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Discussion Starter #1 (Edited)
Hi guys. My 2007 X5 4.8i is our winter vehicle. So I am fixing it these days. I got an oil leak through oil thermostat gasket, so I am trying to change it. The procedure requires removing the alternator. Upon removal of all things like braces, wires, bolts etc. I have the alternator ready to go. But it won't... :mad: It moved about 12 mm (looking at the Top bolt hole I can see most of it). But it took too much effort and a pry bar to get there. I never heard anyone on Youtube mentioning this problem (hard to remove / install alternator once it is unbolted). Does anyone know?
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 98K miles NOKIAN WR G3 12K miles
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Discussion Starter #3
Thank you Doug. I haven't removed the passive tensioner, nor the refrigerant line holder yet. The thing is that the alternator doesn't drop off. Not that I don't have any room to pull it out, but it is just like stuck on the engine.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 98K miles NOKIAN WR G3 12K miles
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Did ya whack it gently - apply mechanical hysteresis - to break corrosion alternator frame to engine block?
 

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Discussion Starter #5 (Edited)
Yes I did wack it with a 16 oz. hammer through a 2 x 2 piece of wood. I don't see any corrosion marks on the engine though. Of course the corrosion may be on the alternator mounting fork itself.
 

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Discussion Starter #7
I am a bit scared, but of course have considered that. Have you had this problem and applied this solution?
 

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02/2012 X5 35d M57Y CPO 98K miles NOKIAN WR G3 12K miles
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Only when I was sure that that was the only impediment to the piece coming loose.

More gentle that a whack is an overnight soak in Coca-Cola dilute phosphoric acid (Coca-Cola Merchandise No. 4) solution - 2 pH. Soak a rag in coke and wrap it where it will do the most good.
 

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Discussion Starter #10
Thanks, Doug. I don't think it is possible to wrap a soaked rag, but I will try. I believe that vinegar has the same acidity as Coca Cola, so I may as well use it?
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 98K miles NOKIAN WR G3 12K miles
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Thanks, Doug. I don't think it is possible to wrap a soaked rag, but I will try. I believe that vinegar has the same acidity as Coca Cola, so I may as well use it?
Absolutely. 1 M acetic acid is 2.4 pH. 1 M is about the concentration of household vinegar.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 98K miles NOKIAN WR G3 12K miles
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I don***8217;t see any corrosion. It looks to me like it***8217;s cocked on the very tight parallel surfaces. I think judicious tapping and wriggling to get the alternator square on the mounting surfaces and it ought***8217;a slide off.
 

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It looks to me like it's cocked on the very tight parallel surfaces.
+1, needs to get off evenly

I filed mine a bit before putting it back so it was easier. Otherwise it is even harder to put back than removing since there is no leverage point.
 

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Discussion Starter #18
Thank you guys all. I really liked all the suggestions, and I think Doug ruled out the corrosion issue. I also like the Pelican suggestion where to put the pry bar to move the thing. If I can move it up than I can tap it down later, and so on. I really don't like the bushing on the back side of the alternator fork
 

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Discussion Starter #20
Okay then. You guys have been a great help for me. Maybe you can suggest something on the following?

1. This infamous oil thermostat gasket. Should I use a Permatex oil-resistant silicone on a new gasket to have it done once and for all?
2. I am an engineer, but not electrical. When I get the alternator out, what is the best way to clean it without disassembly not worrying about its gut contamination?
 
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