Maxine the 318 - Rust Treatment July 22 2013

Maxine's battery had issues holding charge, and the culprit was a battery that had started to leak battery acid. 

Battery inside battery compartment.

After removing the battery and the battery tray, it didn't look good. There had obviously been a long history of leaky batteries.

Rusty battery compartment.

This could not stand. To battle this rust, I employed POR15. I bought the starter kit that is about the perfect size for a small project this size. This is the kit that we bought.*

POR-15 starter kit contents.

The first step was to remove the rust. A drill with a steel wire wheel on the end of it made quick work of the rust. I wore a respirator, since rust powder was going everywhere. I used a vacuum to remove all the loose rust after I was done.

Battery compartment with a drill with a wire wheel attachment.

The next step was to degrease the area. The kit included a bottle of Marine Clean for this purpose. I wiped Marine Clean all over the surfaces and then wiped up the excess with a dry paper towel.

Paper towel wiping up excess Marine Clean from the battery compartment.

Applying Prep and Ready was the next step. This prepared the metal for the POR15 to bite into. The directions said to keep brushing it on so that all metal surfaces are wet for at least 30 minutes. I did this for an hour, reapplying about every 5 minutes or so.

Prep and ready poured into a clear cup with a brush inside the cup.

After an hour, the battery compartment took on a grey, hazy color where the exposed metal was. 

Battery compartment with formerly rusted surfaces now appearing dull and grey.

We were now ready for POR15. I brushed on two coats, waiting several hours between coats. POR15 is fairly thin, so it brushes on easily and flows into all the cracks and the crevices.  

Battery compartment with black POR-15 painted on it.

I could have just left this as it was, but I thought it would look better in red. Yes, I realized that this area is going to be unseen after it is covered up by the battery tray, but if anything is worth doing, it is worth doing right. Rustoleum makes a color called Sunrise Red that is very close to BMW's Brillantrot, which makes things very convenient. Three thin coats did the trick.

Battery compartment with areas masked off and a can of Rustoleum sunrise red in the foreground.

With the paint dry, it was time to put everything back together.

Battery compartment after spray painting red.

I re-installed the somewhat used battery mat, which serves as the first line of defense against battery acid by absorbing and neutralizing the acid. The battery I used was a Odyssey PC680, which is much lighter than the unit it replaces and still has enough cranking power to start the car. I'll have to make a proper battery tie down, but the stiffness of the battery cables and the lightness of the battery makes it almost unnecessary for street driving, but obviously track driving would require one. The battery tie down will have to be a custom job, but that is for another post.

Battery compartment with new small battery hooked up.

POR15 is pretty easy to use, and the starter kit makes it easy, since they give you everything that you need. The battery compartment looks much better, and is now protected from future rust. As a bonus, we ditched a few pounds from the car by switching to a lightweight battery.

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