You will get a charge out of this!

[Forest Road 594]

Insomniac rule #1..... If you must be up find a topic which holds your interest. Thanks for the post Chuck!

Whoever made the repairs to that 6" copper science experiment has probably burned down a few houses as well. Wiring is no hobby! Thank you for exhibit Number 1!

[WheelHorse_of_course 100]

So how about temporarily putting this on a good tractor and measuring the voltage drop.

Then a lesson on ohms law and calculate how many watts are being eaten by this cable alone?

Cheers

:thumbs:

[horsefeathers 15]

Old_Iron, I don't think this is a good time to "Stir up the troops" So I'll make a statement!

I 'am an under educated, blue collar, high school drop out! (Three strikes)!

Took, Automotive trades in high school Vo-Tech,I learned a lot that I forgot!

No other continued education! I learned on my own by doing! (Amazing what you can learn)!

When something broke I walked to the public library read books, wakled home and fixed it!

Worked in the 80's as an Electronics Assembler, Certified Solderer Mil-Std-45743,DOD 2000 Military Contracts.

We maid necular warhead cables! Don't know how it works! But I can assemble it!

Now I go to school on line! SOI Universary Rules!!

Rolf has a great idea! Now... let's learn somthing!!!

HORSEFEATHERS!

SAVE THE "CATMAN"!

[Save Old Iron 1,572]

So how about temporarily putting this on a good tractor and measuring the voltage drop.

Then a lesson on ohms law and calculate how many watts are being eaten by this cable alone?

Cheers

:thumbs:

[HorseFixer 2,013]

With wireing like that I dont know why I wasted My Money on #2 Ga. Cables!

[horsefeathers 15]

Very nice Duke! That's a lot of copper! May want to put some diaelecrtic grease on to advoid corrosion.

It always scares me to see a fuel line around all that electrical stuff!

Seriously everyone keep a charged fire extingusher close at hand!

Yes ....I have Issues with fire!

HORSEFEATHERS!

[squonk 44,747]

With wireing like that I dont know why I wasted My Money on #2 Ga. Cables!

Did the same thing on my 83 Goldwing. They have lots of starter issues. Got a 350CCA gel bike battery, added some gonzo cables and now it about flips the bike

over when you hit the button. I've seen lots of guys brag about the "giant" battery they have in their tractors, but then they got shot/puny wires going to them. A lot of good all of those cranking amps will do when their sittin n the battery and cant get out because the cables are shot or the connections are bad.

[rmaynard 16,646]

Duke,

Just a quick question. What is your rationale for connecting the ground wire to the tank support

and not directly to the engine/frame bolt?

Bob

[Save Old Iron 1,572]

Duke,

Just a quick question. What is your rationale for connecting the ground wire to the tank support

One possible answer

so when the orange wire with the full 12 volt supply chaffs thru the rough edge on the chassis support and shorts to ground,

the electrons won't have as far to walk home as the operator of this tractor

easy fix here - just reposition the wire or address the rough and unfinished edges of the chassis.

[dkopp 1]

Very nice Duke! That's a lot of copper! May want to put some diaelecrtic grease on to advoid corrosion.

It always scares me to see a fuel line around all that electrical stuff!

Seriously everyone keep a charged fire extingusher close at hand!

Yes ....I have Issues with fire!

HORSEFEATHERS!

Don't fly then...you know they route wires in fuel tanks for the fuel pumps and these wires are not in a sealed conduit.

[sorekiwi 761]

With wireing like that I dont know why I wasted My Money on #2 Ga. Cables!

Another dumb question from me Chuck!

When we throw away the battery leads like the one in your example, what size wire should we be selecting for the replacement?

Depending on what table you look at it would seem that Dukes 2 gauge wiring is good for over 200 amps. The same table states that 8 gauge wire would be OK up to 100 amps. It seems that the auto parts stores are selling battery cables around about 6 gauge.

So what do we need for our tractors? Since the leads are usually only around a foot in length, and we are now providing squeaky clean terminals and ground connections, probably 6 gauge would still be overkill?

And another thought, the ignition switch on a S/G equipped tractor is only rated for 70 amps, so maybe we only need 8 gauge here?

I have just realized that I have been thinking about the biggest load on the cables being the starter, but in Dukes case he needs those big wires to run his lights etc!

[linen beige 15]

And whats up with all those dent marks in the top of the terminal connector ?

Looks like someone used the boxed end wrench they had in their hand as a hammer to "seat" the clamp over the battery post.

And nobody noticed the steel washer against the copper wire? Galvanic corrosion in progress.

[Save Old Iron 1,572]

Mike,

an excellent question that snuggles up rather closely to the theory a racing stripe makes your car go faster and I can get more horsepower from my 12Hp Kohler if I increase the fuel line diameter from 1/4 to 3/8 inch!!

All sounds great until you have to "prove it".

By calculation, 2 awg has a resistance of about 0.0001563 ohms / ft

6 awg has a resistance of about 0.0003951 ohms / ft

So a little Ohms law here to calculate the voltage drop across the starter wire at a 50 amp draw.

E = I x R

E = 50amps x 0.0001563ohms (2 awg) = 0.007815

which means your fully charged (if it is fully charged) battery at 12.6 volts will now deliver only

12.592185 volts

to the starter (if the rest of the starter has has resistance - which it does)

So now lets be an "average, no user serviceable parts inside type of guy" and use 6awg wire.

E = 50amps x 0.0003951 ohms (6awg ohms per foot) = 0.019755 volts dropped

leaving a mere 12.580 volts available from the battery.

12.59 vs 12.58 volts - open your wallet and choose what makes you feel better.

But wait , why does the cranking voltage drop almost to 10 volts across the battery terminals when you crank the engine ?? Isn't that a whole heck of a lot more important than the gain of a fraction of volt from bigger battery cables?

You betcha !! But why are we dropping so much voltage even with shiny new big honking battery cables hooked to a 12 Hp engine?

Because the internal resistance of even the best lead acid battery is about 0.01 ohms WHEN FULLY CHARGED. So right off the bat, the internal resistance of the battery is almost 100 times greater than the 2awg cable and 25 to 30 times greater than the 6 awg cable. Those numbers are the result of the physical properties of the material used to create the battery and the characteristics of the chemical reaction taking place within the battery. You and I are not going to change those properties.

Weakest link in the battery current chain is ..... ding ding, you got it right on the first guess ...... the battery itself.

If its my wallet, I'm saving up to increase the aerodynamics of my tractor by putting hubcaps on the wheels. With the decrease of wind resistance and turbulence , I'll expect to get at least 3 or 4 more feet of travel out of a full tank of gas! Maybe 5 feet if I increase my fuel line diameter to 3/8 of an inch instead of 1/4 inch.

But of course this is only a scientific analysis, people do what people do for all kinds of reasons. An explanation of those reasons will cost you extra.

[Save Old Iron 1,572]

I have just realized that I have been thinking about the biggest load on the cables being the starter

another thing to consider

ever open up a starter ?

do you see 2 or 6 awg wiring inside the case ?

so why FEED IT with 2 awg on a starter that can't draw more than 50 + amps.

:ychain:

[squonk 44,747]

Even cables that look half way decent can be bad. Here are some pics of the cable from the starter to the solenoid on the C-160 I just got today. The solenoid just clicked. I kept trying it until I saw tiny sparks around the terminal at the solenoid. The wire was loose in the crimp and there was some corrosion in there. Going to get a new cable made up on Monday.

[Save Old Iron 1,572]

I saw tiny sparks around the terminal at the solenoid.

Looking good Mike,

thanks for chiming in and helping out on the post.

Later on today I hope to have a measurement of the voltage drop across the cable as so many asked for.