Front Crankshaft Bolt Idea

[jeepxj3]

The crankshaft front snout seems to be a weak area and has broken off for some guys in the past. Threading in a bolt is weak at best and if trying to use the bolt instead of a proper pulley installer will break off a piece of the snout.

What about drilling the snout hole deeper into the crank, ? 4" deep, and threading it all the way in and installing a threaded stud into it. Then use a nut on the end to secure the pulley.
The longer stud will strengthen the snout, maybe help with harmonics, IDK.

[IH 392]

First I've EVER heard of this "issue"??
Of ALL the broken crank shafts I've ever seen I' don't recall ever seeing the snout broken off of one, of ANY make or model??

Using the bolt as a puller/installer might just pull the threads out of the snout.

[SilverXJ]

It is not an issue. I heard of it happening once for sure, maybe twice. Not common by far.

Using a threaded rod/stud will not help with harmonics. Make sure your balancer is in good condition and really balanced. Many do not come with a real good balance.

Do not pull the balancer on with a bolt. Rent or buy a correct balancer installer. While ARP doesn't offer a bolt for out balancer there is one from a Chevy that will work if you just want an upgrade. IIRC its a BBC and may need a bit of the end shaved off. The Part number should be in the last few pages of my thread.

[gradon]

My first crank's snout snapped shortly after a harmonic balancer separated. I was stranded at night and did use the bolt to pull in the new hb, which partially stripped the first few snout threads. I then used a too-long bolt with washers so I could engage more of the snout's good threads. I suspect I bottomed out the bolt. It was fine for a few months, until I downshifted into 3rd while racing a GL-450 and heard the clunk of the hb leaving. Luckily, I had a spare crank. Anyhow, not an issue to be worried about.

[SilverXJ]

My first crank's snout snapped shortly after a harmonic balancer separated.

I thought that was you, but wasn't 100% sure.

[jeepxj3]

That is what I was picturing for breakage. Drilling further into the crank another 2-4" and then thread in a long stud, like a head stud.
The above breakage wouldn't have happened with this longer stud in place.

[gradon]

Basically I was at fault for the snout snapping. It is not an issue and you could very well weaken it by drilling it. Focus your energy on other parts.

[SilverXJ]

x2 Install the harmonic balancer and bolt correctly and there is no issue.

[jsawduste]

The factory HB was designed for specfic application the rod length, crank weight and stroke.

Think ATI

[amceaglesx4]

WOW that's fucked up !!! That definitely is a shitty day. I've never heard of something like that happening. How tight did you make that belt ?

[6TIME]

Like others have said, check for bottoming of crank bolt... Shouldn't be an issue. Btw an aftermarket tall hex head crank bolt for BBC works excellent for the 4.0/4.6. When turning the crank over with socket it stays put and doesn't try to roll off as with the factory bolt.

[SilverXJ]

I have the APR tall hex head bolt for the BBC. In addition to the taller hex it also has a spot for a 1/2" drive ratchet. It works great.