuit. As you report problems with more than one gauge, check the feed to the gauges for proper voltage, and the various senders for good grounds, as the senders work by providing the grounds. This includes having a clean, tight ground strap between the battery and the engine, as well as the body of the vehicle. Before I was able to start my engine, I had grounding problems. I cleaned the surface of the starter and pan, cleaned/sanded the point of contact for the battery cable to the firewall, and the point of contact for the ground strap to the block. Once that was completed, the start button and the button on the solenoid turned the motor over. Because it had new gas lines, I primed the lines but it still took a little bit to get fuel to the carburetor. Once all done, the engine started. I felt the ground issue would now be solved. I will check the voltage to the gages, but where should I look for grounding the gages? Do I need to remove the gage cluster and sand the inner surface where the cluster fits. Could it have too much paint present to prevent a good ground? Thanks again.