# Battery Terminals Never Tight Enough



## dougp23

My wife has a VW Jetta, 2005. At least 3 times in the last year or so, you will go to start the car and get nothing. Not a click, nothing. No chimes, no lights. Pop the hood, and move the wires on the battery, and they won't move, they are nice and snug.
Get out your sockets, and REALLY tighten those bolts on the battery and it starts right up....

So I have put a small socket wrench with a 10mm socket on it in her glove box. I am just wondering can I over tighten the terminals and maybe break a post on the battery? I always figured as long as the cable was even touching the post, even gently, would be enough...


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## Windows on Wash

Pull the cables off, clean up the mating surfaces, apply dielectric between them, reassemble, cover with dielectric grease.


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## lenaitch

A strong battery should not be affected by a seemingly tight connection. You might have a layer of dirt, corrosion or oxidization on either the battery or the clamp. Try taking some steel wool, emory cloth or even sandpaper to both the posts and the clamps until they are shiny.

I doubt you could damage the posts or clamps by reefing down on them. Band type clamps can only get so tight. I suppose you could possibly damage the clamp bolts and possibly damage the posts if your exuberance somehow torqued them.

+1 on dialectric grease.


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## r0ckstarr

If you're on the side of the road, and have no access to dielectric grease, motor oil works. I had a problem with corrosion that kept leaving me with a truck that wouldn't start. I wire brushed the corrosion off, then pulled out the dip stick and wiped some oil onto the terminals and clamps. Haven't had an issue since.


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## clarenceboddick

A ghetto trick is to install a screw between the post and terminal to make a tight connection. You can also buy terminal shims.


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## DexterII

Don't know which type of clamp you have, but, before attaching it to the battery, tighten it to make sure that it is actually closing far enough to actually tighten on the terminal. Corrosion, electrolysis, whatever will eat away at the terminals over time, which may mean that the clamp needs to be tighter than it originally was. Meanwhile the threads on the bolt are corroding, so that it feels like the clamp is getting tight when it's actually just the bolt that is getting tight.


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## getrex

Excessive tightening will shorten the life of the terminals. New ones are really cheap. Sand up the posts and put on the new ones, with the grease as mentioned above. I have heard that WD-40 works as well.

Some options:

http://m.autozone.com/batteries-starting-and-charging/battery-terminal?searchText=battery+terminal

I bought the first one for my car. Nice and easy on and off.


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## ChuckF.

If it's a lead terminal you can overtighten it to the point that the lead stretches and the two sides that the bolt go through end up meeting. Then you definitely need a shim. 

Clean them and get the battery terminal grease. Comes in little tubes or maybe a one-use pouch like fast-food mustard.


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## ukrkoz

clarenceboddick said:


> A ghetto trick is to install a screw between the post and terminal to make a tight connection. You can also buy terminal shims.


Yes, it is.
Cable clamps must be installed flush with battery upper surface.
What I did was to then drive a self tapping screw at the angle right into the clamp edge and battery terminal. Fortunately it's very soft metal, so it goes in easy, as far as small pilot hole is drilled. Going at about 45 degree angle down, screw head works as an anchor and pulls terminal down and sets it solid. 
Also, it's a VW. Do you have a flat plastic plate with some electronics mounted on top of battery terminals? If yes, wait for that to go bad any time.


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## Brainbucket

VW Battery terminal ends are crappy. After a while they stretch. I DO NOT put ointment between battery posts and terminal ends. It gets hot and then the residue creates resistance. Wash it with water as that dilutes the acid. Clean and put them on dry. If the corrosion comes back, look up the battery cable wire and the corrosion climbs up the wire and if you don't cut out the corrosion, it will come back. New cables are generally the only way to solve that problem. Temporary terminal ends work but they are temporary. I have had those on cars for a long time so the corrosion will be your guide to replacement. Don't tell anyone but I have used screws.:surprise:


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## papereater

Windows on Wash said:


> Pull the cables off, clean up the mating surfaces, apply dielectric between them, reassemble, cover with dielectric grease.


Dielectic grease is not designed to be put BETWEEN elec contacted surfaces. It is an insulator, NOT a conducting medium. This is one of the most common myths of the use of this grease. Between battery posts, it will interfere with the voltage conductivity to the battery cables......


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## clarenceboddick

ukrkoz said:


> Yes, it is.
> Cable clamps must be installed flush with battery upper surface.
> What I did was to then drive a self tapping screw at the angle right into the clamp edge and battery terminal. Fortunately it's very soft metal, so it goes in easy, as far as small pilot hole is drilled. Going at about 45 degree angle down, screw head works as an anchor and pulls terminal down and sets it solid.
> Also, it's a VW. Do you have a flat plastic plate with some electronics mounted on top of battery terminals? If yes, wait for that to go bad any time.


I think VW started using the stupid above battery harness with the 4th gen Golf/Jetta (A-4 Chassis) cars. I don't remember if the New Beetle and Passat uses them. They are a stupid idea and a source of problem. Not too hard to remove it and rewire it properly.


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## Brainbucket

Dielectric grease is a non-conductive, silicone-based grease that's designed to seal out moisture and prevent corrosion on electrical connectors. It also disrupts the flow of electrical current, which makes it good for lubricating and sealing the rubber parts of electrical connectors. It's commonly used in automotive spark plug wires, recreational and utility vehicles, and electrical systems in aircraft. Also it helps on corrosion between aluminum and copper connections in electrical applications. :vs_cool:


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## papereater

Brainbucket said:


> Dielectric grease is a non-conductive, silicone-based grease that's designed to seal out moisture and prevent corrosion on electrical connectors. It also disrupts the flow of electrical current, which makes it good for lubricating and sealing the rubber parts of electrical connectors. It's commonly used in automotive spark plug wires, recreational and utility vehicles, and electrical systems in aircraft. Also it helps on corrosion between aluminum and copper connections in electrical applications. :vs_cool:


Right. And if everything in your car/whatever is in tip top shape, you probably don't even need it.


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## Windows on Wash

Brainbucket said:


> VW Battery terminal ends are crappy. After a while they stretch. I DO NOT put ointment between battery posts and terminal ends. It gets hot and then the residue creates resistance. Wash it with water as that dilutes the acid. Clean and put them on dry. If the corrosion comes back, look up the battery cable wire and the corrosion climbs up the wire and if you don't cut out the corrosion, it will come back. New cables are generally the only way to solve that problem. Temporary terminal ends work but they are temporary. I have had those on cars for a long time so the corrosion will be your guide to replacement. Don't tell anyone but I have used screws.:surprise:





papereater said:


> Dielectic grease is not designed to be put BETWEEN elec contacted surfaces. It is an insulator, NOT a conducting medium. This is one of the most common myths of the use of this grease. Between battery posts, it will interfere with the voltage conductivity to the battery cables......


Learn something new every day. I am guessing it hasn't proved to be a problem on my vehicles because they have tight tolerances. It definitely keeps the corrosion down around the posts without the sulfuric acid fumes reacting with the lead posts.


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## Windows on Wash

papereater said:


> Right. And if everything in your car/whatever is in tip top shape, you probably don't even need it.


I always use it on spark plug boots and have had great success getting them off without breaking them. I think it is great in those applications as well as what I mentioned previously.


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## lenaitch

http://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm

And from Wiki:

*Dielectric grease[edit]*

Dielectric grease is electrically insulating and does not break down when high voltage is applied. It is often applied to electrical connectors, particularly those containing rubber gaskets, as a means of lubricating and sealing rubber portions of the connector without arcing.
A common use of dielectric grease is in high-voltage connections associated with gasoline engine spark plugs. The grease is applied to the rubber boot of the plug wire. This helps the rubber boot slide onto the ceramic insulator of the plug. The grease also acts to seal the rubber boot, while at the same time preventing the rubber from becoming stuck to the ceramic. Generally, spark plugs are located in areas of high temperature and the grease is formulated to withstand the temperature range expected. It can be applied to the actual contact as well, because the contact pressure is sufficient to penetrate the grease film. Doing so on such high pressure contact surfaces between different metals has the advantage of sealing the contact area against electrolytes that might cause rapid deterioration from galvanic corrosion.
Another common use of dielectric grease is on the rubber mating surfaces or gaskets of multi-pin electrical connectors used in automotive and marine engines. The grease again acts as a lubricant and a sealant on the nonconductive mating surfaces of the connector. It is not recommended to be applied to the actual electrical conductive contacts of the connector because it could interfere with the electrical signals passing through the connector in cases where the contact pressure is very low. Products designed as electronic connector lubricants, on the other hand, should be applied to such connector contacts and can dramatically extend their useful life. Polyphenyl Ether, rather than silicone grease, is the active ingredient in some such connector lubricants.
Silicone grease should not be applied to (or next to) any switch contact that might experience arcing, as silicone can convert to silicon-carbide under arcing conditions, and accumulation of the silicon-carbide can cause the contacts to prematurely fail. (British Telecom had this problem in the 1970s when silicone Symel® sleeving was used in telephone exchanges. Vapor from the sleeving migrated to relay contacts and the resultant silicon-carbide caused intermittent connection.)


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