Need Help - Protecting Alternator/Car Battery From mud/water

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Dane_Bowers

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Hi, so I have a 15 year old truck with 154,000 miles on it and a 15 year old alternator. I have been going mudding a lot recently. One day after mudding, my truck said my battery wasn’t charging, and my truck died shortly after. I put a new battery in and it started right up... until it died 2 days later. I got it to the mechanic and he said the alternator had died. My engine bay was absolutely caked in mud, including the alternator and battery. So how do people go mudding/water fording protect their alternators and car batteries? Thanks
 

Bama_Kiwi

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Water ingress will kill an alternator deader than fried chicken.

There are sealed (water proof) aftermarket alternators you can buy, but I imagine these aren't cheap.

I also seem to recall alternator relocation kits (essentially raising it up in the engine bay and changing the routing of serpentine belts) being a thing.

Otherwise, maybe you could fabricate some sort of shield or splash guard.

But, failing all that, just do your best to not get your alternator wet.
 

smritte

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Personally, I don't worry about it. The only issue I've seen is mud on the brushes. Once everything dries off, they normally start working again. The one's I use to see fail after a good mud romp were normally high mileage. When I tore them down I would see what looked like something damaged the brushes, possibly small rocks. As for water, if it was going to be an issue, you couldn't drive it when it rains. Most of my vehicles the alternator was mounted low. I've had no issue sitting in water with the engine running (alternator and starter submerged) while trying to extract someone. Worst case was the alternator stopped charging until the brushes dried. I commonly drive through deep water crossings on my mountain trips without issue.
 

MidOH

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Water is fine, mud is a bit much. Long distance overlanders shy away from mud for a reason.

We ran a huge heavy rubber flap on our front bumper that mud would push under the truck like a giant front skidplate ski.

Wash the battery off every single night. Not spotless, Make sure around the posts are perfecly clean, and no dirt between + and -. Dirt drains batteries. Popping the hood should be part of your ''pulling into camp'' routine. Clean battery, check air filter, fluids, every time I get 5 minutes to myself in camp.

Alternator likely needed rebuilt anyways. Carry a spare. You can make a splash guard for the alt, but do not seal it up. Likely time for a starter as well. My alt is up high, so I don't worry much.
 
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USStrongman

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YOunger guys here like to go mudding and then leave their rigs caked with mud as a sign of pride. "Oooo, look at me!" kinda stuff.

Be diligent and increase the life of your truck and its systems: Wash it. Everything. An engine bay full of mud will cause excess running temps as there is reduced airflow, reducing the life if your rig.
 
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Pathfinder I

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I avoid mud when possible and I pressure wash the engine bay after every off road trip. My LGZ 3.6 V6 has been reported to have problems with mud causing Alt failure. If I was to have a problem I would build a shroud of some type.
 
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Outdoordog

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Not a bad idea to rinse the alternator after a good mudding.

I did some mud last year and my alternator was making whining noises. Had it swapped for a new one
 
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TXJeep

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Thats a prety old original alternator, so no harm in replacing it. That being said, it probably could have been rinsed and reused. I have been able to save several alternators by removing them and rinsing them real good.
 
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Pathfinder I

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Sorry to revive this old thread that I have already replied to. It's that time of year to have to deal with lots of nasty ass mud. I made a cover for my Alt using a corox bleach bottle. I cover the bottom half that gets hit with mud, covers the bottom half and the back, use a nytie to secure, remove when back home, concerned about extra heat.
 
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Showmemuny

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I have made covers for alternators on a few John Deere crawlers for mud, kind of like a heat shield that worked pretty good.
And I have seen debris shields for alternators on a few trash handler wheel loaders that could work for mud.
 

Shakes355

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Dirt and heat are primary alternator killers in my experience. Water is less of an issue. Contamination wears the hard-parts and heat kills the diodes. Older units are even less tolerant due to quality of design and materials.

Make sure any covers, bought or fabricated, provide ventilation as well as protection.

Edit: It dawned on me that Ford Escapes with the V6 have a clamshell that fastens to the alt from the factory to redirect and funnel airflow down to the unit. Should be ripe for picking at scrap yards and could potentially be used to fab up a more permanent solution for someone with the ambition.
 
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Boostpowered

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OK so I guess I'm the mud guy here. Others are correct water isn't really an issue mud can be but worse than mud or sand in an alternator is debris stick, leaves, grass.

Those of us who mud regularly find a marine alternator to replace the stock one and usually higher amperage. we relocate it to the top of the engine where there is much less chance of submersion.

Just riding through a puddle or a river crossing shouldn't have any ill effect on the alt unless something is already wrong with it or your vehicle is a know pos. Getting bogged in mud or sand is where stuff really happens usually when stuck and moving steering side to side it throw stuff up there.

There are also certain types of vehicles you shouldn't be mudding or even offroading in, to list those off would just start a fight though. An example however would be a ford explorer vs a k5 blazer one is built to move your soccer family the other was made to offroad, one blows transmissions like crazy the other blows mud off the tires when you hit the gas.

Think about what the original design intention of your vehicle is and don't deviate to far from that or else get used to breaking and fixing stuff regularly
 
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kunstmilch

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Reviving yet again...Apologies if this horse is long dead. As a driver of a 1999 GMC k2500 7.4 I also had to replace the Alt, went with I high output and outboard (remote) regulator. I spray Deoxit into the alternator and "flood" the inside with it to help clean it up and protect it, spray all the electric connections with it, then let it all dry up for a day. I also use NyoGel 760G like a dielectric grease only put extra around things like the spark plug caps. This grease seems to resolve the issue of wether or not to add too much grease to a connection as its a non issue. Then check the diffs and whatnot after as well, though I have a breather kit its always a good idea to check everything after being rough, you'd be surprised what you'll find, and its a lot less of a pain in the ass then being screwed at just the wrong time.