Alternator Water Proof????
Just recently had my alternator boosted. The mechanic who did it said that if I submerge my alternator in mud or water that it will mess it up.... Truthful???? I am not sure but it doesn't make sense cause how do the guys with snorkels keep there alternator from dieing. Just wanting to know because i am debating on making or ordering a snorkel.
No real way to do it - it needs airflow to breathe.
The two common problems that alternators have with wet are both mechanical:
1) Exposure to mud usually grits up the brushes and brush holder in the back of the thing, and the brushes "freeze" out of contact with the slip rings. Flush with contact cleaner (preferred to remove the rear case first - that lets you relube the rear bearing as well) and dislodge the brushes.
2) Repeated exposure to water can cause rust on the springs behind the brushes, which weakens them and the brushes can no longer maintain contact with the slip rings. Replace the springs (may as well just replace the brush holder assembly in toto - it's usually easier to find anyhow.)
The only difference between an "automotive" alternator and a "marine" unit is that the marine unit will have spark arrestor springs in it. Why? Because marine engine bays do a much better job of collecting fuel vapours and catching fire (unprotected) than automotive engine bays do - so extra measures must be taken to prevent this from happening.
I talked with my alternator guy for about two hours about this one time, head-shedding, throwing out ideas, and shooting them down, and we decided that it's damned close to impossible to waterproof an alternator.
The second best solution would be to convert to a "high-mount" alternator, either by adapting it to the aircon compressor mount or by getting the 2.46L mount brackets (1995 and earlier, I think) - which typically can be bolted right up and made to work.
The two common problems that alternators have with wet are both mechanical:
1) Exposure to mud usually grits up the brushes and brush holder in the back of the thing, and the brushes "freeze" out of contact with the slip rings. Flush with contact cleaner (preferred to remove the rear case first - that lets you relube the rear bearing as well) and dislodge the brushes.
2) Repeated exposure to water can cause rust on the springs behind the brushes, which weakens them and the brushes can no longer maintain contact with the slip rings. Replace the springs (may as well just replace the brush holder assembly in toto - it's usually easier to find anyhow.)
The only difference between an "automotive" alternator and a "marine" unit is that the marine unit will have spark arrestor springs in it. Why? Because marine engine bays do a much better job of collecting fuel vapours and catching fire (unprotected) than automotive engine bays do - so extra measures must be taken to prevent this from happening.
I talked with my alternator guy for about two hours about this one time, head-shedding, throwing out ideas, and shooting them down, and we decided that it's damned close to impossible to waterproof an alternator.
The second best solution would be to convert to a "high-mount" alternator, either by adapting it to the aircon compressor mount or by getting the 2.46L mount brackets (1995 and earlier, I think) - which typically can be bolted right up and made to work.
i had to pull a XJ out of the trails cause the alternator failed on it due to mud/water damage. Once the guy got back to the parking lot, he took the alternator apart, cleaned it up and put it back on . Worked fine after that.
Your best bet would just avoid water/mud.
Your best bet would just avoid water/mud.
I'm flipping mine on top and locating two a/c compressors lower to maintain my air conditioner, power my on board air, and make it easier to replace the alternator/keep it dry for the simple fact that it is pretty much impossible to waterproof an alternator.
I'd like to see the bracket/setup for that dual compressor setup. Sounds interesting!!
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CF Veteran
Joined: Dec 2008
Posts: 1,533
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From: eaton ohio
Year: 93
Model: Cherokee
Engine: 4.0
it is very simple you just have to grind the bracket down there are pics in my jeep build thread. It bolts up the same and my jeep is a 2001 so it has a plug that goes in to the alternator. I took a plug off an older cherokee the style with the two 8mm bolts and spliced it in and it has worked perfect no problems
CF Veteran
Joined: Dec 2008
Posts: 1,533
Likes: 0
From: eaton ohio
Year: 93
Model: Cherokee
Engine: 4.0
it is very simple you just have to grind the bracket down there are pics in my jeep build thread. It bolts up the same and my jeep is a 2001 so it has a plug that goes in to the alternator. I took a plug off an older cherokee the style with the two 8mm bolts and spliced it in and it has worked perfect no problems
Junior Member
Joined: Jan 2009
Posts: 73
Likes: 0
From: Greenwood Arkansas
Year: 1999
Model: Cherokee
Engine: 4.0
mine is in the shop right now cause my Alt died this weekend when me n sum buds went muddin and I had to cross a deep water crossing "5" different times and went thru sum pretty deep mud holes
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