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Old 03-26-2008, 04:32 AM   #1
68gmsee
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In case there's any doubters re: grounding.

I want to thank all of you who have been telling us, for quite some time, that we need to make sure we have good grounding on these old trucks. I thought mine was ok but found out I was wrong.

I did a search to find out what the rest of you all are doing and decided to do the same. Seems that on these old trucks the rust, dirt and grime builds up on the bolts to the cab, frame and bed and we loose good contact.

Here's my experience.

A couple of weeks ago I decided to reposition the bed. It was slightly off center. That's when my rear lights decided to do some weird stuff.

I had no rear lights and no brake lights with the light switch on. If I turned light switch off, my brakes lights worked. Also license plate light decided not to work either. My rear blinkers stopped working.

All this time I thought I had a good grounding on the truck. I did a search to find out what the rest of you all are doing and decided to do the same.

Action plan: Went to the local auto parts and bought 3 braided cables and one 19 inch black ground cable. Box of assorted star washers.

Ground cable from block to the frame.
Ground cable to the radiator support.
Ground cable from cab to frame.
Ground cable from bed to frame.
Made sure I had good clean connections and put star washers on all the ends.

All my lights are working and even look brighter. And the bonus, my alternator guage started to work. I had thought I had a bad guage...

Last edited by 68gmsee; 03-26-2008 at 04:36 AM.
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Old 03-26-2008, 04:35 AM   #2
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Re: In case there's any doubters re: grounding.

Cool! I'm probably gonna try that. I'm having a couple of goofy problems in my '67 as well with the instrument panel. Thanks for the heads up.
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Old 03-26-2008, 04:42 AM   #3
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Re: In case there's any doubters re: grounding.

I've seen bad grounds cause the wierdest problems, dash lights blinking with turn signials, radio coming on with brakes, ect. I've learned that when something wierd happens electrialy always check the grounds first.
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Old 03-26-2008, 04:43 AM   #4
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Re: In case there's any doubters re: grounding.

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I've seen bad grounds cause the wierdest problems, dash lights blinking with turn signials, radio coming on with brakes, ect. I've learned that when something wierd happens electrialy always check the grounds first.
Man, I hear ya.. I thought I had gremlins in there after I all the weird problems.
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Old 03-26-2008, 04:45 AM   #5
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Re: In case there's any doubters re: grounding.

Great post I'm going to re-wire my 67 this weekend with a new kit from ez wiring none of my gauges currently work so I'm guessing that the grounds are bad now. Or it could be the 10k splices in the harness what a mess. Found a bunch of wires that were exposed with no insulation. lol no heat either. I'm a mazed it never smoked.
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Old 03-26-2008, 04:46 AM   #6
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Re: In case there's any doubters re: grounding.

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Cool! I'm probably gonna try that. I'm having a couple of goofy problems in my '67 as well with the instrument panel. Thanks for the heads up.
Even if it's not the problem now, it may prevent some in the future (as in my case). It certainly was weird. Worked one week and then go to check and they're all screwed up..
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Old 03-26-2008, 04:48 AM   #7
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Re: In case there's any doubters re: grounding.

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Ground cable from block to the frame.
Ground cable to the radiator support.
Ground cable from cab to frame.
Ground cable from bed to frame.
Made sure I had good clean connections and put star washers on all the ends.
.
"ground cable to the radiator support" ? Where does this one tie into?
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Old 03-26-2008, 04:59 AM   #8
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Re: In case there's any doubters re: grounding.

Yep, most weird electrical problems are from poor grounds. Always the first thing to check. Many OE's have gone to the extreme on new trucks- they put battery cable size ground cables from one frame rail to the other- not trusting bolts/ rivets in the crossmembers. Most have gotten away from star washers also- and for good reason. I hate them. In the rust belt, road salt gets into them & you loose connection. A flat shouldered nut with dielectric grease or sealer is best. Same goes for the starter connections.
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Old 03-26-2008, 05:01 AM   #9
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Re: In case there's any doubters re: grounding.

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"ground cable to the radiator support" ? Where does this one tie into?
I went from a point near the front of the frame into one of the bolts that holds the lower radiator "cradles" in place... It doesn't really matter where you ground as long as there is good metal to metal contact on the ground strap.

I will confirm what others have said... My headlights, brake lights, etc are super bright. Nobody can convince me that the lights in these old trucks are just supposed to be dim because they're old... Mine are as bright as any I've seen - old or new.
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Old 03-26-2008, 05:09 AM   #10
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Re: In case there's any doubters re: grounding.

take it one step furhter,,, locate the 2 grounding points on the rad core support, remove them, clean them, reinstal, and realize your headlights are brighter. A former member told me when i did hers a few years ago "It's like it's someone else's truck" (first ohio board meet... 03 I think)
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Old 03-26-2008, 05:28 AM   #11
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Re: In case there's any doubters re: grounding.

it never ceases to amaze me the dollars people will throw at a problem while being told repeatedly BAD GROUND and refuse to take a few bolts out and use a piece of sandpaper to establish a good ground to complete a circuit
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Old 03-26-2008, 05:32 AM   #12
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Re: In case there's any doubters re: grounding.

Could my starter be malfunctioning b/c of a bad ground?
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Old 03-26-2008, 05:49 AM   #13
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Re: In case there's any doubters re: grounding.

Quote:
Originally Posted by imholte View Post
"ground cable to the radiator support" ? Where does this one tie into?
Actually, I put a braided cable directly from the battery ground post to the radiator support. There was a threaded hole on top and just used it.
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Old 03-26-2008, 05:52 AM   #14
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Re: In case there's any doubters re: grounding.

ed the starter is bolted directly to the engine, which is where the neg cable should be ... odds are, no. Whie it IS possible in theory, I have never heard of nor seen this ever happening.
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Old 03-26-2008, 05:53 AM   #15
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Re: In case there's any doubters re: grounding.

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Could my starter be malfunctioning b/c of a bad ground?
a perfect example the time it took to type and hope for a responce you could have taken a piece of sandpaper and gotten your answer
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Old 03-26-2008, 05:57 AM   #16
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Re: In case there's any doubters re: grounding.

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it never ceases to amaze me the dollars people will throw at a problem while being told repeatedly BAD GROUND and refuse to take a few bolts out and use a piece of sandpaper to establish a good ground to complete a circuit
Yep... The problem occurs when the trucks work fine all these years and all of a sudden weird things start to happen. We start chasing the gremlins around.

But, since I've been reading the posts about grounding and the recommendations by everyone, it helped me make a quick determination.

Longhorn Man's comment about "overkill" on his truck was right on. Can't have enough grounding...
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Old 03-26-2008, 05:57 AM   #17
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Re: In case there's any doubters re: grounding.

Ok, i guess i deserve that, the thing is just po'ing me. I do need to check my grounds. That is for tomorrow morning since there is no school.
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Old 03-26-2008, 06:28 AM   #18
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Re: In case there's any doubters re: grounding.

nobody mentioned the two ground wires from the firewall to the valve covers//i always went to bigger gauge wire on them and put them to the accessory holes in the back of the heads so to clean up the looks of the engine
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Old 03-26-2008, 06:31 AM   #19
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Re: In case there's any doubters re: grounding.

How about every time you get in your truck you ground yourself to the frame to eliminate all issues?
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Old 03-26-2008, 06:55 AM   #20
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Re: In case there's any doubters re: grounding.

Quote:
Originally Posted by cdowns View Post
nobody mentioned the two ground wires from the firewall to the valve covers//i always went to bigger gauge wire on them and put them to the accessory holes in the back of the heads so to clean up the looks of the engine
if the frame and cad are grounded, and the engien and frame, there's absolutly no reason to add the clutter of the valve cover straps.
Personally, i've always thought those were retarded myself.
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Old 03-26-2008, 07:00 AM   #21
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Re: In case there's any doubters re: grounding.

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if the frame and cad are grounded, and the engien and frame, there's absolutly no reason to add the clutter of the valve cover straps.
Personally, i've always thought those were retarded myself.
How about we also ground the camshaft, just to be sure,
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Old 03-26-2008, 07:10 AM   #22
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Re: In case there's any doubters re: grounding.

Go ahead and try that one... get back with me on your results.
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Old 03-26-2008, 07:12 AM   #23
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Re: In case there's any doubters re: grounding.

We could go even further... electrolosis. Take a DVOM neg. lead to the battery neg. post, and stick the pos. lead into the coolant in your radiator. You might be surprised what you see. Corrosion isn't the only thing that damages radiators, heater cores, and in extreme cases... blocks.
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Old 03-26-2008, 07:15 AM   #24
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Re: In case there's any doubters re: grounding.

Thx andy, the only time i will ever ground a cam is if i set the old one on the floor, lol
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Old 03-26-2008, 08:08 AM   #25
Longhorn Man
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Re: In case there's any doubters re: grounding.

Quote:
Originally Posted by jeffspower View Post
We could go even further... electrolosis. Take a DVOM neg. lead to the battery neg. post, and stick the pos. lead into the coolant in your radiator. You might be surprised what you see. Corrosion isn't the only thing that damages radiators, heater cores, and in extreme cases... blocks.

What are you making reference to? You should have 2.1 volts per cell... is that what the surprise is?
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