heli coil on crankshaft?

[79ON40s]

I just got my rebuilt small block back from local engine builder, I went to put the harmonic balancer on last night and a 7/16 bolt does not want to thread in the end of the crank, started looking and there is a heli coil in there, would you guys trust it if i find the right bolt? it kinda worries me on what else he cut corners on.

 

[Never Satisfied]

I have found that if done correctly, a heli coil will be as strong as cut threads. Are you sure the pitch on the coil matches the bolt you're trying to use.

 

[blazinzuk]

I have heli coiled a crank before and it worked fine. We did it cause the P.O. had threaded in a course thread bolt.

 

[79ON40s]

i used a 7/16 fine thread bolt, which is supposed to go in there, i am going to try a coarse thread bolt since most heli coils are coarse thread. there is not much stress on that bolt since the balancer is basically pressed on. thanks for the input, it makes me feel a little more comfortable with it

 

[vortec]

i wouldn't say the guy cut corners. i've seen helicoils used in various parts of rebuilt engines many times and they're ususally fine. in mine, i pulled the helicoil (not on purpose, long story) and used a larger bolt. works perfectly

 

[big dan]

I helicoiled one of the holes for a head bolt one time with no problems. If done right then I think they are plenty strong enough.

 

[vortec]

If done right then I think they are plenty strong enough.

and, the bolt on the end of the crank doesn't have that much force applied to it, anyway. the balancer pretty much holds itself in place. the bolt really seems like a formality to me. i've seen a few people run without it and the balancer stays on fine as long as the key is set in there tight enough.

 

[79ON40s]

yeah, thanks for the replies, from here, as well as doing some research and talking with others, i feel much more comfortable running a helicoil, the only problem is that I was trying to thread a standard size bolt into a fine thread helicoil, its tough in this town to find a fine thread 7/16, but i got one and hopefully it should work just fine. again thanks for the help, i need to muster up the $25 to join, but right now this engine swap is cutting into my play money too much