How to fix broken bolts from the sewage basin lid? Do i need a new basin?

[Carl Hudson]

How to fix broken bolts from the sewage basin lid? Do i need a new basin? Two of the top bolts broke off when i was removing the lid and two others i had to cut off. Is this something that can be fixed?

 

[MKS]

You could try soaking the bolts with a product for the purpose. PB blaster, automatic transmission fluid or such over a number of days.
Center punch the center of the bolt.
Drill a hole in the bolt to the size required for a screw extractor and back it out.
I often start with a smaller bit being careful not to break it.

 

[Sponsor]

 

[Jadnashua]

Worst case if you can't loosen and remove the bolt is to drill it out and install a helicoil if there's enough metal left to support it. That requires special drill bit, tap, and installation tools. Trying to centerpunch a broken off bolt can be problematic since it's likely not flat...the centerpunch tends to slide. The hole must be relatively well centered in the bolt shank or you'll end up damaging the threads when you try to drill it out. If it sticks out some after top removeal, sometimes, filing it a little bit flatter or a touch with a grinder can make it easier to get the centerpunch to go where you want.

Note, if you've not used a removal tool (one brand is EZOUT), they are quite hard so that they can cut into the hole you drilled, but as a result, they're brittle. If you break it off, it's nearly impossible to then drill the bolt out.

If there's enough metal, and the old bolt is just too rusted in place, you could drill and tap it for the next bigger bolt diameter. You might want to consider SS or brass, which is less likely to rust/corrode in place.

 

[JRC3]

You could try soaking the bolts with...automatic transmission

You mix ATF 50/50 with acetone. Many believe this works better than PB or any other store bought penetrating oil.

http://www.mtfca.com/discus/messages/411944/499019.jpg

“Machinist’s Workshop” recently published information on various penetrating oils. The magazine reports they tested these products for “break out “torque” on rusted nuts and bolts. A subjective test was made of popular penetrating oils, with the unit of merit being the torque required to remove the nut from a “scientifically rusted” bolt. Average torque load to loosen nut:

No Oil used ……………………516 foot pounds
WD-40 ………………… ……..238 foot pounds
PB Blaster …………………….214 foot pounds
Liquid Wrench ………………….127 foot pounds
Kano Kroil …………………….106 foot pounds
ATF/Acetone mix…………………. 53 foot pounds

The ATF/Acetone mix is a “home brew” mix of 50/50 automatic transmission fluid and acetone. Note this “home brew” released bolts better than any commercial product in this one particular test.

 

[Cacher_Chick]

It would be helpful to know what kind of basin you have, as they have been made in steel, cement, fiberglass, and plastic. Most of the newer ones are fiber reinforced plastic, and have brass threaded inserts.

 

[tedn332]

If the tub is set in concrete and the rim overlaps that, drill a new hole beside the rusted and use a "tapcon" or similar masonry screw.

 

[FullySprinklered]

One of my pet peeves. Best thing to do is to reuse the bolts that will still function, then work your way around the lid with drywall screws and washers to seal the lid down. Those nuts in the tank flange spin out and become nonfunctional quite often. Repair would be an exercise in frustration, most likely. Run a rubber or foam strip around the flange if necessary when refitting the lid, or a bead of silicone if the original seal is wonky.