2018 Infiniti QX60. I replaced the battery. I used felt washers and dielectric grease and I thought I thought I made it nice and tight and did everything right. I had some starting issues, so I made it even tighter and it was okay for a few months. Now I am seeing lots of corrosion around both terminals. Starting feels weak. Defroster fan speed dips when I turn the steering wheel. I am afraid of breaking something if I make those terminals tighter. Is there another possible cause or just a bad battery install?
tightening cables is not a good solution to regaining a good connection. When the cable ends are snug enough that they won’t slip when you attemp to twist them with your bare hand they need no more tightening, the connections need cleaning or replacing.
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That makes sense. I’ll try cleaning everything up real well and reinstall.
I’ve known those who have replaced good batteries thinking that was the problem, when in fact the battery current sensor was actually the problem.
https://www.autonationparts.com/search?search_str=battery+current+sensor
Tester
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Can you post a picture, please?
Are the cable ends replaceable . . . bolt-on, for example?
If they’re bolt-on, I’d just replace the cable-ends, if it were me
in my experience, those felt washers and dielectric grease don’t actually prevent corrosion
All they do is lighten your wallet, imo
Good ideas above. The alternator could be involved also. Caution: I’m just a simple-minded diyer , a total pinhead, a know nothing, so be sure to take that into account. I couldn’t possibly be right. Correct?
I have seen the felt washers not allow the cable ends to go far enough down on the battery post(s) for them to properly tighten up…
I always throw (or hand them back) away so the terminals will bottom out on the battery post…
I always use a thin film of dielectric grease on the battery post, install battery terminals on battery post making sure they are tight enough that I can not twist them by hand, then put another thin film of dielectric grease over the terminal ends/battery post and I have never had battery corrosion on any of my vehicles…
Those felt washers can prevent the clamp from going down on the post all the way, the result is a clamp that won’t clamp down on the post. The post is tapered, the clamp needs to be down as low as possible.
A new battery shouldn’t leak acid, did you damage the terminals while over-tightening the clamps?
The battery posts have a seal around them where they enter the battery. This keeps battery acid vapor in and external elements out.
When tightening the battery clamp bolts, over-tightening can impose a bending pressure on the terminal and lead to a slightly damaged seal. Once that happens, battery acid vapors can seep up through the seal and lead to ongoing corrosion.
Or they should. Clean the area and put silicone around there to make sure they are sealed.
If you put silicone/rtv around the base of the battery post to keep it from leaking, then you will be doing what Nevada and I JUST got through saying, it will keep the terminals from going all the way down and properly tightening…
Looks like nothing was properly cleaned when the battery was replaced, including the hold-down bracket.
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Blech. I can see the voltage drop across those cable connections from here.
Those cable ends look to be bolt-on and replaceable
Do it and report back, please
How does that positive terminal come apart for cleaning? Should I pull both those nuts on top in addition to the one where it attaches to the post?
I would loosen the nut on the left side and see if the clamp comes off. The I’d clean the clamp and post with a wire brush.
I’ve never had to take that configuration completely apart to get a low resistance connection. I’ve always been able to achieve success by cleaning the oxidation & gunk from the post and the inside of the connector using an inexpensive battery post cleaning tool. But I’m just a knucklehead diyer and it might take more than that in some cases. I have needed to completely replace the cable on one of my vehicles b/c the corrosion damage was preventing me from getting a reasonably tight clamp on the post. to minimize the chances of short circuits, I always disconnect the negative before doing any work on the positive.
Remove the cable nuts, remove the clamps from the battery and place them in a dish of very hot water: 150 F. The acid and corrosion will drop off without scrubbing. All the green corrosion in the middle of the clamp must be removed as to not contaminate the new battery.
Replacement battery clamps are inexpensive, see your Nissan/Infiniti dealer:
Before and after cleaning:
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