maxandtara

I plan to replace the all the allen bolts when I work on the oil cooler.

Do you think the replacing the shallow head allen bolts with regular height allen bolts would work?

Mister Bally

Use stock ones as you want to avoid galvanic corrosion from forming.

maxandtara

Mister Bally,

Would there be galvanic corrosion even if I use Audi OEM bolts?

One of the other bolts is a regular allen M10x40. I would just prefer to use regular height allen bolts to min. stripping in the future.

According to ETKA, the timing belt top idler pulley uses a 12 pt socket or a shallow allen so, I thought perhaps I can use 12point socket bolt for the oil cooler instead of the shallow allen.
I checked VW patheon (N10700001) 12 point socket is an alternative to N10468801.

I am concerned about the bolt underneath the exhaust stud. Would a regular size allen be bumping into pipe in front of that particular bolt?

The oil filter Housing/bracket is attached via 5 bolts
4 - M10x65 N10468801 (shallow/low socket allen)
1- M10x40 N9033160(3), 4 , 6 (regular height allen)

DA8

I’m not sure why you want to use different bolts. I changed out my oil pipe with the aluminum billet one a few years ago. Getting the cooler off is a feat. I hope I never touch it again. I had to use the double bolt trick on the manifold stud. It worked but it was tricky. I had to hand file the upper nut with my double nut so I could fit a socket over the top to reach the bottom nut. Allen bolts on the cooler itself are not the issue. Getting to them is the tough part. They are tight too. And be sure not to over tighten them or cross thread when putting back together. The engine block you are threading into is soft aluminum.

Mister Bally

By "stock" in my message, I meant OEM, in the exact size, material and coating. The proper OEM bolts are coated (blue-green) with a chemical that prevents problems with corrosion between the steel bolt and the two aluminum pieces it fastens.

maxandtara

Mr. Bally, DA8

Thanks for the advice. Trying to psych myself for the job by doing some research.

Right now I am adding about 8 ounces of coolant on a weekly basis.

Based on the posting I have read people have been stripping these bolts. I have seen people weld allen wrenches to get them out.

I think half the reason people strip these bolts is because of the shallow nature of the bolt.

On tough jobs bolts usually get rounded. I usually prefer install new bolts when I reinstall parts.

"Just in case" I have to come back I would rather deal with bolts that will be easier to remove.

DA8

I've stripped a few, I think one got stripped when I put the oil cooler back together. I could not tighten it, it just got to the point where it was sorta tight and kept spinning. So I put a bunch of red lock tight on it and put it in to the soft tight point. Anyway, I think there are 2 reasons they get stripped, 1 over tightening, and 2 is they get cross threaded when inserting due to strange angels and tough alignment of parts.

maxandtara

DA8

Again thank for the FYI, will be nice and easy with those bolts.

When did you do the oil cooler ? During a timing belt change or separately ?

Did you remove your engine support ?

I read one guy did it in a parking lot (He did remove the bumper).

DA8

I did it about 2 years ago. My signature pic shows the cooler dropped. I did remove the engine support. I did the timing belt the same time because it was close to do and all that stuff you only want to take off as few times as possible.