Those darn Battery Terminals!

[pjsmetana]

The day after Christmas my Dad came over to hang out with me. I decided to take him for a ride in my Spitfire, as hes only ever seen pictures of it. When we stopped for gas I turned the key to find I had barely enough power to turn the starter. Last time I encountered this I just popped the bonnet and tapped the battery terminal then tried to crank it again. Well, this time I tapped it, tried, and nothing. Then I tightened the negative terminal, as thats been the problem child since day 1, and still nothing. Even after tightening the terminal I could just grab it and pull it straight off. My lead terminals are only about 6 months old but seemed to have stretched terribly.

My fix as of yesterday morning was new BRASS terminals and a new red top Duralast battery with a 7 year warranty.

Is my fix good enough to keep this from happening again or is there something else I need to try? I keep a tender on the battery and clean the terminals regularly with baking soda/distilled water and a tooth brush.

Anyone else have this sorta issue? How did you keep it from happening again?

 

[NutmegCT]

Pete - in 30 years of driving I've never had shrunken terminals. Maybe you live in a highly magnetic geologic area ... ?

I have seen guys have to "tap" with a hammer infrequently, but that's often due to having a loose terminal that gets corrosion inside.

Never (fortunately) had that problem either. When I install a new battery (or cable set), I just clean/wire brush the terminal and the post, tighten the terminal around it (be sure you use the correct terminal on the correct post - one is usually larger than the other), then maybe spray with that red "anti-corrosion battery terminal" stuff you can find just about anywhere.

Edit: I envy you taking your dad for a ride in your LBC. Unfortunately I never had the chance.

Hang in there.
Tom

 

[NickMorgan]

If you put some anti-corrosion grease onto the terminals and clamps you should never have to remove them or clean them. You know that the positive and negative terminals are different sizes? Maybe you had two positive clamps?
Having said that, I keep the earth clamp slightly loose on my TR, so that with a twist I can remove it without the need for a spanner. I have had too many electrical incidents in the past requiring rapid disconnection of the battery!

 

[tomgt6]

The other thing to test is if your alternator is working. It seems funny that the battery was dead. The other thing I have done was to buy something like this so when the car is parked for some time I just turn the battery off.

https://cgi.ebay.com/2-new-Auto-truck-Bat...=item3a563d1522

 

[pjsmetana]

I envy you taking your dad for a ride in your LBC. Unfortunately I never had the chance.

My Great Grandmother is still around too. I seemed to be quite lucky with nearly all of my family living easily past 100.

Maybe you had two positive clamps?

Possible, but doubtful. I looked at that possibility when I purchased the brass ones, but there was only 1 size. I had to pry the + side a little wider for a proper seat.

The other thing to test is if your alternator is working.

I'm sure it is. Its part of my 'pre-drive' checks. I also use a maintainer. I am, however, unsure of the age of the battery. It was probably due to be changed anyways.

Pete - in 30 years of driving I've never had shrunken terminals. Maybe you live in a highly magnetic geologic area ... ?

I had the car moved from MD to FL about a month ago. It was very cold in MD when it was picked up. Also, the garage I had it in was not climate controlled. My theory is that the expansion and contraction of the metal terminal, because of the climate change, was just enough to stretch the soft metal terminal. Although I'm not sure that 30F to 70F+ would be enough to do such a thing. I just hope the change to brass makes a difference.

 

[toysrrus]

Hi Pete,

I believe you solved your own problem by getting new Terminals and a Battery. Keep us posted.

Russ

 

[dklawson]

I've had battery terminal clamps break in half but not stretch. My thought was the same as Nick's that perhaps somehow you started with two of the larger diameter clamps. Regardless, your brass terminal should be a more permanent fix. The brass is likely to be attacked a bit more by battery acid so the anti-corrosion grease mentioned above is a very good idea.

 

[DougF]

Remember those felt rings that were commonly used around the base of battery terminals years ago? For a long time, I never understood their purpose.
The lead terminal and plastic battery case expand and contract at different rates when the battery heats and cools, allowing corrosive gasses to escape. The rings are treated with a substance that neutralized these gasses reducing the chances of corrosion.
The use of the felt rings along with a chemical protectant should keep your battery connections nearly corrosion free for a long time. Nothing is guaranteed, but you should see better battery performance.

 

[TR3driver]

The brass is likely to be attacked a bit more by battery acid

That's my candidate for understatement of the day!

 

[pjsmetana]

Remember those felt rings ...

Yep, Using them now. I wasn't before, but I most certainly am now.

The brass is likely to be attacked a bit more by battery acid

That's my candidate for understatement of the day!

So the brass might actually make it worse?? I could always get the gold kind with the massive set screws... ya know... the kind the big-stereo-boys use. There is also the steel kind that new cars use where the cable is crimped in and the terminal end wraps around. I don't particularly like the look of those, but I'll give them a go if the Brass ones fail too, and if you guys think the Gold ones are overkill.

 

[dklawson]

Sorry Randall.

Yes, the brass will be attacked quicker by the acid fumes than the lead will. I'm not sure that gold plated parts are that much better. Yes, the gold is inert, but the plating is very thin and once scratched doesn't offer a lot of protection to the underlying metal.

How about going to a local boat store and buying the heavy-duty marine battery cable clamps?

FWIW, I use those felt washers and I put a smear of dielectric grease on the terminals and inside the cable clamp before I tighten them in place.

 

[tomshobby]

I do not remember what kind of cable clamps came on my TR4 but my 67 GT6 came new with cables ends that were like little cups that fit over the battery posts and had a screw, about a #6, that fit in a hole and screwed into the top of the post. Had the car for several years and never had any corrosion around the connections.

 

[TR3driver]

Personally, I think you are solving a non-problem. You had some clamps that were defective or poor quality, that's all. Get some quality lead plated clamps, the kind that come integral with the battery cable (not the universal replacements that wholesale for about $.35 each) and sized for + or - and you should be good to go for many, many years.

The "new" one on the left has been in service since 2001 (when a starter misadventure melted the insulation on the previous cable); the one on the right must be at least 20 years old.

 

[pjsmetana]

How about going to a local boat store and buying the heavy-duty marine battery cable clamps?

FWIW, I use those felt washers and I put a smear of dielectric grease on the terminals and inside the cable clamp before I tighten them in place.

Yeah those are the clamps I'm referring to. I guess that means yes get them, if/when I have any more problems. I may do it anyways as I don't really care for the look of brass in my engine bay.

So, use that grease on the actual connection? I put it all over the outside like I've always done, but never on the actual electron transferring surface. Maybe thats why I've had continuing problems.

 

[dklawson]

What I'm using on most of my electrical connections in various wiring harnesses and on the battery terminals is actually Dow High-Vacuum Grease. (Not exactly in the auto parts store). It's a very thick, clear/opaque silicone grease. It has not caused me problems on any electrical connections. The dielectric grease at the parts store should behave similarly. Most of it will get "squished" and squeezed out of the contact area when you tighten the clamps. The stuff that gets squeezed out moves to the gaps and margins and (more or less) forms a wall keeping moisture out of the area that is in contact.

 

[prb51]

Since I went to a gel battery I've never had to clean the posts, batt about 4 years old...is that due to the sealed nature of the units.

 

[startech47]

Good stuff it is. I think I still have some on my fingers and I haven't used it for 26 years. A little goes a long way. Oh the days of designing semi-conductor process equipment. Thanks for stirring up the memories.