Oil level sender bolt/stud on oil tank sheared

[Ian France]

Hi All
Greetings from France
Ive just snapped one of the five studs/bolts holding the Oil level sender to the oil tank of my 1983 SC
I had just replaced a leaking gasket (new nuts new washers )and all looking good just slight weeping still once engine warm so a small tighten up all round - Very little torque really (small wrench, wrist only, wheel still in place even ) but the last bolt just snapped off at the base.
Is there a way to get those studs or bolts or whatever they are out and replace them ?
Ive got a horrible feeling this is going to be a very expensive gasket change!

Cheers
Ian

[Walt Fricke]

Ian - I'd start by removing the sender, and placing some kind of gasket cement on both sides of the gasket, and then putting things back together, letting the cement set, and crossing fingers. The four are plenty adequate to hold the sender in place, so the only question is whether they will compress the area over by the broken one enough.

Most of the ideas which come to mind for a fix require draining and removing the tank, as you really have no room to work in there. With the tank out you have various options, with perhaps the most sensible being drilling out the broken stud, threading the drilling, screwing a new stud in, and welding (or brazing) it in place. Lots of effort, but ought not to be too expensive if you do the R&R?

Or you buy a good used tank. The thing I look for in tanks is the condition of the drain plug threads. I have two where they are stripped. Various fixes for this, but kind of destroys the idea of swapping in a good tank.

[Ian France]

Thanks Walt
Will certainly try the gasket cement and finger crossing first -but failing that are they really just normal studs? what are they screwed into?
Ian

[Walt Fricke]

As far as I know from dealing with them (though not with the idea of how to replace one), they are welded or brazed into place. They may be like bolts with a thin round head, not a hex, and welded on the inside of the tank and sticking through. Or welded to the outside of the tank. But not like a stud which is screwed into a tapped hole. The tank metal isn't thick enough for that, and so on.

Even if it were a stud, what is it - 6mm? Or 5? Very hard to drill a stud like that to get an extractor to work. Hard to center a "backward" rotation drill bit to let that help coax the broken part out before the extractor is used. And you'd have to be way more skilled than I do be able to drill a hole into that with the tank in the car. I bet this isn't a full on race car with removable rear fenders.

I guess, if glue doesn't work, or reduce the leak to a manageable moist (and dirty) area on the outside of the tank, there is a sort of kludge not requiring welding.

Take out the tank, drill out the broken stud (using a fairly small drill, and being careful to catch the shavings), put things back together, and use a big enough sheet metal screw (liberally gooped with sealant) to do the fastening. There really isn't much stress on this system, so tightness goes to compressing the sealing gasket, not for holding up something heavy. But, as I said, a kludge.

Or maybe someone who has dealt successfully with this problem will chime in.