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Electrical Expert? (engine ground)


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I was given this scrap house wiring, 7 strand aluminum something or other. It is one of the 3 mains going to a house, new never used. I spotted my old copper engine ground and thought of this scrap wiring, which seems to be similar guage as the main engine ground by driver side cyl head. Can I use it safley, accurately like oem? I just installed a new alt, and don't even want to try it without an expert opinion.

enginegroundmz8.jpg

 

it is no doubt outdoor wiring, as that is where I spotted the new cable going to the house , the same as this scrap.

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If it is the same gauge as the other wire, definitely only use it tandem with the OEM one. Aluminum has a higher resistance than copper. And don't mount copper and aluminum together or they will react.

 

thanks. if wired together, resistance could increase, so parallel, say on the other side of engine, won't hurt anything? it will decrease what resistance exists and that is a major part of this question. I do have an ohm meter, I should compare same length of aluminum with oem engine copper. If to change length to get same numbers, there is plenty of direction to mount it slightly differently. :)

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Aluminum wire is not used any more for a reason. It will start to oxidize and crystallize over. Aluminum wire becomes very brittle in short times.

 

They don't use it in houses anymore for a reason.

 

BTW: Aluminum and Copper have close to the same resistance. That's how you get away with grounding everything to your engine block.

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Aluminium wire is used very extensively - especially in transmisison - , due to its low cost compared with copper.

 

While it doesn't conduct quite as well as copper, the difference is negligibile for your application.

 

To answer your question, yes, if you wire it in paralell with the other one, it will decrease the resistance. Certainly cant hurt - if it breaks you're just back to where you started from.

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It is worth a try.The carb versions seem to be gentle runners- a good sensitive wiring replacing the 20 year old copper stiff one was an idea I will pursue. My loyale engine ground is slightly different and more flexible.I can't seem to find it however...:rolleyes: as I had junked my loyale and saved everything I could.

The wire in question is brand new from a brand new house, from pole to house, meant to take natures beating, and aluminum based is on all the poles that carry electricity. I am not sure where the idea of aluminum based wiring is not used anymore for large scale operations for 50 years at a time for all we know ( a tree would have to knock it down for it to be replaced here- and most of it really is going on 50 years). To put a new version on something pretty much for the quick high volt stab of a spark plug should work. If not, 18 inches or so of same oem wire would work, I am looking at the cheapest way out first.

I remember this experiment in high school days, as the battery got caught on the engine ground and the battery broke it- unknown to the owner. car ran strangely- it seemed to take forever to recover even after replacing. I probably don't even need one, I am noting an amp draw possibly due to new metal and paint etc, even on some internal unibody channels, and weather is really diving into the cold fast. Tonight it is first night for single digits (F). Patience to wait is a good thing to have on this subject no doubt. The spfi soobs seems to keep the car "lit" in the same areas of electrical, unlike natures carb.

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Aluminum work hardens, so the vibration from the engine will crack and break it fairly quickly (compared to the life of the copper wire). Not to mention that the insulation isn't rated for the temperatures it will see underhood.

Also, large strands are good for high voltage, but it will have measurably more resistance than the fine stranded copper wire that's there. You would be best off replacing the existing engine to body ground with an 8ga fine strand copper cable, 10ga could be used since it's essentially a backup. Replace the main engine to battery ground with a length of 2ga welding cable (fine strand) and the car will crank over like never before.

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Aluminum work hardens, so the vibration from the engine will crack and break it fairly quickly (compared to the life of the copper wire). Not to mention that the insulation isn't rated for the temperatures it will see underhood.

Also, large strands are good for high voltage, but it will have measurably more resistance than the fine stranded copper wire that's there. You would be best off replacing the existing engine to body ground with an 8ga fine strand copper cable, 10ga could be used since it's essentially a backup. Replace the main engine to battery ground with a length of 2ga welding cable (fine strand) and the car will crank over like never before.

 

Very good advice. I have declared it expert enough to take listen. How did you know the starter was a bit slow...?

I did find my loyale starter and cables, will go with that as the loyale was very good there. I have not overruled my thoughts on this car getting struck by lightning. Strange body injuries, and that engine ground does not seem like oem at all.It seems the stiffness of ground on this carb soob has me associating it with something you could find on a lightning rod. I do not believe it is original, as even the length seems odd for its route. Thanks for advice, will try it out for the engine ground.. 8 guage to 10 guage insulated and loyale starter cables.:)

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When aluminum corrodes, it creates aluminum oxide (Al2O3). Aluminum oxide is a very good electrical insulator. Do you want an electrical insulator in your engine ground circuit? I would think not.

And before you say it probably wouldn't corrode to that point, I've already had one do that on my '83 wagon (factory wiring) - causing a no-start that seemed like a dead battery. Removed terminal, sanded corrosion off wire, presto-starto.

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I have since changed my mind again...

 

I had to think back to my other 87 and its symptoms (much further beaten) and the electrical strain in the cold lead to a bad fuel pump- it simply died over 2 seasons later. This car is there, at that straining point, same symptoms, like rear defrost pretending to use 1million amps (slightly exxagerated).The strain is as random as the pump warm or cold. The cold idle takes a loooong time to get up to the 1500 rpm I have it set at. My old 87 did the same thing, and was cured entirely, electrically after the fuel pump swap, as well as snappy cold starts into the -20's F. The old one after this fuel pump allowed me to keep running the very same battery 4 years later in its 3rd soob @ a tiny 325cca (good sign electrical was flawless- after the fuel pump swap). I had thought of it already, but shrugged it off. Also, on this car, the pump is literally silent getting right next to it. My other soobs were audible, and in the frigid, audiblae inside the car. this one has no signs of powerful life. All other electrical checks are good- it is identical to my other 87's symptoms, just had to remember.

"If the ground isn't broken, you aren't fixing anything" is advice I am taking.

 

On spfi swap if I ever give up my likeness for the hitachi, the engine ground will be a loyales, along with starter wires etc.

 

Thanks for tips about aluminum wires, will not use them ever..:)

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There typically is not a problem with decreasing the resistance of your grounds as long as you add on.

 

http://forums.nasioc.com/forums/showthread.php?t=1118392

 

Good info on Subaru's in general. The biggest difference has been said to be the battery-->chassis connection. Some 8 gauge or 4 gauge wire run there will help all that current to flow from your battery. The other ones will help the alternator current flow in and out of the battery and also into the chassis.

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The carb pumps seem to make less noise than the SPFI ones. Less pressure, so mabe less noise?

 

Aluminum wiring was hot back in the 70's I think. Lead to a bunch of trailer home fires. The aluminum would expand more than the steel screws used at switches and outlets, and would work it's self loose. Resistance at the connection would go up, more heat would be created, and eventually it would catch fire.

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