To ground the hood, the factory used a spring like piece of copper sheet that is bolted on top of the upper cowl and scaps against the underside of the hood. If the hood is closed, it is grounded via this spring.
The spring I have is well worn and ugly. Further, I do not like the idea of something scraping the paint from my hood, even if it is on the underside.
Did you re-install that spring after your restoration? If not, is there any negative effect to be expected if it is missing (I assume it is there to suppress possible radio interference)?
If it is advisable to have the hood grounded I think I would prefer some kind of ground strap.
Thank you, Manfred
This is a good question.Waiting to see what the answer well be.
01-04-2011, 12:36 PM
(This post was last modified: 01-04-2011, 12:36 PM by droptop73.)
Just thinking out loud here. Why does the hood need to be grounded to the cowl when closed? The light (if you have one) operates when the hood is open. That is the only circuit I can think of under the hood. Maybe it's an anti static thing. ???
Low buck, touring style, '73 Convertible "rolling restoration", 351c, 2v heads with a shave and a haircut, Performer intake, Holley 650(ish), roller rockers, screw in studs, guideplates, stainless valves, Duraspark / Motorsports MSD, T-5 conversion. 1-1/8" front, 3/4" rear swaybars KYB shocks and some home brewed subframe connectors. Future plans; JGC steering box, Cobra brakes and... paint, interior, etc.
When I die I want to die like grandpa, peacefully in my sleep... not screaming, like his passenger.
well my car didn't have one originally during engine bay restoration in 2007 a friend gave me one, its really just for show it doesn't do anything you can bend your bracket down a little and it won't rub the paint but look like its doing the job by just existing.
it was suppose to help prevent the hood movement from causing extra electrical radio noise that would come out the the cars radio speakers, but it doesn't do anything really. the hood is grounded through the hood hinges anyway.
it has no benefit that i could tell when i tried it other then ruining paint under the hood.
I think the argument was the cars hood is REALLY big and driving it down the road would build up a static charge on the surface, but the hood isn't isolated the front is because it sits the little rubber bumpers and the fenders have the 4 rubber isolators but the back half where the hinge is, is not isolated. the hood is tied into the body with no isolation through the engine bay aprons so i don't understand why they felt the need to install a tiny copper plate that rubs the hood hit or miss depending on age in some vain attempt at discharging the hood through the cowl area, when its grounded on both sides through the hinges into the natural Negative ground of the body. I know they left the hinges untreated raw metal and over time they would rust over but if you opened and closed the hood every so often the rust would break loose and re-establish any lost conductivity.
I mean if ford was so crazy back then to isolate the electrical system then why not run a wire for ground and not use the body itself and then tie in each piece to the ground directly. lol
oh and the hood light if you had one was driven by a mercury switch so that little tab does not provide any 12 volt or direct negative tie in for a light. the car body is basically energized all the time since its used as a direct ground back to the battery. the hood light has a 12 volt positive wire that feeds it, but the hood is ground, when the hood is opened the mercury bubble makes contact and the light turns on, 12 volts positive is always flowing through the feed wire regardless if the hood is open or closed, its only when the hood is in the open position that the mercury switch kicks on completing the light circuit at that point the little ground tab on the cowl isn't touching the hood at all.