Gas Cap Problem! 280 SE Automatic 1970

[jrustad@aol.com]

Hi, Does anyone have a trick to getting the locking gas cap off of a 280 SE Automatic Mercedes - 1970?  I can lock and unlock it with ease, unfortunately, I can pull it off regardless of the direction I turn it.  I am new to the vehicle, is there some type of lock mechanism or other button I am supposed to push?  Or is there a trick to getting it to come off?

Unfortunately, I have no idea how much gas is in it so I am in a bind and don't want to run out! 

Any help you can give would be great!!!!

[scoot]

In the locked position, the Mercedes gas cap will turn freely.  In the unlocked position, the gas cap will not turn freely.  When it is unlocked it will behave like a "normal" Mercedes gas cap, which means you turn it counter-clockwise a little more than 90 degrees.  It doesn't just slide out like later car locking gas caps.    So when you can't turn the cap to the left easily with your hand, apply more force.  And verify that if you set the lock to the other direction the cap just spins freely when you turn it.

[mdsalemi]

Hi jrustad,

If the gasket on the gas cap is thick (like some aftermarket ones) or new, it might prove to be a bit of a chore to removed.
When locked of course you get the "spin freely action".
When unlocked, you might need to push very hard on the cap to compress the gasket, and you might need to use gloves to get a firm grip.
Once you get it off, you might consider putting a little grease (thin coat) on the gasket and on the metal end of the filler neck to ensure easier motion.

I hope that's your issue!

[Rolf-Dieter ✝︎]

Hi Jrustad,

I had the same problem as you describe in your thread when I picked my car up and the previous owner had to come out to help me out at the gas station. It is as Michael points out once it is unlocked the cap will no longer spin, you need to apply quite some down force (push hard down on the cap and turn) then turn it CCW to remove it. To lock it use the same method in reverce turning the cap CW. I felt quite embaressed to call out the pervious owner (a Funeral Director) to come out to help a retired Mechanical Engineer (yours truly) and my friend and Neighbour (a retired Fighter and Airline Pilot) to remove a simple gas cap LOL.

Once you done it a few times it will be fine.

Thanks Michael for mentioning the gasket, I'll check if I can get the stock gasket since it is a pain in the neck to unlock it and lock it again in the condition it is now.

[jrustad@aol.com]

You all rock!  Thanks!  It is counter intuitive to me - this make sense!

[KevinC]

Just checking...does anyone know of a good source for a replacement gasket?

[Rolf-Dieter ✝︎]

Hi Kevin,

Why not drop Tom a short note, he is most helpful. If he has them purchase 2 post one to me later I'll pay you for it of course (mine is for a 280 SL made in Dec. 1968, Tom has my VIN no on file).

Tom Hanson
Supervisor, Parts Operations
Mercedes-Benz Classic Center USA
MBUSA, LLC
9 Whatney
Irvine, CA 92618
949 598-4842 direct
949 598-4870 fax
Thomas.hanson@mbusa.com

[KevinC]

R_D,

I'll reach out to Tom. I have to order some additional items from him anyway. Was planning sometime in March. Didn't know MB would sell the gasket as a separate item.

Will let you know.

Kevin

[rb6667]

This may help.  I had the same problem except in reverse.  Scroll down to see the solution Achim came up with.  It worked for me.

http://www.sl113.org/forums/index.php?topic=16809

[Rolf-Dieter ✝︎]

Thanks rb6667  and Achim of course will check that out