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Discussion Starter #1
I need a new harmonic dampener.
During my research, it sounds like it best to pin the crank to the dampener.
I happen to have a drawer full of hardened 1/4" dowel pins in a few different lengths.

What is the diameter and length of the crank pin that is used in the LS1?

I can probably make a drill guide fixture, but need to know how long of a pin is normally used. I don't want to put in a 1/4" dia. x 3/4" long pin if the norm is something different.

The other thing I will find out is if there is enough room to get a drill in there with the engine in place.
I don't have a stubby drill. I do have a right angle die grinder that I might be able to fit a drill bit in.

Thanks,
Rich
 

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Most use like 3/4 inch deep.

Drill straight and not too deep to prevent oil leaking issues.

You must move the steering rack out of the way as there is not enough clearance which is a big job as several other parts have to also come out

You also need to remove the starter and use a tool to flywheel to prevent it from turning when installing a new damper bolt. that is torque to yield type.

You need a good strong drill and sharp drill bit as crank metal is pretty hard.
Do not use a air pressure type socket tool as the banging it does can cause the crank position sensor to get out of wack causing a ton of false misfires.

Most times a damper is loose is people not properly installing bolt when changing CAM or timing chain
 

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Discussion Starter #3
Thanks for the info.
Is 1/4" diameter correct for the pin?

I was reading somewhere where the guy made a tool to hold the balancer while loosening the bolt. He used a piece of 4" pipe and cut some fingers in it that fit in the balancer holes. He put a piece of tube off the side like a handle that rested on the frame.
I'll probably make a similar tool.
I run a steel fab shop, so I have access to all types of materials.

I need to make a decision on the balancer to buy and get things going.
 

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Damper pins sold come with a reamer that is needed after drilling and is 15/64 inch (0.2344)
Without seeing that home made tool can not see how it works when installing and proper torque sequence of bolt.

You could make a tool that meshes with the teeth of flywheel and uses the starter mount bolts to assure no movement as bolt is torque to yield and can only be stretched correctly once.
 

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Discussion Starter #5
Ok, so you are saying some kits supply a drill bit and also some sort of reamer?
The few pictures of the pinning kits I've seen look like they only have a drill bit.
I suppose I could drill the hole undersize and start stepping it up until I could drive the pin in there.

Basically, the tool to prevent the balancer from turning is a piece of pipe with a lever hanging off the side. Your socket for the crank bolt passes through the end of the pipe. (Think concentric circles.)
You prevent the pipe and therefore the balancer from turning by allowing the lever to go up against the chassis or some other non movable item on the car.
Works similar to the tool used to loosen the nuts on front shocks or the tools you see for adjusting valves.

I'm aware of the torque to yield factory type bolt. I have a torque angle gauge, but haven't used it in years.
I plan to use an ARP bolt.

Since I'm not getting any response yet to my balancer brand thread, got any preferences for a balancer in the $200 range?

Thanks,
Rich
 

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The reason a reamer comes with is to assure smooth proper fit as again if you do any real hammering to get pin in flush you could damage crank position sensor and if it cannot be resync'd with PCM the reluctor wheel is around crank and could require you getting to crank.
After drilling the round reamer rod allows to smooth and slightly enlarge hole until pin slides in with a bit of red locker.

Also later on when you need to take damper off you do not want pin jammed in.
The crank bolt flat of head covers pin so easy fit with a bit of locker on it is all needed.
Pin kit I get comes with pin, drill bit and reamer.

I do not suggest a smaller damper as it effects ALT output and the electronics for powertrain really rely on voltages around 14 volts so stock one is fine as not normal for them to go bad unless some type of boost was added.

Once steering rack is taken out there is not a lot there to jam some bar from turning but you'd know better when your under there how to make your tool but I tried one of those torque multiplier tool used for like wheel lug bolts and broke the tool trying to get damper/crank bolt loose.

Much better with a tool locking flywheel from turning
 

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Discussion Starter #7
Thanks again for the info.

There is an alternator overdrive pulley made by ASP #540120.
Maybe I'll go that route.
 

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So why not just put it back like the stock setup?
 

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I still have my LS1 crank pin kit. It has the drill bit, reamer bit, crank snout fixture with drill bit guides and lock nuts for the guides. I may have a pin as well. The kit comes with 2, I'd have to look to see if it wasn't misplaced. But if you want it PM me and we can arrange something.
 

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I still have my LS1 crank pin kit. It has the drill bit, reamer bit, crank snout fixture with drill bit guides and lock nuts for the guides. I may have a pin as well. The kit comes with 2, I'd have to look to see if it wasn't misplaced. But if you want it PM me and we can arrange something.
That sounds a lot better than fabricating something.
 

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Yeah, it really is. And if I can't find the pin a new pin can be acquired from ATI for less than 3 dollars.
 

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Discussion Starter #12
So why not just put it back like the stock setup?
No other reason than the dampeners I'm looking at are underdrive. At Texas Speed they have some TCI dampeners. The stock pulley one is $40 more than an underdrive. Most of the concern with underdrive pulleys appears to be turning the alternator fast enough at idle to charge up the battery and run accessories.
For $25 I can buy an alternator overdrive pulley and still benefit from the underdrive of the water pump. Even if there is no benefit, I still come out $15 ahead. I may just go with a 10% underdrive and call it a day. I already know the correct belt to get for it.

As far as fabricating fixtures and other things, for the last 12 years or so, I've been into the '80's Starions/Conquests. There is practically no aftermarket for them and hardly any parts from other cars are interchangeable. If you want something different or want to make more power, you either find another club member that makes a part or you make it yourself. I've made several parts from adjustable roller rocker arms to TPS adapters.
I guess that's part of the enjoyment for me working on cars.

Thanks for the offer on the ATI pin guide kit.
I'll have to do some thinking about it.
I see the ATI kit pins the crank from the side. I was going to pin it from the end. That explains why there is a precision reamer with the kit.
I'm now second guessing myself with pinning from the end. Pinning from the side will allow me to change the balancer to a better model in the future if I decide to go crazy with a supercharger or something like that without having to worry about a unique pin location.
I also found the ATI's use a 3/16" pin. I'll bet 3/16" is the standard key way.

Thanks for the comments thus far.
It's best to listen to comments from many sources and device a plan that suits your situation.
 

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I don't know enough about this stuff to get creative. I let someone else come out with a better mouse trap, catch a **** load of mice and then sell it to me.

Hell, they gotta eat too! :laughing:
 
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