litch2004

iTrader: (1)

So i just took off my crank hub and on the crank there is a slot like there is a key that goes there but there isnt a groove for it on the hub. How do you know when you go to put it back on that it is on correctly?

redbird93

yeah our hubs arent keyed they just press on kinda sucks. there is no alignment

litch2004

iTrader: (1)

so....putting it back on is just a guessing game? Does it affect the the engine if it isnt perfect?

01fxst

Alignment doesn't matter since ours is just a pulley. I tried ordering a keyed crank adapter from Thunder Racing, but apparently they've been back ordered for months.

litch2004

iTrader: (1)

if i doesnt matter on how it is put back onto the crank then why do we have external balencers on our car?

litch2004

iTrader: (1)

doesnt it have to be placed on there just right to keep in enginge balenced?

shbox

We don't. The front has a harmonic damper, not a balancer. If you want to be able to gauge the crank position by the pulley arrow, you should put it on like it came off. Also, if any of the holes in the pulley are filled with a weight, it should be put back on like it came off. Some had very minor adjustments made at the factory. (I know, I know, but it is still not a balancer ).

litch2004

iTrader: (1)

o ok. i know which way it cam off because the key slot on the crank left a mark on the hub. So if it put it on there fairly close then i should be ok...right?

RamAir95TA

iTrader: (2)

Get it as close as possible. That way you can keep the proper orientation of the arrow on the balancer.

litch2004

iTrader: (1)

ok good. now when i go to replace the oil pan gasket (because it is leaking) how is the easiest way to do this with it all still in the engine bay?

SS RRR

iTrader: (2)

Is there any documentation with this? I would think it was more for zero balancing the damper rather than the engine. Especially since those that may needed to be tweaked did not end up with a keyed hub.

shbox

Yes, it is documented in the factory service manual.

GIZMO

iTrader: (8)

From the factory service manual 6A3A-13.

Crankshaft BALANCER Assembly and Hub.

A. Set number 1 piston assembly to top dead center.

b. Install crankshaft hub with cast arrow on hub in the 12 o'clock position.

SS RRR

iTrader: (2)

Technically the LT1 is internally balanced (at least most of them) on the front and externally via flywheel/flexplate in the rear.

GIZMO

iTrader: (8)

lol!!

shbox

Neutral in the front and external balance in the rear, that's right.

The hubs and pulleys should be neutrally balanced. It was only in the case of "fine tuning" that the factory put any weights in the pulley. That is why most people don't have an issues when installing the hub in any which way. Of course, if you change any of the rotating assembly, it no longer matters anyway.

GIZMO

iTrader: (8)

I have a new GM Corvette and a new F-Body balancer. The Corvette has balance holes drilled and the F-Body has metal added (balance weight). Have you ever noticed that the hub and balancer only go together one way? I guess that GM did that by accident? And when they wrote installation instructions in the shop manual it should have said, "If you want you can install it this way"? At 5200 rpm it probably won't make a difference what you do, but if you install a bigger cam and up the rpm's it will probably beat the crap out of the motor over time.

litch2004

iTrader: (1)

Thanks for the imput but as far as the oil pan gasket goes how hard is it to change with engine in the bay and cross member still installed.

SS RRR

iTrader: (2)

Not true. I ran a stock balancer running to 6100 almost every day when my car was a daily with LPE heads/cam. Ran that setup for 70K miles. Tore the engine down years later and the crank/rod bearings were pristine. Same thing after I installed an 847 cam and ran that for a few years turning 6500rpm on the stock block. Tore that block down and bearings were like new.
I'm running an aftermarket stockish type damper now (can't remember the brand name) and turning 7100rpm. I have all the faith in the world it will be fine. I also have faith there are thousands who've run the stock damper, installed it however, ran it past 5200rpm with great success.
I fully believe GM states that just to cover their *** in case of any sort of bottom end problem. I was told by some of the rockstars at Lingenfelter the LT1 was indeed internally balanced in front and externally in the rear. I think if you ask anyone who is familiar with the LT1 you'll get the same response. My engine builder, who has been building LT1's for the last 9 years also states the same. If you'd like to find out for yourself you can call them.
Burtonsville Performane and Machine:
(301) 490-3131

shbox

If you are disputing that LT1s are neutrally balanced on the front and externally balanced on the rear, I don't know what to tell you. All that I have read from a lot of people (incl engine builders) over the last 10 years says this is correct.