Broken Fuel Tank Mounting Studs

[ddodson1]

I just dropped the fuel tank out of my 1965 230 SL to have it refurbished.  Despite lots of penetrating oil, two if the mounting studs broke off during removal.  Any suggestions for replacing the studs or other ways of securing the tank on reinstallation?

[merrill]

I too broke a mounging stud when working on the fuel tank for my 66 230.
I broke the stud in the center of the car near the compensating spring.

I ended up grinding off the remaining metal, drilling and tapping the hole for a bolt.  installed the tank and ran the bolt in the newly tapped hole.

worked just fine, much easier than trying to re create the welded in stud .

matt

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

[ddodson1]

I was thinking along those lines.  When you drilled out the stud were you able to use the original female threads or did you have to tap it out to a bigger size bolt with a tapping tool?

[merrill]

I do not remember the exact tap size,  I think the replacement bolt was about the same size as the stud that broke off.



Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

[seattle_Jerry]

Now I don't feel so bad. I'm in the middle of the same project. I will take and post pics.

8mm tap, 17/64 drill bit

I am drilling a hole, tapping it, threading in an 8mm stud and if there is enough room behind the plate, backing it up with a nut and loctite. If not, just loctite. My only concern is that there won't be enough threads to reliably hold the stud without a nut on the back side.
The other option is to put some jb-weld behind the plate and screw the stud into the plate and jb-weld.

1967 230SL Havana Brown Auto with A/C

[ddodson1]

Success!  I cut off the broken studs and drilled them out.  Then tapped new 8mm x 1.25 threads.  Worked like a dream.

Renu'd tank is in and she fired right up on clean fuel for the first time in 20+ years.


Thanks,
Drake

'65 230 SL - Silver