Battery terminal corrosion

[LEECH21]

I have been getting a bad connection on my starting battery for my Crestliner. I noticed quite a bit of corrosion. What do you guys recommend to clean it up? Thanks - Jesse

[RebelSS]

Good ol' white vinegar, and a battery terminal brush. Or, you can use baking soda and a wet toothbrush, either will work. Be careful of the runoff; it's mildly corrosive. Check all connections for cracks or breaks. I then smear my connections with Dielectric grease and tighten securely, with a stainless nut and washer. Forego the older "wingnut", if that's what you have. You should be good to go.

[CaptainMusky]

Coca Cola will do wonders.

I have used some battery terminal cleaner with great results but it gets a bit messy. Once clean put some dielectric grease on there and you will avoid having this problem later.

[gunner55]

I use baking soda along with a wire brush on the posts,sometimes a jackknife or a fine file on wires.The die-electric grease is a must & check them at least once,about 1/2 way through the season.

[Down Deep]

I use a rag to twist off the white stuff and then use a battery terminal brush to clean the terminals to new condition. I also file my contacts with a flat file. Both should be cleaned. You can get a terminal brush at any auto parts store.

[h8go4s]

These small wire brushes work great. Any hardware store should have them. They're a little bigger than a toothbrush, easy to get into tight spaces. No need to mess around with baking soda, etc. Just shine up the terminals, vacuum up the dust and go fishing.

http://www.homedepot.com/p/Lincoln-Elect...KH580/100341131

[Finns]

Go with RebellSS advice.

[BobT]

I have found this tool to be about the best tool for maintaining my battery posts and clamps.

Little tip:

Rotate clockwise, never counter-clockwise. This is true for both the post and the clamp brush. The bristles are angled and if you rotate counter-clockwise it will distort them.

Apply a thin layer of dielectric grease to the terminal and post before clamping back on. This will assure a good solid connection. That corrosion you see is caused by arcing in the clamp and the grease will fill air gaps between the post and the clamp, reducing the potential for arcing.

[LEECH21]

Thanks guys. So any gap between the clamp and the battery terminal will cause arching which leads to corrosion? I disconnect my starting battery after every use, otherwise my radio pulls a little power and drains my battery when my boat is in my garage. Would you recommend installing a master kill switch so I wouldn't have to disconnect and reconnect all the time? I assume this would help with the arching. Also, how hard would it be to install such a switch?

[Kyhl]

The electronics in newer motors will also drain starting batteries when they sit for long periods of time. I leave it hooked up and put a charger on it for an hour each week to top it off, or I recharge it over night before using.

[BobT]

Thanks guys. So any gap between the clamp and the battery terminal will cause arching which leads to corrosion? I disconnect my starting battery after every use, otherwise my radio pulls a little power and drains my battery when my boat is in my garage. Would you recommend installing a master kill switch so I wouldn't have to disconnect and reconnect all the time? I assume this would help with the arching. Also, how hard would it be to install such a switch?

If it is just your radio, does your boat have an accessory switch? Maybe you could rewire the radio to it.

Batteries will lose charge just sitting on a bench over time. This not unusual. I have a ProMariner on-board charger and I just leave mine plugged in when it is at home. Always fully charged and ready when I need it plus the charger has a built-in reconditioning feature that refreshes the battery once a month so I don't have to periodically cycle power to the charger.

[Jeremy airjer W]

Apply a thin layer of dielectric grease to the terminal and post before clamping back on. This will assure a good solid connection. That corrosion you see is caused by arcing in the clamp and the grease will fill air gaps between the post and the clamp, reducing the potential for arcing.

I would recommend applying the di-electric grease after the terminal has been put back on to the post and tightened. Di-electric grease is non conductive.

I had a car get towed in a few years ago for a no crank complaint. The customer had just replaced the battery because of age. the car started and ran fine prior to installing the new battery. Upon opening the hood the terminals where well coated in di-electric grease. A quick test revealed power at the battery terminals but no power at the battery connectors. The terminals where removed and all the grease cleaned off. Once reinstalled the car started just fine. The customer was pretty disappointed that his good intentions cost a tow and a diag.

The moral of the story, a little goes a long ways!

[low277]

Once the connections are clean, I use a oxide inhibiting compound that is made to be used on aluminum wire connections. I have been using this stuff for about 25 years now and it works good.

[BobT]

I would recommend applying the di-electric grease after the terminal has been put back on to the post and tightened. Di-electric grease is non conductive.

I had a car get towed in a few years ago for a no crank complaint. The customer had just replaced the battery because of age. the car started and ran fine prior to installing the new battery. Upon opening the hood the terminals where well coated in di-electric grease. A quick test revealed power at the battery terminals but no power at the battery connectors. The terminals where removed and all the grease cleaned off. Once reinstalled the car started just fine. The customer was pretty disappointed that his good intentions cost a tow and a diag.

The moral of the story, a little goes a long ways!

This is interesting and I haven't really given it too much thought before. I haven't checked lately but the couple times I installed service entrances on my buildings using aluminum SE cable, I recall the NEC requiring dieelctric grease be applied to to protect against oxidation. Why would this be done if it potentially adds an insulating value?

[delcecchi]

What Jeremy said surprised me too. Did the clamps get tightened down after the grease? Or was this one of those goofy GM side terminal things with no post?

[Finns]

Found this on the 'Net'.

It is non-conductive, but when you slide the connectors together there is metal-to-metal contact and the grease gets displaced but the area around connector is protected from moisture. If the grease was conductive it would be too easy to get "bleed" from one pin to another in a connector if the grease got hot and liquified and spread.

This was in reference to male/female connections but I think it still somewhat applies to this scenario.

For what it is worth.

[RebelSS]

I have always cleaned my terminals as stated in my previous post, then put a drop of light oil such as gun oil, 3 in 1, etc on the top of the terminal, and rubbed it around the sides with my finger, leaving a very light coating. Install "clamp", then I put the Silicone (Dielectric) grease on and around terminal. When I was a mechanic way back in the early 70's, white lithium grease was used this way, long before the Silicone's came out. Another trick I used to "seal" the terminal, was on a warm day, I put a blob of that black rubber "Shoe Goo" on top of the post, and let it run down and completely cover terminal. Easy to pull off if you had to, and jumper cables would bite through it. Old school tips.

[Finns]