Starter cable gage needed

Im using CSR starter on my 511. Had trouble with it disengaging and engaging while rolling engine over. I want to replace the starter cable which runs from cut off switch to starter. Currently have 6 gage cable, want something larger. CSR says i need 00 gage. Do i really need that huge cable? Gonna change out the battery as well.

Yes, need at least 0 if not 00. Wait till the motor's good and hot and you'll find out real quick need all the amps the battery can deliver. 0 or 00 will be peace of mind that it will crank when ever.

I use 2ga on everything for the main cable. Master switch to a junction in the firewall area. Distributed from there to starter relay, switch panel, etc. Good 2ga, fine strand welding cable. Big motors, high compression, whatever. Lighter, easier to work with. Never a problem. Never an issue st the track. All the chassis guys - Bickel, RJ - sell the same thing for their stuff. Don't use a junk starter.

Dave,

6ga? Stock cables are 4ga IIRC

Simple deal, larger wire is more efficient. Most vendors sell wire that is undersized for the applications. If you street drive the car, larger wire is better especially in hot start situations.

I sell 1/0 battery cable and they are stout and do the job with minimal voltage drop.

Weight is not an issue. A 1/0 wire of 15ish feet weighs about 3 pounds more than a 2 gauge wire of same length.

A 15' 2 ga wire weighs 4.2 pounds
Same in 1/0 is 6.9 pounds

You could do 2/0, not really a big step up from 1/0

Are you saying the csr starters are no good? I used same starter on my small and never an issue. It only disengages while starting hot, never cold.

Your cable is most definitely too small. I used 00 welding cable when I mounting the battery in the trunk.

It might be 4gage. Bought 20yrs ago from summit in a battery relocate kit. Does look vety big. I have 2gage on ground side to engine block.

Some of those kits had aluminum wire in them. Also, the strands were fairly big. IIRC there were only 6-8 strands of wire in the cable.


I had something similar and fought starting issues. The 00 welding cable solved that.

Never had an issue til now. BB must be lot harder to spin when hot. Not sure but i thought this CSR starter was rated at 3hp

I don't know. Never used one. I was just making a general statement - starters are not all the same and they wear out. If it's acting like your OP description, I would suspect something is wrong with it.

Ill update the cable and half worn out battery first. Still have a factory mini i can throw in if need be.

Easy test if you can access the starter, run a jumper cable from battery too starter stud. If it kicks over easier, you know what the issue is! Use anything that can upsize the size of the circuit, even 2 12ga runs of wire would help.

Upgrade both side of the circuit, ground cable is just as important as the positive side.

Most of those trunk kits use a 2ga wire. Not sure about them if they are really old. In the 80's I never used that stuff, always 1/0 or 2/0 welding cables. My stuff starts even when smoking hot while hot lapping.

thanks. The cable's too small and the battery is on its way out and starter is fairly new. I get to the welding shop and see what I can get.

There are usually a couple different style of welding cable.
TPE and EPDM jacketed

I use EPDM as the jacket is better with oil resistance. There is also a new SGR wire that appears to be EPDM welding wire with a SAE rating.

It all has to do with voltage drop. Length/diameter ratio vs available battery capacity. However the the starter Kicking out doesn't sound like a lack of watts to the starter. Does the starter continue to spin without being engaged to the ring gear? If so that sound more like a mechanical internal starter or alignment issue.
Doug

Yes it does. It disengages while spinning engine and engage while i'm still on the start button, grinding on the ring gear. I know the battery is on its way out as it will no longer hold capacity after being run dead 5 times. So, i was thinking new larger cable and a new battery to start. If that doesn't do it, than i can put my old factory mini back on and try. The CSR starter is barely used.

I have a suggestion, why don't you gather some data and determine what is wrong before you start replacing things?

you can do a simple (and I mean simple!) voltage drop test and know which components need to be fixed.

I helped a guy out that had changed his battery, cables and starter. After changing it all out his car still started poorly. took me about 3 mins to find he was dropping 2.2 volts thur his main battery cutoff and another .5 volt from his ground.

If you don't know where your voltage loss is occurring you are guessing.
try it! you will be surprised how easy it is. (see my sig)

https://board.moparts.org/ubbthreads/ubbt...tml#Post2342153


Joe

didn't monte always recommend a "floating" ground ?

I understand what yur sayin, but i have already pin pointed part of the problem. The battery now shows 50% capacity on my charger and the cable is already known to be too small. Those parts are already needed, so why not install them and go from there? It needs those parts anyway, not like its wasted money. The starter relay is getting old as well, think i'll switch it out as well. This will be a good project as i would like a new battery box and a repaint in the truck as well. Thanks

What is the rating of the master switch? Does it have copper or silver contacts? How old is it? What is the voltage drop across the contacts under a high load? I have fixed multiple electrical issues by changing out old or cheap switches.

Dont know, but i can check. Maybe 10yrs old longacer switch. What should all the measures be to get a passing grade?

I've checked them with an ohm meter and caught bad ones. But it's a big difference when trying to run a few hundred amps through it. I usually just change them out occasionally or if an issue pops up. I would think a voltage drop test from the battery positive to the output stud of the main switch, while the starter is engaged, would show any issue with the switch.

Another reason I don't run my starter cable through the cut off. It's death by a thousand cuts killing them regardless of momentary rating. Sometimes they will weld themselves in the on position and the switch won't work at all.

A test that only requires a wrench, hook the battery up to the downstream/starter side of the cut off and test it. Turn the key. If it does the same action as when going through the switch, you can scratch it off the list.

Ok, ill check that.

Dave take a few mins to go to youtube and look up "voltage drop test". once you understand how to test, your electrical problems will go away and any that come up can be solved quickly. this is a skillset that every DIY'er should know how to use.

also the correct answer is "0" voltage loss across the switch.

climbing down off of soap box

Joe

Ok. Thanks for that.

Correct, any resistance across a switch, replace it.

Was looking at a Ron Francis catalog this morning for something and ran across his trunk mount battery cable kit for street rods with EFI, power accessories, etc. 1ga.

I would , and do , use either #1 or #0 for my trunk mounted batteries depending on the compression and if it is a street car or race only car.
#0 on race only cars with multiple grounds also

I just picked up my wire, 1/0 to the starter and #4 for the charge wire and to the feed up front. Also my starter wire will not go through my disconnect switch.

Most tech guys track test is to flip the switch to off and have you try and crank. Better make sure it shuts the starter solinoid feed circuit off if the starter main feed doesn't go through the switch.
Doug

It will.

Rule book says master switch must shut off all electrical functions. Ever have a starter "stick", solenoid jam and keep the starter engaged? I have. How you going to fix that when the starter is hooked directly to the battery? If running the starter smokes your master switch, you need a better master switch.

My Longacre master switch is getting very old at this point. Still shuts everything off.

I used aircraft wire, it has like 120 strands in it in a 1/0 size, and it can handle the amperage of a standard wire that is 1 size larger. Tim