Help!!! 1974 351c engine ground wire locations |
Post Reply |
Author | |
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
Posted: 27-March-2019 at 4:17AM |
Hey guys first time on a forum here. Ive got a 1974 gran torino with a 351c 2v. Recently i spent the day at Summit Point race track in west virginia. I took the car to the car wash and when i was wrapped up the car wouldnt start. I heard some clicking got a jumpstart and was on my way. I then drive about 15 miles to the track without issue. A few hours later same symptom clicking as if ive got a dead battery. Long story short i got 4 jump starts to cover maybe a mile. The cars been on the side of the road now for 4 days. First thought alternator. Bought one tested the old one. Old one was good and just to be safe i had the new one tested also; good as well. I try both alternators in the car and watch my voltmeter drop like a rock everytime. I then replace the voltage regulator and for sure same readings with voltage steadily dropping. Ive been told a few times to check my grounds but dont know where they all are. A schematic or a picture would be helpful. May be unrelated but had my passenger valve cover gasket fail recently and this soaked the block with oil. I brake cleaned most of it and the car ran fine without leaks for a week before this happened. Behind the alternator on the front of the block are there any grounds? And could that oil seepage be a culprit to my troubles? Ive checked my connector for the regulator and it seemed fine the wirings intact and not dryrotted between there and the alternator, needless to say im stumped.
Edited by 74GranTorino4dr - 27-March-2019 at 4:26AM |
|
72FordGTS
Admin Group GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 5802 |
Post Options
Thanks(0)
|
Welcome to the forum! The battery negative cable should run to the engine block, under at the front of the engine under the right cylinder head (near alternator). There is a ground wire from the engine to the firewall on the back of the right cylinder head.
You can try and replace the engine ground. Getting a new cable from a parts store is cheap and they are easy to replace.
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
what ^^^ Vince said the only engine grounds are the battery cable from the Neg battery terminal to the engine block, not the water pump or front brackets or even the cylinder head, to the block! and a ground from the back of the cylinder head to the firewall to ground the body. what makes you think the battery isn't toast? FWIW replace the battery Neg cable before you do anything else, it's cheap and may well be the whole problem, and the battery.
Edited by Rockatansky - 28-March-2019 at 6:23AM |
|
72 GT Ute
|
|
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
|
So were talking checking the grounds. Yesterday i returned to the car and checked the ground for the regulator where it connects to the radiator support. I was sure it wouldnt do anything trying to clean it but hey at this rate i did anyway. In my scowering of the engine bay i noticed my negative battery cable is new. Much newer then some of the other stuff. I triple checked the wiring for the alternator and got a second opinion still have a 3-wire alternator and it is wired properly. I found that my starter cable had been chewed up by something so bare wire was exposed. Being on the side of the road i reinsulated that cable with tape and put it back in there. At this point we connected the jumpers and on each attempt to start the car sparks arched from the solenoid onto the fender. This is a new symptom. I have not checked for a ground near the firewall but the metal on this car is phenomenal. So i imagine there could be a break in the wire somewhere back there i may just have to drive out again. With the volt meter we got a more or less steady 11.8-12.1 volts running. The moment i hit the lights or open a door that volt meter drops like a rock to 6v before it dies. Seems likely its the ground for the body? The one by the firewall even? Ive done my best keeping all accessories off just for the sake of trying to get some charge to happen. Maybe i answered my own question. But would that explain the arching from the solenoid? Fuses in the dash still seem fine wheather or not they could be culprits. Thoughts?
|
|
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
|
i believe the battery is fine each new day out at the car were getting 11.98 before we make any attempts to jumpstart. Althpught with that reading the car will not start on its own; being so close to 12 i think it should. Not withstanding i had the battery replaced a month ago it couldve gotten some cell damage from the lack of recharging but i feel this is unlikely due to the consistant readings.
|
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
where is the ground connected to the engine? and did you clean the connection yet? |
|
72 GT Ute
|
|
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
|
Its located behind the alternator near where a bracket holds the starter cable to the block. Within a few inches. Used a wire brush and scored the surface contact and the bolt itself before putting it together. I have yet to check the ground near the firewall but on a another thread here a guy had a similar issue and that ground in question should start near the trans dipstick and go to the firewall i believe. Thats where im aiming my sights next.
|
|
whmitchell
New Member Joined: 04-June-2018 Location: ON Status: Offline Points: 19 |
Post Options
Thanks(0)
|
Your battery should be around 12.6 volts or above if it's still good.
|
|
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
|
I feel like regardless 11.98 or 12.6 that with the alternator functioning properly it shoukd still run on its own. Heading to the car now volt meter in hand well see what we get looking at that other ground. And were planning on taking that battery with us when we leave. Provided the priblem persists.
|
|
72FordGTS
Admin Group GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 5802 |
Post Options
Thanks(0)
|
Even if the ground cable looks good, it could be bad. I agree with Rock, it's cheap to replace, so might be worth trying. Also remove the cable and clean the contact on the block. Do you have another battery from a running car you can try out too?
Did you go over your wiring between the alternator and the voltage regulator to make sure it was all correct and there is not broken/shorted wires? Might be worth checking the wiring's continuity with the voltmeter.
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
74GranTorino4dr
New Member Joined: 27-March-2019 Location: Winchester Va Status: Offline Points: 25 |
Post Options
Thanks(0)
|
Alrighty guys so i have checked the wiring between the regulator and alternator. Wires all look good no signs of anything unusual. Although upon a closer inspection i noticed the ground to the firewall is absolutely toast. There isnt one bit of insulation left and that copper is easily three different colors. I bet that its not grounding at all but boy is the bolt on the block a tough one to get to. Not enough room for regular sockets and my offset wrenches fit but are only worth about a 32nd of a turn. So i believe this could be my culprit. The battery on the other hand couldve suffered as a result of the ground burning up. Can i substitute that ground elsewhere? Maybe from the battery ground location to the frame or does it need to be where its at?
|
|
dave302
Senior Member Joined: 08-October-2009 Location: usa Status: Offline Points: 3171 |
Post Options
Thanks(0)
|
If you can drill a small hole in the drivers side firewall, then you can connect it to the rear of the left side cylinder head. You might have to remove some paint from the cylinder head and firewall to get a good connection. Many of the accessories, lights and the instrument panel are all grounded to the dash, firewall and the body of the car. That strap is the electricity's path back to the battery. You have to have one from the body/firewall to the engine. Edited by dave302 - 29-March-2019 at 11:19AM |
|
dave302
Senior Member Joined: 08-October-2009 Location: usa Status: Offline Points: 3171 |
Post Options
Thanks(0)
|
Starting in 1974 the rear license plate light was grounded to the frame through the rear bumper. In '72 and '73 it was grounded to the body. A ground strap from the frame to the body, and the engine to the frame would probably not be a bad idea. But the strap from the firewall to the cylinder head is probably more important at the present time.
Edited by dave302 - 28-March-2019 at 11:53AM |
|
dave302
Senior Member Joined: 08-October-2009 Location: usa Status: Offline Points: 3171 |
Post Options
Thanks(0)
|
I have also seen a ground strap from the front upper control arms to the frame on both the drivers and passenger side. It was on a '74 ranchero and it appeared to be original from the factory.
I am not sure why it was there, but I had heard of a story where a car had a broken ground strap and one of the front wheel bearings had burned. Since electricity will always take the shortest path to ground. |
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
AFAIK the body ground from the back of the head to the firewall has always been an uninsulated braid. you should be able to find a replacement at most parts stores. use a slightly larger size sheet metal screw to gain a fresh cut in the metal and establish contact. Yes a good battery should test above 12v, charging volts above 14v. the battery should last longer than "4 jump starts to cover maybe a mile" unless you had the high beams on and a megawatt amp running? get that thing off the road and test the charging system!
|
|
72 GT Ute
|
|
dave302
Senior Member Joined: 08-October-2009 Location: usa Status: Offline Points: 3171 |
Post Options
Thanks(0)
|
There is a picture below of where the front brake lines are connected to the frame. This was near the location that I saw the straps connected from the front upper control arms to the frame.
|
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
yes the control arms can have braided ground straps, not sure why exactly, could be something to do with RF from the bearings? the P71 Crown Vics have ground straps on everything to reduce RFI, even the exhaust system
|
|
72 GT Ute
|
|
1973gts
Senior Member Joined: 05-March-2018 Location: Grand Rapids Mi Status: Offline Points: 608 |
Post Options
Thanks(0)
|
Here is a picture of one of my grounds that runs from the upper control arm to the frame and there is another one on the other side just like this. It is a little hard to see but it has a clip on one end that attaches to the opening in the top of the control arm and the other end attaches to the frame in front of the control arm. As mentioned it is a braided cable.
|
|
Dave - 1973 GTS N code
|
|
californiajohnny
Moderator Group Joined: 05-October-2013 Location: winlock, wa Status: Offline Points: 14606 |
Post Options
Thanks(0)
|
that clip on mine was attached to the inner fender well.
the battery is grounded to the block, make sure you have or add a good heavy ground from the block to the frame somewhere(you can make one down low out of sight) and a ground from either the block to the body like original at the back to the firewall or do what i did added another heavy gauge one under the car from the frame to the body |
|
JOHN
74 GRAN TORINO S&H CLONE 74 VETTE CUSTOM 90 S10 BLAZER 4X4 LIFTED 77 CELICA CUSTOM 75 V8 MONZA SUPERCHARGED 79 COURIER VERT. SLAMMED 75 VEGA V6 5 SPD 70 CHEV C10 P/U 68 MUSTANG FB CONVERSION |
|
californiajohnny
Moderator Group Joined: 05-October-2013 Location: winlock, wa Status: Offline Points: 14606 |
Post Options
Thanks(0)
|
the sparks you mentioned from the solenoid.... are they arcing where it's mounted to the fenderwell?(2 little mounting screws) that needs to be clean tight and grounded for the solenoid to work!
|
|
JOHN
74 GRAN TORINO S&H CLONE 74 VETTE CUSTOM 90 S10 BLAZER 4X4 LIFTED 77 CELICA CUSTOM 75 V8 MONZA SUPERCHARGED 79 COURIER VERT. SLAMMED 75 VEGA V6 5 SPD 70 CHEV C10 P/U 68 MUSTANG FB CONVERSION |
|
MrSmog
Senior Member Joined: 21-January-2016 Location: Ky Status: Offline Points: 1407 |
Post Options
Thanks(0)
|
yep check that solenoids mountin, clean real good and smear some dielectric grease on it. I ran my 86 omni glh turbo at summit point years and years ago, never heard anyone outside of the md/va/w va area even mention it before. Brings back some good memories, especially at the golden horseshoe in ranson wv, or if you are lower on funds the huddle club. They'd have over 20 dancers there and one full set of teeth between em all lol
|
|
Post Reply | |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |