Hey guys I have one stripped thread on the lim. What would be best approach? Should i just get a 9mm 1.25 bolt or drill and insert recoil?


I bought this but dont like how big a hole i would need to make. Maybe just go the next bigger bolt



These inserts dont look long enough either

 

if its not too bad, maybe you could locktite a stud in there?

 

General rule of thumb for helical inserts is the length of the helical insert should be at least 1.5 X the diameter of the fastener thread, so a 12mm long helical insert should suffice.

im becoming a big fan of helical inserts, but just look up how large the “removed material” would become, also known as the major diameter of the tapped hole which the helical insert will be inserted, which is simply about the outer diameter of the threaded insert.

then I size up a caliper over the stripped hole to see how large the threads will cut into the manifold and see if it’s an option.

Then you need to check wall thickness. I’d have to defer to the machinists handbook but I’d probably feel safe with as low as ~.075” wall thickness from the wall to the major diameter of the threaded internal hole which the threaded insert will be inserted into.


Option 2, look up the minor diameter of a threaded 9mm hole (or even go to standard thread sizes) and see if that’s greater than the major diameter of a 8mm threaded fastener, to see if you’d start fresh and have no remnants of the 8mm internal thread.

 

thank you. Im going to look for a m9 1.25 bolt and see if that would work first. Ace sells a m9 1.25 tap so they might have a bolt too. Im just not comfortable making a bigger hole on the surface of the gasket. I need to drill it with a 21/64 and realised it'll be alot of material off.

 

I would invest in a timesert so you can use the same thread pitch as the original bolt. It's a stronger helicoil. Comes with the drill bits and tool so it's a perfect fit.

 

I was unfamiliar with timeserts so I looked into it, $90 to fix this problem is pretty steep.

 

Heli coil is the best solution (they can be stacked for more engagement), least amount of material removed, just make sure you use the correct drill, use the installation tool, and knock the tab off, I like to blow it out of the hole with compressed air.

If you wear the Heli coil out, you can go Keen-sert.

The tap in that kit sucks ***, they all do (same with Home depot, Lowes, Ace, etc) bought that way, go to MSC and get a good tap or, be very, very careful.

 

@TonyD89. So i could stack the helicoils. The hole goes through. I bought an m10 1.25 bolt and too thick. It will require me to drill the UIM and i dont like that. If i could stack the helicoil. Then it might work better. I still wanna find an m9 1.25 just too see if its even possible to fix it that way.

 

Is the through hole long enough? They get longer when installed. I don't know exactly by how much, but they do.

Keensert, the advantage is the outside thread is a standard tap, not a helicoil tap.

https://www.carrlane.com/product/threaded-inserts

 

If you're saying there may be an untapped part of the hole at the bottom, yeah, tap it through and use a longer bolt, if there's room, put a nut on the other side.

 

@TonyD89
I bought a longer bolt. The flange nut won't fit under. Might need to get a smaller non flange nut and grind it down a bit. Then tried the flange nut on top and actually holds 14lbs torque. Would be better to try the nut on the bottom once I grind it down a bit.

 

If it works, it works. You can always helicoil it. At 14 ft lbs, one should suffice, no need to stack them. Jam nuts are thinner than regular nuts.