How tight should car battery terminals be?

[vtecboy]

hello,

I cleaned my battery terminals today and i tight them very hard. i just want to know if they should be very tight?
the car is a 2000 mitsubishi eclipse, it have the terminals on the top of the battery.

 

[Drew99GT]

If you really crank them or the hold down clamp, you can distort the battery case to the point the seals on the terminals will leak.

So the answerer is not too tight. Just snug the bolts down until they're tight. You don't have to kill them like it's a lug nut.

 

[hemitom]

Tight enough so you can't twist them with your hand.

 

[Volvohead]

Originally Posted By: vtecboy
hello,

I cleaned my battery terminals today and i tight them very hard. i just want to know if they should be very tight?
the car is a 2000 mitsubishi eclipse, it have the terminals on the top of the battery.


You're talking about a couple Nm max in most instances.

Just enough to make a solid electrical contact and keep the terminal firmly attached.

Much more than that, and you start distorting clamps and posts.

Wipe a little film of vaseline on the posts first, and you should prevent most moisture and terminal corrosion issues.

 

[Oil Changer]

Physically tight does not mean electrically tight. Having them loose enough to turn by hand is fine if they are kept clean. Kept many cars like that w/o issue. It can even come in handy.

 

[mechtech2]

If you didn't break anything or distort parts, you are OK.
Most important is the shiny cleanliness of the mating surfaces, then good and snug afterwards.

 

[The motor guy]

As tight as they were when you took them off. Actually a little bit less since they get stuck on there from corrosion.

 

[Bgallagher]

Break out the air gun like the dealers use on oil drain plugs haha.

Dont go crazy. Put some vaseline on the terminals and tighten it so there is no movement. No need to he-man it

 

[JHZR2]

Just tight enough. Get them down hard on the terminals, but be careful - cables and case can be broken.

 

[Donald]

How did you clean the terminal? A wire brush type of thing, or a scraper for the terminal and clamp? The scraper makes one smaller and the other larger, so you need to compensate by tightening (a little).

I agree just a tad more than hand tight.

But I cannot believe you can cause a leak by over tightening a clamp. Mounting clamp yes.

One thing I could see causing a problem would be to rip off a super tight clamp rather than using a puller.

 

[Mr Nice]

Snug.

 

[tinmanSC]

The clamp nut on most cars should be tightened to about 140-180 inch pounds, or about 11-15 foot lbs. I've read this a few places, it's some where in the Lexus service manual for my car, or maybe it was a TSB. I also heard from a guy who works in electronics, specifically for vehicles, that 13 foot lbs is the normal tightness, which is right in the middle. He specifically mentioned 13, you know, a nice round number to remember.

 

[GearheadTool]

Go as tight as that you are comfortable that they won't move at all!

 

[Chris Meutsch]

Originally Posted By: hemitom
Tight enough so you can't twist them with your hand.


This. And grease the posts/clamps up real good before.

 

[SatinSilver]

Not Gorilla tight.

 

[antiqueshell]

Originally Posted By: Chris Meutsch
Originally Posted By: hemitom
Tight enough so you can't twist them with your hand.


This. And grease the posts/clamps up real good before.


Exactly.

The lugs SHOULD NOT move with light pressure on them from your hand.

 

[Tegger]

Originally Posted By: vtecboy
hello,

I cleaned my battery terminals today and i tight them very hard.

Congratulations. You just broke your battery. Watch for that wonderful fuzzy green corrosion, showing up real soon!

How tight should the terminals be? Use a SHORT wrench and use your PINKY finger ONLY to turn it. If your pinky starts to hurt, stop turning. That's it. Stop. No more. Don't add "just a bit more torque". Stop.

But it's too late for you.

 

[KrisZ]

Isn't it great to ask for advice AFTER you did the job?

 

[Volvohead]

Originally Posted By: Tegger


But it's too late for you.



Ouch.

What's done is done.

To the OP, the job is already done. Can't undo it. Don't look back on it. Otherwise, it will drive you insane. It's probably going to be fine. If not, deal with it then.

Learn and move forward.

If I had a nickel every time I learned something the hard way . . . I'd have a lot of nickels.

Here's a tip from an old guy (me): sometimes it still breaks even if you did it right.

 

[mechtech2]

Do not grease them before - that is silly. Grease them afterwards.
Why introduce an insulator into an electrical connection?
Just because the car may still run is not a reason to use inferior procedure.