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2007 R12R - Corrosion under the gas cap

fletchdude

New member
I had to remove some screws and the tank fuel ring in order to mount the Bags Connection EVO tankbag hardware. I encountered some corrosion to the screws and some surface rust in the basin where the fuel cap mechanism resides. I removed the red assembly and cleaned with a rag but wonder if I should clean with some sort of corrosion preventative. I also wonder if this is normal. Petrol being what it is I assume corrosion could occur where we put gas in, over filling etc, but is there something else that needs attention?

Fletch
 
What's the best way to treat the corrosion thats already formed? I was going to clean up the threads with a tap and some oil. It's the rust in the cap basin that has formed. I'll see if I can send a picture off my phone.
 
Jim - there is plenty of info in the thread in the R1200R specific forum on r1150r.net as to how people "fixed" that. I think it happens to bikes that don't have tank bags and are ridden/stored in the rain, or ones that are washed too frequently. Hmmmm... I seem to recall you doing both, so...

Seal it up and use the rubber ring. End of problem.

BTW - also see this thread - http://www.r1150r.org/board/viewtopic.php?f=20&t=22416 LOTS of info/pics/ideas/etc.
 
I read the link and all I can say is, wow. My bike is literally spotless except for this and it would have gone uncovered if I hadn't tried to fit the tank bag locking ring. I will employ what I learned from the thread. Lots of good advice there indeed. I will make a trip to flight test this morning and see if the mechanics have any chemicals and supplies for the repair.

I do have a related problem now. I wasn't lucky enough to get all the frozen screws out and have one broken stud. I was going to drill it out and re-tap the threads. Sound OK?

Fletch
 
I do have a related problem now. I wasn't lucky enough to get all the frozen screws out and have one broken stud. I was going to drill it out and re-tap the threads. Sound OK?

Fletch
"Kroil" + time, and then put two nuts on it, lock them together and try to back it out. Drilling it out and retapping might well result in a hole into the tank. That's a blind threaded recess into the tank, with not a lot of wall thickness. Plus keeping drilling chips out of the fuel tank might be a bit of a challenge.
 
"Kroil" + time, and then put two nuts on it, lock them together and try to back it out. Drilling it out and retapping might well result in a hole into the tank. That's a blind threaded recess into the tank, with not a lot of wall thickness. Plus keeping drilling chips out of the fuel tank might be a bit of a challenge.

Unfortunately the stud sheared off flush. Nothing to grab. It's one of the four that hold the hinged cap in place. Maybe I can just get by with the other 3. I really hate to leave it in there. The only other course would be "Kroil" and an easy out.
 
If you cannot fit two nuts on it, then you may be able to get a good hold with a vise-grip.... after much soaking with a penetrating oil. While applying direct heat with a torch is not a good idea, letting it sit in the sun or using a hair dryer may help.
 
Unfortunately the stud sheared off flush. Nothing to grab. It's one of the four that hold the hinged cap in place. Maybe I can just get by with the other 3. I really hate to leave it in there. The only other course would be "Kroil" and an easy out.

Impatience will do that.. :banghead (I assume it's the one that was sticking up in your photo.)

Dunno what to suggest. Drilling it with a hand drill is a quick path to disaster IMHO, and trying to fit it on a drill press, well, you'll need a very big drill press (one that has a floor stand and a deep "throat") to clear the tank. I've had amazingly bad success trying to drill out small screws like this, especially with a hand held electric drill. Invariably the drill but will wander (since it's usually impossible to centerpunch the busted off screw, and the busted off surface is never smooth and flat) off the screw and start chewing up the surrounding metal. I think I have a 100% record on that.

A really good shop may be able to handle it. Besides the deep throat drill press - they'd need a drill bit that is just the OD of the screw at the bottom of the thread valley, and preferably - a very short drill bit that won't wander around. You then need to know the depth of the threaded insert (you can measure the depth on one that isn't broken) and make sure the drill bit doesn't go quite that far.

I avoid EZOuts - I have a great record of breaking them off in the threaded bit I'm trying to extract, and they are absolutely impossible to drill out since they're about as hard as the drill bit.

Did a Google - turned up: http://www.zorotools.com/g/Drill Extractor Tools/00065861/

Looks like a good solution and not horribly expensive. You probably do have to make certain the size of the tool is correct for the broken off screw size.. and there is a vague possibility you might be able to use this in a hand-held drill.. mebbe.
 
Don,

Impatience and ignorance has been my nemisis on this process, thanks for saving me from further disaster. I wish I had posted sooner (all i wanted to do was mount a stupid tankbag, sheesh). I think at this point I will clean up the rust, buy the gasket and get by with the other screws for now. I'm lucky to have several shops and skilled technicians and engineers I can lean on. I'm thinking I'll drain the gas and pull the tank this winter and do this on one of our big drill presses and use the extractor you posted. I'm going to go talk to some environmental technicians and aircraft mechanics to see who gets to do this.

Fletch
 
Crap. Now I've got to go pull the ring on both my GS and wife's R to check it. Thanks for nothing, guys... :banghead LOL
 
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