'39 Deluxe hinge boss repair (stripped threads)

[BillW810]

Another newbie question. The bosses where the hinge attaches to the hood are stripped. T-nuts were suggested as a repair. A couple of questions if you have done this.

How did you remove the stripped boss? It doesn't really look like a spot weld like for body panels. The 'spots' look too defined like they were drilled. See pics. I guess the backs are ground off, tedious.

Or cut The boss, grind flat weld T-nut to engine compartment side. No need to remove hinge 'plates'. I had to remove 1 side to straighten the plate.

Pic 1 is "engine comp", pic 2 is "hood side"

 

[51 MERC-CT]

The bosses are clearly spot welded to the sheet metal.
They can be removed by drilling out the spot welds and replacing with a fabricated (custom made) boss.
BUT I would consider 'HELICOIL' thread replacement. (before anything else )
There are kits available on Ebay as well as other vendors..

 

[BillW810]

The bosses are clearly spot welded to the sheet metal.
They can be removed by drilling out the spot welds and replacing with a fabricated (custom made) boss.
BUT I would consider 'HELICOIL' thread replacement. (before anything else )
There are kits available on Ebay as well as other vendors..

Good idea I've done helicoils before.

 

[BillW810]

The bosses are clearly spot welded to the sheet metal.
They can be removed by drilling out the spot welds and replacing with a fabricated (custom made) boss.
BUT I would consider 'HELICOIL' thread replacement. (before anything else )
There are kits available on Ebay as well as other vendors..

Do you think there is enough wall thickness for a helicoil? The boss OD is 0.375". The helicoil requires a 0.266 drill the there are the threads to be cut. I don't know the OD of the insert. Probably my best hope though.

Thanks,

Bill

 

[marko39]

Why not drill and to the next size larger?

 

[Phil Gillespie]

Why not drill and to the next size larger?

Thats the way I would go.
Phil NZ

 

[34PKUP]

Why not drill and to the next size larger?

Thats the way I would go.
Phil NZ

I suspect that the boss would disappear.

 

[51 MERC-CT]

Do you think there is enough wall thickness for a helicoil? The boss OD is 0.375". The helicoil requires a 0.266 drill the there are the threads to be cut. I don't know the OD of the insert. Probably my best hope though.

Thanks,

Bill

Sounds like it's cutting it close.
Might have to go to plan B.

 

[BillW810]

I suspect that the boss would disappear.

A 5/16 fine T-nut, another suggested repair, has the same OD as the boss. I guess over size drill/tap might work.