Supplied acorn nuts suck

[INTP_ty]

These acorn nuts suck. They end up grabbing hold of the stud & then you end up tightening the stud.

3 out of my 4 studs blew through the bottom.

Im switching to hex nuts btw. Can I just retap? And there’s no metric where I live. Anyone know the next “standard” size? I think there’s a tap/die set in the shop...,

 

[FurryOnTheInside]

Yes they do suck.
What do you mean by "blew through the bottom"?

If they screwed in until they broke through into the crankcase then there's no reason to tap anything, just bond the studs in place with loctite or JB Weld, as long as they are good (grade 8.8) studs you want to keep.

If you mean the threads are stripped out of the case then you need to get a Helicoil or generic thread repair kit for M8.

Buy nuts on fleaBay and don't use any loctite or anything on them.

 

[INTP_ty]

Yeah they blew through the crankcase.

 

[FurryOnTheInside]

Okay then. Can you be sure there's no chunks of aluminium dropped down into the crankcase? As long as there is nothing in there that could damage your engine and if your engine came with decent studs (Grubee and Zeda USA and idk which others) then you can just bond the studs in place.
Crankcase pressure is only 1.2 times atmospheric, I believe, so even blue loctite might be okay to hold the studs from spinning and as a seal, maybe. I would probably prefer JB Weld to be super certain.

 

[crassius]

These acorn nuts suck.

yeah, but they are sure 'nough purty

 

[Jroge1523]

That happened to me studs went thru case trying to figure out how to fix it without taking engine apart

 

[motorizedbikeguy]

There's no easy solution to this problem. You'll either have to helicoil or get a new crank case. The problem with helicoils, at least in my case, is the holes were too close to the edge, which will eventually result in cracking. After rebuilding my motor, I've decided that the best bet is to use stainless studs with something like red loctite where they screw into the crankcase. And then use washers and regular nuts, preferably softer than stainless.

 

[Frankenstein]

I definitely red tited several studs to stop that bulls**t before it starts, I like 2 brass washers on each stud and a normal flanged nut. If you are using a torque wrench then magically enough they don't strip, just make sure you have quality components..