Grounding lights
- Thread starter Farmer j
- Start date
Charles Coe
Senior Member
Since the lights are grounded through the body you have to have a metal to metal path from the lights. If you have too much paint on all the parts and bolts, you will not have a good ground.
triumphleroy
Member
Running the Ground Wire Is what works the best!
Bob Bidonde
Well-known member
I do the following to assure there is excellent ground continuity:
>Body to Frame: Add a AWG 14 or AWG 16 wire jumper across one of the forward-most cowl to frame body attachment bolts. Clean the bottom side of the frame rail and the top surface of cowl metal bare. Install the jumper and overcoat both sides with paint, clear or body color or black to match. Check the resistance from the frame to the body in several locations. It should be less than one ohm. If more than one ohm,add another jumper at the opposite cowl to frame bolt;
>Dome Light: Add a jumper wire from the body of the light to the body of the car and check the resistance. It should be less than one ohm;
>1930-'31 Dash Light: Clean the faying surfaces of the belt rail and light bracket to bare metal. Check the light body to cowl resistance to assure that it is less than one ohm;
>Instrument Panel: Chase the threads in the cowl tank to assure they are clean to bare metal and install the panel. Check the panel to belt rail resistance to assure that it is less than one ohm;
> Electric Windshield Wiper: Clean the faying surfaces of the mounting feet and the windshield frame to bare metal and install the wiper motor. Check the wiper motor body to windshield resistance to assure that it is less than one ohm. The windshield hinge to the body should have naturally good continuity, but check the wiper motor to cowl body structure to assure there is less than one ohm resistance;
>Engine to Frame: Add a 12-volt battery cable between the frame ground bolt at the battery and the transmission cover. This is especially important if you are running Float-O-Motor engine mounts, but do it for stock engine mounts also;
>Popout Switch Cable: Clean the faying surfaces of the cable at the clamp location, inside and out faying surfaces of the clamp, and the cylinder head and nut to bare metal. Before doing this, lower the coolant level by drain a gallon or so out of the engine. Install the cable and check the ground continuity to assure that it is one ohm or less. Refill the coolant;
>Generator: The continuity between the generator and engine should be naturally good because of the nature of the generator's attachment bolt. Check the ground continuity between the generator and the engine to assure it is less than one ohm;
>Fender Supports to Frame: Clean to bare metal the faying surfaces between both front fender supports and the frame. Install the supports, overcoat the joints with black paint and check the ground continuity to assure that it is less than one ohm;
>Headlight Bar: Clean the faying surfaces of all 4 attachment bolts on the headlight bar and the fender support brackets to bare metal. Install the headlight bar and seal the joints with black paint. Check the ground continuity to assure that it is less than one ohm between the frame and the headlight bar;
>Headlights: The half-round ball on the headlights should be plated. If not, clean the ball surfaces bare. Clean the cups in the headlight bar bare. Install the headlights, and seal the joints with black paint. Check the ground continuity to assure that it is less than one ohm between the frame and the headlight housings;
>Horn: Clean the faying surfaces of the headlight bar and the horn's mounting bracket to bare metal. Also clean to bare metal the faying surfaces of the horn body to the horn bracket. Install the horn and seal all of the faying surface joints with black paint. Check the ground continuity between the horn body and the car frame to assure that it is less than one ohm;
>Cowl Lights: Clean the faying surface between the cowl light mounting bolts and strainers in the cowl structure to bare metal. Install the cowl lights and seal the bolt joints with clear lacquer. Check the ground continuity to assure that it is less than one ohm;
>Distributor: Thoroughly clean the faying surfaces of the distributor and the cylinder head to bare metal. Also chase the threads of the lock bolt in the cylinder head to assure they are clean. Seal the lock bolt with clear lacquer. Check the ground continuity between the engine and distributor body to assure that it is less than one ohm. Inside of the distributor, the upper and lower plates must have excellent ground continuity to the distributor body;
>Steering Column: Thoroughly clean the faying surfaces of the frame-to-steering attachment bolts and seal the joint with black paint. Check the ground continuity between the steering column housing and the frame to assure that it is less than one ohm. Also check the ground continuity of light switch rod to the steering column housing to assure that it is less than one ohm;
>Motometer Light: Run a ground jumper wire from the radiator to the frame.
>Body to Frame: Add a AWG 14 or AWG 16 wire jumper across one of the forward-most cowl to frame body attachment bolts. Clean the bottom side of the frame rail and the top surface of cowl metal bare. Install the jumper and overcoat both sides with paint, clear or body color or black to match. Check the resistance from the frame to the body in several locations. It should be less than one ohm. If more than one ohm,add another jumper at the opposite cowl to frame bolt;
>Dome Light: Add a jumper wire from the body of the light to the body of the car and check the resistance. It should be less than one ohm;
>1930-'31 Dash Light: Clean the faying surfaces of the belt rail and light bracket to bare metal. Check the light body to cowl resistance to assure that it is less than one ohm;
>Instrument Panel: Chase the threads in the cowl tank to assure they are clean to bare metal and install the panel. Check the panel to belt rail resistance to assure that it is less than one ohm;
> Electric Windshield Wiper: Clean the faying surfaces of the mounting feet and the windshield frame to bare metal and install the wiper motor. Check the wiper motor body to windshield resistance to assure that it is less than one ohm. The windshield hinge to the body should have naturally good continuity, but check the wiper motor to cowl body structure to assure there is less than one ohm resistance;
>Engine to Frame: Add a 12-volt battery cable between the frame ground bolt at the battery and the transmission cover. This is especially important if you are running Float-O-Motor engine mounts, but do it for stock engine mounts also;
>Popout Switch Cable: Clean the faying surfaces of the cable at the clamp location, inside and out faying surfaces of the clamp, and the cylinder head and nut to bare metal. Before doing this, lower the coolant level by drain a gallon or so out of the engine. Install the cable and check the ground continuity to assure that it is one ohm or less. Refill the coolant;
>Generator: The continuity between the generator and engine should be naturally good because of the nature of the generator's attachment bolt. Check the ground continuity between the generator and the engine to assure it is less than one ohm;
>Fender Supports to Frame: Clean to bare metal the faying surfaces between both front fender supports and the frame. Install the supports, overcoat the joints with black paint and check the ground continuity to assure that it is less than one ohm;
>Headlight Bar: Clean the faying surfaces of all 4 attachment bolts on the headlight bar and the fender support brackets to bare metal. Install the headlight bar and seal the joints with black paint. Check the ground continuity to assure that it is less than one ohm between the frame and the headlight bar;
>Headlights: The half-round ball on the headlights should be plated. If not, clean the ball surfaces bare. Clean the cups in the headlight bar bare. Install the headlights, and seal the joints with black paint. Check the ground continuity to assure that it is less than one ohm between the frame and the headlight housings;
>Horn: Clean the faying surfaces of the headlight bar and the horn's mounting bracket to bare metal. Also clean to bare metal the faying surfaces of the horn body to the horn bracket. Install the horn and seal all of the faying surface joints with black paint. Check the ground continuity between the horn body and the car frame to assure that it is less than one ohm;
>Cowl Lights: Clean the faying surface between the cowl light mounting bolts and strainers in the cowl structure to bare metal. Install the cowl lights and seal the bolt joints with clear lacquer. Check the ground continuity to assure that it is less than one ohm;
>Distributor: Thoroughly clean the faying surfaces of the distributor and the cylinder head to bare metal. Also chase the threads of the lock bolt in the cylinder head to assure they are clean. Seal the lock bolt with clear lacquer. Check the ground continuity between the engine and distributor body to assure that it is less than one ohm. Inside of the distributor, the upper and lower plates must have excellent ground continuity to the distributor body;
>Steering Column: Thoroughly clean the faying surfaces of the frame-to-steering attachment bolts and seal the joint with black paint. Check the ground continuity between the steering column housing and the frame to assure that it is less than one ohm. Also check the ground continuity of light switch rod to the steering column housing to assure that it is less than one ohm;
>Motometer Light: Run a ground jumper wire from the radiator to the frame.
Last edited:
Richard Lorenz
Senior Member
An important part of the original headlight ground path is between the focusing screw head and the main headlight shell. Clean this location by putting on a drop of penetrating oil and working the screw back and forth. This is easy to do and might cure your particular problem.
Kurt in NJ
Well-known member
The most important thing for good grounds is lockwashers
I think of it as proper restoration---perhaps over restoration, but not just for appearance ---after sandblasting the frame tinning the surface where the battery ground attaches, keeping the paint and primer buildup thin around bolt and screw holes (this helps apperance and grounds, no chipping of the paint), using new lockwashers, the sharp ends dig through the paint, not using hardware with rusty threads ---being aware of the ground path from the starter and generator commutator all the way to the battery ---the generator brush grounds to the end plate, the end plate to the field housing, the field housing to the mounting bracket, the mounting bracket to the engine front cover, the front cover to the block and front mount, bellhousing -on through the suspension to the frame--many of these parts are painted, paint is an insulator (most paint), all held together with bolts,nuts,lockwashers
The electric path of a wire terminal to a stud---from the terminal to theface of the washer, to the other side of thewasher to the face of the nut, then to the threads to the stud ---if any of these areas are rusty,corroded, painted you will have a bad connection
From electrial function standpoint powdercoating is bad, if you dig through the coating to make a ground rust moves quick under the coating
If you pay attention to the whole electric path people will say to you ---your lights are so bright, the engine cranks so fast, you must have 12V
I think of it as proper restoration---perhaps over restoration, but not just for appearance ---after sandblasting the frame tinning the surface where the battery ground attaches, keeping the paint and primer buildup thin around bolt and screw holes (this helps apperance and grounds, no chipping of the paint), using new lockwashers, the sharp ends dig through the paint, not using hardware with rusty threads ---being aware of the ground path from the starter and generator commutator all the way to the battery ---the generator brush grounds to the end plate, the end plate to the field housing, the field housing to the mounting bracket, the mounting bracket to the engine front cover, the front cover to the block and front mount, bellhousing -on through the suspension to the frame--many of these parts are painted, paint is an insulator (most paint), all held together with bolts,nuts,lockwashers
The electric path of a wire terminal to a stud---from the terminal to theface of the washer, to the other side of thewasher to the face of the nut, then to the threads to the stud ---if any of these areas are rusty,corroded, painted you will have a bad connection
From electrial function standpoint powdercoating is bad, if you dig through the coating to make a ground rust moves quick under the coating
If you pay attention to the whole electric path people will say to you ---your lights are so bright, the engine cranks so fast, you must have 12V
