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Old 09-27-2012, 03:23 PM
QuickSilver2 QuickSilver2 is offline
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Location: Pasadena, Ca
Join Date: Sep 2012
Posts: 5
Mein Auto: E38
Alternator/Oil Fire

This post is three parts.

Safety Warning:
Eventhough I should know better, I broke one of my standing rules of always working on cars when the car has sat for a while and the engine compartment has cooled down.

Always have a fire extinguisher in the working area.

I had a fire extinguisher as well as a garden hose nearby.

I was changing the oil in my car and I mistakenly spilt some oil from the filter canister onto the oil line which of course trickled down to the alternator. This was not a few drops but quite a dribble. I didn't think much of it then but what I should have done was to degrease the whole area to get any trace of oil away from the alternator.

After I replaced the filter and poured fresh oil into the crankcase, I started the engine for a minute to buil dup the pressure and shut it off.

When I went back to the engine bay I noticed that there was a fire right at the alternator.

I applied the fire extinguisher but it was not going out (will follow up with a proper garage fire extinguisher for all fire types) so I knew it must be an electrical fire so I raced to the trunk and unhooked the negative cable from the battery.

After everything cooled down the damage was this:

I have since replaced the oil line but I opted not to install the cable that goes to the positive terminal on the drivers side cylinder head.

Root cause:
So Guys, what happened?

1) How could the two items have been able to touch each other?
2) Was the fire caused by the touch above or just from oil inside the alternator?

Thanks. I know it's a little winded post but I wanted to give as much data so that I can get good educated responses.
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