Battery Cable Length?
05-26-2016, 08:17 PM
#106
Rennlist Member
I understand the length of 12.3' for the battery cable is for the S4. Any idea what the length is for my 1986.5 S3?
My idea was to have a 12.5' cable made up of 1 AWG marine battery cable with a positive top post terminal on one end and a 3/8" hole lug on the other.
Seth K. Pyle
My idea was to have a 12.5' cable made up of 1 AWG marine battery cable with a positive top post terminal on one end and a 3/8" hole lug on the other.
Seth K. Pyle
05-27-2016, 03:09 PM
#107
Chronic Tool Dropper
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Seth --
Without direct knowledge, I'll speculate for you that the length of your cable will be no more than an inch or two less than the S4 cable if yours has single exhaust. Cars with dual exhaust use a shorter Group 48/H6 battery to allow room for the right side pipe to pass between the differential cover and the front of the battery box. That adds a few inches to the cable length vs the single-exhaust cars with the larger Group 49 battery.
The routing of the cable on my car doesn't leave a lot of opportunity to "loop" a couple extra inches of cable until you get forward to the starter end. There, the cable goes to the right at the crossmember, then loops back to the starter. The primary cable is wire-tied to the alternator/ABS/Jump Post cables including the #50 circuit wire. So while the extra couple inches are easy to manage, you'll do some creative dressing of the whole harness assembly at the crossmember to make it all pretty.
Given the option, I'd rather dress out the extra inch or two of cable than risk it being too short.
On mine, with the crimping tools available, I fitted the battery end clamp first and dressed it completely on the bench before installation. Then fed the starter end through the battery box gaitor on the bench, then the cable through the battery box hole and follow the routing the original one used. Secured the cable in the original channel and clamps, all the way forward to the cross member. I looped the unfinished end into position, loosely dressing the cable with temporary ties to determine the exact routing and length. Then untied it from the cross-member so I could pull the cable end out next to the car, fit the lug and dress the end with shrink sleeve. Then back in for permanent tie up and positioning.
I used some flexible sprinkler repair hose from Home Depot for the friction sleeve, installed over the cable to protect it where it turns from the frame rail to the cross-member behind the steering gear lines, and again where the cable passes the starter motor on the cross-member. Install the sleeve BEFORE you crimp and dress the starter-end lug, as the shrink sleeve is enough bigger than the cable insulation to make it impossible to slide the sleeve over.
Without direct knowledge, I'll speculate for you that the length of your cable will be no more than an inch or two less than the S4 cable if yours has single exhaust. Cars with dual exhaust use a shorter Group 48/H6 battery to allow room for the right side pipe to pass between the differential cover and the front of the battery box. That adds a few inches to the cable length vs the single-exhaust cars with the larger Group 49 battery.
The routing of the cable on my car doesn't leave a lot of opportunity to "loop" a couple extra inches of cable until you get forward to the starter end. There, the cable goes to the right at the crossmember, then loops back to the starter. The primary cable is wire-tied to the alternator/ABS/Jump Post cables including the #50 circuit wire. So while the extra couple inches are easy to manage, you'll do some creative dressing of the whole harness assembly at the crossmember to make it all pretty.
Given the option, I'd rather dress out the extra inch or two of cable than risk it being too short.
On mine, with the crimping tools available, I fitted the battery end clamp first and dressed it completely on the bench before installation. Then fed the starter end through the battery box gaitor on the bench, then the cable through the battery box hole and follow the routing the original one used. Secured the cable in the original channel and clamps, all the way forward to the cross member. I looped the unfinished end into position, loosely dressing the cable with temporary ties to determine the exact routing and length. Then untied it from the cross-member so I could pull the cable end out next to the car, fit the lug and dress the end with shrink sleeve. Then back in for permanent tie up and positioning.
I used some flexible sprinkler repair hose from Home Depot for the friction sleeve, installed over the cable to protect it where it turns from the frame rail to the cross-member behind the steering gear lines, and again where the cable passes the starter motor on the cross-member. Install the sleeve BEFORE you crimp and dress the starter-end lug, as the shrink sleeve is enough bigger than the cable insulation to make it impossible to slide the sleeve over.
05-27-2016, 09:48 PM
#108
Rennlist Member
Hello again, dr bob: The Red Witch is a dual exhaust S3. She does take the shorter battery. I have verified that the exhaust pipe does pass behind the differential cover.
I am taking your advice. A 13' 1AWG marine battery cable with top post terminal installed and covered in adhesive heat shrink has been ordered. As well as a couple of 1AWG 3/8" hole cable lugs, more heat shrink, and other knick knacks. I will stop by my local Lowe's and find some similar PCV sprinkler repair tubing.
I have just put in my latest parts order, which includes a Waytek 2AWG ground strap.
My intent is to follow this post and your instructions like a road map. Start off at the battery end, and route the cable up to the starter. Measure twice, cut one, and terminate the cable at the starter. I will borrow the two handed Armstrong manual cable terminal crimper from work for the starter end lug.
Thanks again for all the advice!
Seth K. Pyle
I am taking your advice. A 13' 1AWG marine battery cable with top post terminal installed and covered in adhesive heat shrink has been ordered. As well as a couple of 1AWG 3/8" hole cable lugs, more heat shrink, and other knick knacks. I will stop by my local Lowe's and find some similar PCV sprinkler repair tubing.
I have just put in my latest parts order, which includes a Waytek 2AWG ground strap.
My intent is to follow this post and your instructions like a road map. Start off at the battery end, and route the cable up to the starter. Measure twice, cut one, and terminate the cable at the starter. I will borrow the two handed Armstrong manual cable terminal crimper from work for the starter end lug.
Thanks again for all the advice!
Seth K. Pyle
05-27-2016, 10:56 PM
#109
I did this back in the 90's... start from the battery and go forward...
http://www.928sg.com/electrical.htm
http://www.928sg.com/electrical.htm
05-28-2016, 06:15 AM
#111
Rennlist Member
05-28-2016, 06:39 AM
#112
Rennlist Member
Hi Fred!
The original (+) top post battery cable terminal is long gone. In its place, I found a universal lead replacement terminal. The copper strands were a twisted mess of white corrosion. Plus, there was some melted lead from the heat of the high resistance.
A wire brush and way too much DeOxit D100 has made the cable and terminal serviceable. But, they are quite ugly.
Replacement is the only cure.
Seth K. Pyle
The original (+) top post battery cable terminal is long gone. In its place, I found a universal lead replacement terminal. The copper strands were a twisted mess of white corrosion. Plus, there was some melted lead from the heat of the high resistance.
A wire brush and way too much DeOxit D100 has made the cable and terminal serviceable. But, they are quite ugly.
Replacement is the only cure.
Seth K. Pyle
05-28-2016, 06:57 AM
#113
Rennlist Member
Hi Fred!
The original (+) top post battery cable terminal is long gone. In its place, I found a universal lead replacement terminal. The copper strands were a twisted mess of white corrosion. Plus, there was some melted lead from the heat of the high resistance.
A wire brush and way too much DeOxit D100 has made the cable and terminal serviceable. But, they are quite ugly.
Replacement is the only cure.
Seth K. Pyle
The original (+) top post battery cable terminal is long gone. In its place, I found a universal lead replacement terminal. The copper strands were a twisted mess of white corrosion. Plus, there was some melted lead from the heat of the high resistance.
A wire brush and way too much DeOxit D100 has made the cable and terminal serviceable. But, they are quite ugly.
Replacement is the only cure.
Seth K. Pyle
Makes one wonder what some folks do to these poor cars. When you come to replace the culprit do post some pics- plenty of learning for all of us.
Thanks to this thread being resurrected and noting Dr Bob's experience, I went into my earth strap and as stated earlier, found it was halfway through the cooper braid at the chassis end. A new strap is currently on its way.
Yesterday I did a little experiment on the existing strap. Tried an old trick on it by immersing the oxidised broken strands in a mixture of vinegar and salt for 20 minutes. The copper looked like new and I could clearly see all the broken strands. Compressed it all in the wooden jaws of my Black and Decker work mate, donned one of my wife's oven mitts and heated the damaged area over the gas hob. Ran a pile of self fluxing solder into the failed area, dunked it in water and it looked like new. Chucked it into the car and the starter motor turned over like Usain Bolt out of the starting blocks. Could not believe the difference.
Hopefully you will get a similarly good result
Best wishes
Fred
05-28-2016, 12:31 PM
#114
Chronic Tool Dropper
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Battery Vent Tubing
Fred--
Interesting note on ground strap damage at the chassis end. For most, the problem is at the battery end, where there is exposure to corrosive fumes from the battery when the vent piping isn't added.
For those playing at home:
The Group 48/H6 battery that's standard in the dual-exhaust cars is equipped with a handy vent port for fumes generated (sorry...) when the battery is charging. There are condensing chambers in the top of each cell to limit the carryover of acid, but they are not 100% effective. There will always be some acid in the vented fumes. So, it's a very simple task to connect a small hose to that vent port, and direct the fumes out of the battery area.
The last several batteries I've purchased have included a rubber hose/manifold that slides over the vent stub on the battery. You could use a piece of almost any hose for this: vacuum hose, fuel hose, emissions hose, whatever. The port size is 6mm or 1/4" OD, so any 1/4" hose will do. From that short connecting hose, I used a handy length of 1/4" OD plastic irrigation tubing. I wanted to have something rigid enough to stay open as it is installed. The tubing or whatever you use passes through the rubber gaitor/grommet/fitting at the front of the battery box, then turns down towards the ground behind the heat shield for the battery box. I cut the tubing off an inch or so below the bottom of the battery box, so any carryover in the fumes won't affect the battery box from the outside.
This is a cheap five-minute fix that will save you a lot of misery as the car ages. You can use almost any 1/4" ID hose that you can stuff through the gaitor, so long as it isn't pinched closed at the pass-through point or bend down immediately forward of that spot.
We've witnessed more than several cars where the accumulation of acid in the battery well has lead (sorry again...) to severe corrosion damage of the well/battery box itself. Most severe needed a new battery box grafted in. Common is damage to all the fittings inside including hold-down brackets and cables, similar to what Seth has discovered in his car.
There's a potential (gotta choose better words...) for an explosiion in the battery well if there's ANY ignition source when the vent tubing is not installed. A byproduct of the charging process is the evolution of hydrogen and oxygen gasses, which accumulate in the closed battery compartment. Any loose connection or one with resistance high enough to make a lot of heat risks ignition of the explosive gas mixture. There are cases where the explosion has "merely" bowed the lid. I've seen other cases where the explosion included gases inside the battery itself, with catastrophic results.
Conclusion: There are many great reasons to add the vent plumbing to your battery and battery well. It's getting to be summer driving season, so a check of all the connections and wiring in there is a Good Idea, including a thorough cleaning and inspection of connections and cables. Lots of little sniggly symptoms amazingly disappear when the cables are fresh and connections including ground points are clean.
Interesting note on ground strap damage at the chassis end. For most, the problem is at the battery end, where there is exposure to corrosive fumes from the battery when the vent piping isn't added.
For those playing at home:
The Group 48/H6 battery that's standard in the dual-exhaust cars is equipped with a handy vent port for fumes generated (sorry...) when the battery is charging. There are condensing chambers in the top of each cell to limit the carryover of acid, but they are not 100% effective. There will always be some acid in the vented fumes. So, it's a very simple task to connect a small hose to that vent port, and direct the fumes out of the battery area.
The last several batteries I've purchased have included a rubber hose/manifold that slides over the vent stub on the battery. You could use a piece of almost any hose for this: vacuum hose, fuel hose, emissions hose, whatever. The port size is 6mm or 1/4" OD, so any 1/4" hose will do. From that short connecting hose, I used a handy length of 1/4" OD plastic irrigation tubing. I wanted to have something rigid enough to stay open as it is installed. The tubing or whatever you use passes through the rubber gaitor/grommet/fitting at the front of the battery box, then turns down towards the ground behind the heat shield for the battery box. I cut the tubing off an inch or so below the bottom of the battery box, so any carryover in the fumes won't affect the battery box from the outside.
This is a cheap five-minute fix that will save you a lot of misery as the car ages. You can use almost any 1/4" ID hose that you can stuff through the gaitor, so long as it isn't pinched closed at the pass-through point or bend down immediately forward of that spot.
We've witnessed more than several cars where the accumulation of acid in the battery well has lead (sorry again...) to severe corrosion damage of the well/battery box itself. Most severe needed a new battery box grafted in. Common is damage to all the fittings inside including hold-down brackets and cables, similar to what Seth has discovered in his car.
There's a potential (gotta choose better words...) for an explosiion in the battery well if there's ANY ignition source when the vent tubing is not installed. A byproduct of the charging process is the evolution of hydrogen and oxygen gasses, which accumulate in the closed battery compartment. Any loose connection or one with resistance high enough to make a lot of heat risks ignition of the explosive gas mixture. There are cases where the explosion has "merely" bowed the lid. I've seen other cases where the explosion included gases inside the battery itself, with catastrophic results.
Conclusion: There are many great reasons to add the vent plumbing to your battery and battery well. It's getting to be summer driving season, so a check of all the connections and wiring in there is a Good Idea, including a thorough cleaning and inspection of connections and cables. Lots of little sniggly symptoms amazingly disappear when the cables are fresh and connections including ground points are clean.
05-28-2016, 12:51 PM
#115
Rennlist Member
Bob,
Mine was not too bad at the battery end. the batteries we get this end are generally of the sealed type and have no vent pipe- why I have no idea. Everything in the battery box area looks fine thank goodness!].
The only problem over here is that batteries rarely last more than two years no matter how much you pay or what make you purchase. I regularly recommend folks put a sheet of rubber over the positive post to ensure nothing there goes to earth- there is not much clearance.
My party piece many years ago in the late S4 was when I forgot to put the hold down bracket back in. Was driving along night time on a busy expressway, went over a bump and everything went dead, lights, indicators engine, windows - the while job lot! Just getting across the carriage way to the side of the road was very difficult at night time when you are deaf dumb and blind! Gradually rolled to a halt and went to take a look at the battery- the damm lid was welded to the battery positive post with nicely singed paint above the weld point! First thing I ever welded in my life and it worked! To get the battery out i have to drill a series of small holes to perforate the lid but the plus side was to see just how close everthing was to it.
Post script to this the battery was nearly new so i cleaned up the top of the post where it was welded and took the battery back to the shop with the warranty card telling them "there appeared to be something wrong with the battery". See- honesty does pay - they gave me a new one.
Rgds
Fred
Mine was not too bad at the battery end. the batteries we get this end are generally of the sealed type and have no vent pipe- why I have no idea. Everything in the battery box area looks fine thank goodness!].
The only problem over here is that batteries rarely last more than two years no matter how much you pay or what make you purchase. I regularly recommend folks put a sheet of rubber over the positive post to ensure nothing there goes to earth- there is not much clearance.
My party piece many years ago in the late S4 was when I forgot to put the hold down bracket back in. Was driving along night time on a busy expressway, went over a bump and everything went dead, lights, indicators engine, windows - the while job lot! Just getting across the carriage way to the side of the road was very difficult at night time when you are deaf dumb and blind! Gradually rolled to a halt and went to take a look at the battery- the damm lid was welded to the battery positive post with nicely singed paint above the weld point! First thing I ever welded in my life and it worked! To get the battery out i have to drill a series of small holes to perforate the lid but the plus side was to see just how close everthing was to it.
Post script to this the battery was nearly new so i cleaned up the top of the post where it was welded and took the battery back to the shop with the warranty card telling them "there appeared to be something wrong with the battery". See- honesty does pay - they gave me a new one.
Rgds
Fred
05-29-2016, 03:48 AM
#116
Rennlist Member
FredR: I will post some photos when I do the deed. I did not take photos of the corroded cable, mainly due to embarrasment. I do have couple of photos of the conductors after I drowned them in DeOxit D100.
That sounds like a neat trick. Probably cost effective, too, given that I paid almost $75 for a new Porsche ground strap.
Nice party trick. That had to hurt. Hearing stories like this makes me definitely want to keep the plastic terminal covers in place on the battery.
dr bob: I agree on the cleanliness of the battery and battery box. I am going to go to town on mine again with hot water and baking soda. I am considering a product called 'battery mat' from years ago. Not sure yet. I am also considering repainting the bottom of the battery box. Possibly undercoating or something along those lines. I am making this up as I go.
I am definitely making a longer battery vent line. The one I have rigged up now just goes an inch out of the battery box. I will get longer 1/4" tubing and route it similar to what you have suggested.
Thanks!
Seth K. Pyle
That sounds like a neat trick. Probably cost effective, too, given that I paid almost $75 for a new Porsche ground strap.
Nice party trick. That had to hurt. Hearing stories like this makes me definitely want to keep the plastic terminal covers in place on the battery.
dr bob: I agree on the cleanliness of the battery and battery box. I am going to go to town on mine again with hot water and baking soda. I am considering a product called 'battery mat' from years ago. Not sure yet. I am also considering repainting the bottom of the battery box. Possibly undercoating or something along those lines. I am making this up as I go.
I am definitely making a longer battery vent line. The one I have rigged up now just goes an inch out of the battery box. I will get longer 1/4" tubing and route it similar to what you have suggested.
Thanks!
Seth K. Pyle
05-29-2016, 07:30 PM
#117
Chronic Tool Dropper
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Fred--
Some batteries are "sealed", in that you can't get the caps up to check electrolyte. But if they charge, they outgas. And the gas is much larger specific volume than the liquid. So it has to vent the fumes somewhere.
Some batteries are "sealed", in that you can't get the caps up to check electrolyte. But if they charge, they outgas. And the gas is much larger specific volume than the liquid. So it has to vent the fumes somewhere.
05-30-2016, 03:06 AM
#118
Rennlist Member
The mystery to me is not the outgas but how and where it gets out. One imagines they have some kind of breather system, possibly allowing a very small amount of positive pressure to exist inside but...?
In my case I have never seen any obvious signs of corrosion going on- having said that what is the betting my battery will drop onto the deck next time out?
Rgds
Fred
05-30-2016, 12:43 PM
#119
Chronic Tool Dropper
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Coincidentally, I was changing UPS batteries yesterday, and found the old ones had "swollen". Almost to the point where getting them out of the holder was a bit of a challenge. These are "Sealed Lead Acid" batteries per the manufacturer. Useful life in UPS service is normally two years, these were getting close to three years and complaining.
So I guess I know that are such things as truly sealed batteries. The outgas vapors just made the whole case a bit bigger.
So I guess I know that are such things as truly sealed batteries. The outgas vapors just made the whole case a bit bigger.
01-23-2017, 01:00 AM
#120
Rennlist Member
Related to above, does anyone have a length for an '82 US?
I've measured mine twice - one directly against the cable and one measuring a string I used to follow the curves of the cable. I'm questioning my results, as there are a few areas in it where there is some solid sleeving over the cable which leads to a bends which are difficult to measure (and can't be fully straightened out).
I've gotten 136", center of lug to center of terminal, or 11'4". This is ~7" shorter than the lengths stated for the 86's...although I did my best to compensate for the bends in the measurement, I'm concerned that I've got a bunch of unaccounted slack in there.
Anyone have field numbers from an '82 (or have definitive length for one)?
Thanks!
I've measured mine twice - one directly against the cable and one measuring a string I used to follow the curves of the cable. I'm questioning my results, as there are a few areas in it where there is some solid sleeving over the cable which leads to a bends which are difficult to measure (and can't be fully straightened out).
I've gotten 136", center of lug to center of terminal, or 11'4". This is ~7" shorter than the lengths stated for the 86's...although I did my best to compensate for the bends in the measurement, I'm concerned that I've got a bunch of unaccounted slack in there.
Anyone have field numbers from an '82 (or have definitive length for one)?
Thanks!