Ruined gas tank?

[JESRR]

I haven't posted here in quite a while, but you were all a lot of help when i did so maybe you can help me again.

I changed the fuel filter on my '02 with no problems at all untill I tightened the nuts back up. I didn't think I was using much torque, but I must have been because I snapped one of the threaded studs off. I was pissed to say the least.

Are there any other ham fisted fools out there who made the same mistake and found a solution other than buying a new tank? I'll be calling the dealer today, but I assume they'll tell me to buy a new one so my second step will be talking to an experienced welder.

I have fun doing my own work, but I guess this is the price I pay

John

[Capt. Blackadder]

I remember reading about a similar incident over on ADVRider. The guy was able to locate an experienced welder who brazed the threaded stud back on. Good luck!

[taosports]

If it makes you feel any better John, I did something similar. Those nuts just need to make the o-ring snug between the cover and the tank, but the tendency is to over torque it out of fear that the seal will not be good enough. Anyway, what I did was strip one of those studs but only near the base, so I was able to use a nut as a spacer and have some threads at the top that gripped the 2nd nut.

In your situation, how about just drilling another hole and putting a bolt through it? Think that would be the cheapest solution. Welding I guess could be another alternative but you certainly don't need another tank!

Let us know how it all works out.

[taosports]

Here's the link Capt. Blackadder is probably referring to :

http://www.advrider.com/forums/showthre ... =tank+weld

[yjleesvrr]

There is an amazing amount of fragile parts on a bike that is otherwise so durable.

[JESRR]

The Internet is a truly awesome resource.

Thanks for the tips and link gents, I'll let you all know how it goes.

John

[Capt. Blackadder]

Here's the link Capt. Blackadder is probably referring to :

http://www.advrider.com/forums/showthre ... =tank+weld

That's the one. Good work, Michael.

[Ric]

Never owned a BMW....sure am itching to get a 2007 R1200R.
I've owned about 25 other jap bikes though, and have restored numerous vintage machines. Do all my own work from engine rebuilds to painting.

So let me get this straight....BMW doesn't use a small petcock type fitting for attaching fuel line to the tank ? And on top of that, some BMW Engineering genius designs the fuel filters to go inside the tank !!!

Is this correct ? Or have I just had a Mechanical Engineers silly nightmare ?

[socalrob]

Ric posted:
So let me get this straight....BMW doesn't use a small petcock type fitting for attaching fuel line to the tank ? And on top of that, some BMW Engineering genius designs the fuel filters to go inside the tank !!!

Ah, the benefits of adding about a million times the complexity so that we can have a pressurized fuel injection system.

Have you heard how there is no cross over in the tank & no petcock on the other (reserve) side so that a good portion of the tank capacity is not used?

Another brilliant design feature.

Oh wait, there's more, the plastic fuel line quick disconnects that burst if looked at wrong (might want to carry a spare & spare O rings).

Surely that is all. Wait, there is still more.

Funky little steel clips that you crimp onto those high pressure fuel line connections, they seem to sometimes come loose. BMW doesn't need any real screw types, no siree!

Disclaimer: I have never had any of these problems and they may or may not be mythical internet ghosts in the machine.

Regarding welding on the tank, I had a Hodaka gas tank (one of those cool all chrome jobs) brased for a stress fracture. The welder filled the tank with water prior to welding on it. Pretty smart I thought. Never had a problem.

[Ric]

Ric posted:
So let me get this straight....BMW doesn't use a small petcock type fitting for attaching fuel line to the tank ? And on top of that, some BMW Engineering genius designs the fuel filters to go inside the tank !!!

Ah, the benefits of adding about a million times the complexity so that we can have a pressurized fuel injection system.

Pfffttt....!!!

Could I get an 07 R1200R, rip out all the FI and electronic cr*p and replace with two nice flat slid carbs and maybe a CDI iggy ?

Then I could install a proper petcock and inline fuel filters like God intended bikes to have !

[RideandDrive]

Manual says torque on fuel tank stud nuts is 6 NM. Not much..

[CycleRob]

That GS rider says his tank studs broke upon loosening them because of rusted, frozen threads. Those threads don't usually rust, but riding on salted icy roads, like some GS riders will do, may have caused the accelerated corrosion. In those and other elective surgery risky looking cases, like the rusted toe-in adjuster threads on my `98 truck, I sprayed them with Liquid Wrench or Knock-r-Loose a week before it went in for it's frontend adjustment. Exhaust manifold stud threads are another sure trouble spot if not pretreated with a nut-buster liquid.

A lot can be learned by other people's mistakes. I am going to check and if necessary remove the nuts 1-at-a-time to grease my tank studs at the next service. Be aware that greased threads totally screw up the specified torque setting. Put the torquewrench away. You CANNOT use the same torque on greased or anti-seize treaded threads because the friction in the threads, the torque determining factor, is greatly reduced and you will SNAP the male part off. Ouch.

On all low torque nuts-n-bolts I use my cerebrally calibrated, experienced right hand. In the case of the fuelpump plate attachment to the fueltank, you'll first notice how tight they were, or were NOT, when you took them off. Then, on reinstallation, criss-cross the tightening sequence with a screwdriver type nutdriver socket and stop tightening BEFORE the flat fuelpump plate starts to distort at the studs. If your gasket is still soft, the nuts will tighten all at once as the metal parts bottom out.

When I warn newbees against doing certain service operations it is with the memory and knowledge of how easily these types of disasters can occur. This stud snap on removal disaster is a new one on my radar and will be added to the list.

[jbuzbee]

Could I get an 07 R1200R, rip out all the FI and electronic cr*p and replace with two nice flat slid carbs and maybe a CDI iggy ?

You sure can:

[socalrob]

That looks like a oilhead (1150 motor) S bike to me, not a hexhead (1200 motor), still, a nice looking bike.

Randy (Rchop) built a custom chopper with an R1150 motor, using carbs, & he was very happy with the performance.

[acejones]

Ric,

I don't think you can use a petcock on FI systems. Also, most cars today with FI have the fuel pump/filter inside the tank. It all has to do with pressuring the FI system.