93camaroLT1

So I started putting my car back together yesterday and when I got to the hub I originally was trying to use a harmonic balancer install tool but the threads on it were far from long enough to get through the hub, so then I took a look at the haynes manual which just said to use the crank hub bolt with a large washer to get the hub back on but that bolt was just long enough to just start threading into the crank, so I just started threading the bolt in which was going in pretty much effortlessly so after I got the hub moving onto the crank I pulled the bolt back out to pull off that washer and to just put the normal washer that was with the bolt back on and the first four threads on the bolt came out silver and stripped, So today I just pulled the hub back off and sure as $hit, around the first four threads in the crank are stripped (looks like less than a 1/8 of the bolt)..

So what do I do now? Can I just drill the first four thread out of the crank with a 1/2" bit (the balancer bolt is 7/16" fine threads) and then it would just start threading normally from there? Or should I drill all the way through with the 1/2" bit and then tap in 1/2" threads??

93camaroLT1

Also would a thread insert be an option? (to keep it at a 7/16" thread.)

OBE1 95Z28

If it's just the first 4 threads, I think you'll be fine just cleaning them up with a tap and let the threads deeper in hold the bolt.

You don't want to pull on the hub via the crank threads Use a threaded rod that you fully seat into the crank. The with a nut and bearing, or a greased up washer and nut, "push" the hub into place by threading the nut. This way the threaded rod takes the abuse, not the crank threads.

93camaroLT1

By cleaning them up do you mean to go over the first four threads with a 1/2" tap?

Also, where do you get a 7/16" fine threaded grade 8 rod/bolt that is also threaded the whole way through????.... I looked just about everywhere just for a longer 7/16" fine threaded bolt (so that it would have threaded a little further onto the crank, hence not pulling out the threads.) with no luck.

lt1zpwr

whatever u decide just make sure to use threadlocker.....threadlocker is your friend

77LT1

Use whatever tap the threads in the crank are. I'm not sure what they are, but, you definitely DON'T want to use anything but the same size. Make sure you clean out what metal might be left in there.
You might try calling around to the auto parts stores and ask about what tools they loan out. Last resort would be all thread but I'd be worried about stripping the threads off of that.

Bryan

Dave89IROC

IIRC, they are 7/16x20

93camaroLT1

Alright... I gotcha.

So by "cleaning the threads up" I should just run the stock 7/16-20 tap through the stripped threads (first 4 threads), WITHOUT drilling, to pretty much just rethread the stripped threads.

1racerdude

Yes and make damn sure it's straight or ya will screw the other threads up and have to get it redrilled anyway.
Get ya an all thread rod to put it on with and screw it all the way in your crank and use the bearing from the installer and a nut and crank her on.
Ya could clean the hub real good and put it in a 300* oven overnight and get everything ready and run like hell to the engine and it will go on by hand if it is properly aligned.

93camaroLT1

How do I even know if it is going in perfectly straight?... I was thinking a level but the car isn't even sitting level, nonetheless anything else on it such as the engine.

1racerdude

Use your EYE---- Them micrometer eyes. Look at it from the top and side ya should be able to tell.
Use a straight edge off the crank top and side.

93camaroLT1

Where are you guys finding these all thread rods in a 7/16-20 size with a 7/16-20 nut??... I haven't found anything like that in that size, finding anything in 7/16 with a fine thread seems quite hard to find, definetly not something at the local ace hardware or menards.. Where do you guys go for these?

1racerdude

Lowes or Home Depot or a bolt supply house.