Battery replacement

[u/Routine_Adagio7496]

Hi I tried replacing my battery and got it out and put the new one in, connected the positive and went to the negative but I couldn’t get it on because my new battery has a slightly wider negative, I heard you can expand the terminal, but it is so old and rusty that it won’t expand at all, the battery was last changed 4 years ago before I owned the car. Should I buy a new negative clamp?

The car is a 2013 Honda civic es diesel

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[u/nabob1978]

You have the battery backwards probably.

In your first picture, the battery is turned opposite.

[u/djltoronto → u/nabob1978]

I hope this isn't the case, but based on that first picture, I don't know why they would Orient the batteries that way.

[u/Jargler2 → u/djltoronto]

In the first picture you can zoom in and confirm the sticker that you can see in the second picture is on the negative side so not backwards at least

I agree with another comment that’s further down make sure the nut is very lose and pry it apart slightly and confirm the plastic cover is off then wiggle it on

[u/RayjinCaucasian]

Can you confirm you took the protective cover off of the post?

[u/schaden81]

The positive post is slightly larger than the negative post. This means the positive terminal will easily go onto the negative post, but not vice versa. Judging by how tight the sensor wire already is, it looks like you have the battery oriented wrong and may be in for a nasty surprise if you get the second post connected. Please double check that you have the battery placed the right away around before proceeding. The new battery is identical to the old one, and post sizes are pre determined, so the terminal should fit correctly without much effort.

[u/Lopsided-Poem5936]

If it's really bad you could buy a new one but I'd just undo that nut so it's real loose then pry that sucker open a bit to fit.

[u/Semecumin → u/Lopsided-Poem5936]

Seems you’re the only one that read the issue.

[u/ReasonNo9316]

Doesn't anyone clean their posts before installing a new battery?

[u/tomhalejr]

You see how the old one has those diagonal slash marks in the posts? When those terminals are tight, they dig into the tapered post,, so the terminals set tight. 

You have to back the nut off more to get the terminal to spread as you are twisting it down onto the post. Do not hammer it! You can use a flat head between the ears of the terminal to try and get a little more seperation, but the cradle nut of the terminal bolt has to come up into the terminal end to tighten the ears down. 

Even if you had a terminal spreader, if you remove the nut and bolt and spread the terminal too far, it won't tighten back up. 

[u/Odd-Concept-6505]

You said you can't expand the old negative terminal BUT, if you reamed it wider so it goes on just barely loose could you then tighten it? I couldn't see your tightening bolt underneath but I think I see the normal gap so likely yes. Since your terminal end is cruddy, that's what you want to shave "out/wider" and not shrink the new battery post.

reamer (not just a scraper=wire brush) with metal blades to ream terminal ends (female) like

https://www.amazon.com/khbyt-Battery-Practical-Scrapers-Protector/dp/B0HCXYW5F1/ref=mp_s_a_1_4

I have a different style but this sub disallows a camera jpg...

[u/AskAMechanic-ModTeam → u/[deleted]]

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[u/keep_username]

You have the two batteries back to back, if you turned them the same, the polarity looks the same. Cables should connect.

First step: make damn sure you aren’t hooking it up backwards! Next step, loosen the nut as much as possible and pry the u shaped thing under the nut upward, this should allow you to spread the ears open and gain clearance inside the terminal. Once it’s seated, you can tighten the nut and it should clamp. Repeat on the other terminal and you should have good power.

[u/Healthy_Log_6171]

Presildenting while black, mostly.

[u/BogusIsMyName]

I have a roll pin for this exact situation. I dont see anything significantly wrong with that terminal. I would not replace it. Just use my roll pin to open it up enough to fit.

But if your dead set against that, yeah you can replace that terminal. Probably going to have to order it so you may be stuck without your car for a day or so.

[u/Straight_Cucumber172]

battery is not backwards pay attention to the label placement. id probably get it replaced anyhow instead of stretching it. cause of how much corrosion is present

[u/Straight_Cucumber172 → u/Straight_Cucumber172]

please do not flip your battery around i see that the posted picture has the negative wire (black) over top on the negative terminal. OP has the correct battery placement

[u/DueLet1388]

Did you take the caps off?

[u/boostedride12]

Just turn the battery around. You have it 180 out in the first picture. The new battery doesn’t have a slighter bigger negative. There designed so you can’t switch the terminals around and cause damage

[u/Straight_Cucumber172 → u/boostedride12]

look at the label placement id say OP has their battery in the correct way in my opinion

[u/Coyote-Morado]

Sounds like you are trying to hook your battery up backwards.

[u/Straight_Cucumber172 → u/Coyote-Morado]

look at the label looks correct to me

[u/LakeMichiganMan]

My Accord calls for a Right. But all they had in stock was a Left in that size battery. Next. Your battery cables and wires are not rusty so not red. Your battery posts are lead. Coppers corrosion is greenish. Aluminum's corrosion is white and powdery.

Now spread that battery connection apart so it fits over. Take off the Red and Black plastic protection covers on the post first.

[u/bat_rastards]

You just need a Battery Clamp Spreader tool. Once you beg/borrow/buy this tool, loosen the bolt on the clamp and spread the jaws with this tool.

[u/amanindandism]

The terminal looks fine to me, just get the clamping nut nice and loos and use a flathead screwdriver or something similar to spread the terminal a bit. The terminals are tapered so you want to get them on as far as possible before tightening them for best fitment. Any corrosion can be rinsed away with plain water.

Also make sure the protective caps are removed from the terminals. It sounds obvious but I've seen it happen.

[u/rareman1965]

There the same just turn the old one around

[u/Internet_Jaded]

Did you remove the plastic cover from terminal?

[u/Pauly4655]

I think it’s just you mate

[u/John_Human342]

Its won't fit because its the wrong terminal. Spin the battery 180°

[u/Professional-Race460]

Stop what you're doing you need to take the battery back because you have a diesel Civic not a regular Civic they require different cold cranking apps and all kinds of fun stuff

[u/Astroboy-478]

Maybe try replacing those cables and battery terminals 🤷‍♂️🤷‍♂️ I’ve done it a bunch of times, using larger then stock gauge welding cable and crimped on or soldered ends with water resistant heat shrink on the the ends as well.