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Wichita
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OCT 21, 05:54 PM
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I had an aluminum battery tray that was screwed into the body panels (inherited it). I don't think it was an original battery tray.
It's in really good shape, but noticed when I removed it that there was galvanic corrosion from the fasteners and body panels, causing some eat through holes.
I haven't decided yet to put the battery tray back, as I may relocate the battery and use something else as a tray, but curious to know which steel screw fasteners to use and which to avoid to prevent dissimilar metal corrosion but also avoid the screws from rusting on their own too.
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theogre
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OCT 21, 08:09 PM
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Sorry but almost no type of steel stops that.
More so in Al battery trays and related when battery leak the tiniest bit.
You could try sealers or grease that keep "water" away but they have "lifetime" limits....
sealers including "under coating" can crack over time and just 1 expose the base metal is enough to rot and worse many sealers will hold "water" and rot faster.
most grease runs and/or washes out often in a very short term. Many greases can wash off very easy because not made to be weather resistance or resistance just from mild soaps but even Permatex Brake Grease can wash out if hit w/ pressure washer etc to wash a car.
Example: I use PBG for helping grounds bolted/screwed to engine and frame but even w/o direct attack from road crap you still need to check them every year to a few years in places w/o road salt problems. While last a long time here doing that, any time a connection is a apart then will often need re-greased. I'll be re-greasing many grounds in the engine bay when done fixing other problems.
Related: see http://www.fiero.nl/forum/Forum2/HTML/146198.html where Al Heater Pipe rotted where plastic coat worn thru where steels brackets touches.
Besides fixing the leak, I used some sheet polypropylene as buffer any place the pipe can touch steel.
Better off replacing w/ steel battery tray. If is bolted/screwed down, maybe get steel w/ powder coat not paint.
But either finish can/will fail if the base metal is exposed having same problem as sealers said above.
So avoid drilling extra holes etc.------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave
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