ahritchie

iTrader: (1)

So what I thought was a bad alternator looks to be like the harmonic balancer on my new 383 just took a ****....the outside "ring" is loose as hell and has tons of play. It caused my belt to be ripped to shreds which I though was because of a bad alternator bearing and it was not charging. This pos has less than 2000 miles...what are my options for fixing this? Or do I have to buy a new one? To top it off somebody canceled their dyno appointment next monday at PCM for less so I took it....need my car on the road this week

ahritchie

iTrader: (1)

Oh yea, its a Professional Products aftermarket balancer as you can tell by the pic. Are these known to come apart like this Should I put the stock one back on Whats the stock one rated at RPM wise anyway? I won't spin it past 6500rpm or so?

BALLSS

if the stock one is still good..it will work. Be the quickest fix

I run the ATI

Fazz73jr

iTrader: (3)

I've run my stock one to the 7000rpm pcm limit without issues. Although its in great shape I don't know how long it will last at that kind of rpm.

I've had a few professional products balancers for regular old sbc and bbc without any issues. The sbc seen a occasional 8k rpm and seen 7k countless times. No issues.

Id swap the stock one back on as long as its in good shape and run it

bowtienut

iTrader: (1)

I'd prefer the stock one over "Professional Products" any day. That brand may be ok for simple "nuts and bolts" parts, but I wouldn't trust them where any technology or science comes into play; cheap Chinese junk.
I don't know what the stock damper is rated at, but I know a lot of people spinning them to 6500 for years without issues. One caveat though: If it's your ORIGINAL stock damper, the elastomer could be degraded/brittle just from age. Poke around on it and compare to the "new" rubber in the failed damper. You might want to buy a new stock one if you intend to leave it on there indefinitely.

ahritchie

iTrader: (1)

Ok...the stock one I have is in a lot better shape ha ha. I'll go with it for now I took the Professional products one off....there's no rubber left, the outer ring is completely separated and the bolts were backing out; damn Chinese workmanship LMAO Let this be a lesson to others to avoid Professional Products shoddy POS garbage product. No wonder I was hearing all this damn banging and knocking when my "alternator died"...see how much play was in this thing

ahritchie

iTrader: (1)

If it's not one thing it's another.....the Professional products crank hub has a peg that sticks out so you can't bolt up the stock balancer to it. What should I do? Grind off the peg and try to make it work with the stock balancer or do I have to replace the whole crank hub with the stock one What tools are needed for that? What a PITA!

ahritchie

iTrader: (1)

This is getting ugly and more complicated by the day; it turns out my no longer stock 383 LT1 shortblock was both internally AND externally balanced by adding some weight to the flywheel and DRILLING SOME HOLES in the harmonic balancer (see pic)to remove weight (possibly compromising the rubber in the balancer from heat). Does this mean I have to have the replacement balancer (stock) balance matched to the old one Is that even possible anymore that the rubber has disintegrated and the center of the balancer free wheels around? What are my options? Pull the damn motor and have the whole thing rebalanced?! This sucks....experts please chime in.

SS RRR

iTrader: (2)

The easiest thing to do is to get ahold of whoever built the engine. They should have given you a build sheet to tell you of such things. My only ideas are those holes aren't for the engine, but rather to zero balance the damper. If the builders followed stock balance protocol, the engine is indeed externally balanced in the rear via flywheel/flex plate and internally balanced up front along with using a zero balanced damper. People have argued by claiming the holes they see in their damper are indeed to balance the engine, and then state "... but I compared it to another damper and the holes are different." It's crap. Stock dampers need to be zero balanced and the holes will not be in exact locations from one to another. With all this mumbo/jumbo stated, I'd either call the engine builder. If no information can be divulged then I'd take the damper to a machine shop, have it spun to see if it is indeed zero balanced or not.
Is the crank keyed for your damper/balancer?

bowtienut

iTrader: (1)

Those 4 holes are there to balance the damper itself. No, they didn't contribute to the damper failure.

With the exception of that counterweight on the flywheel, your engine IS internally balanced, just like all SBC's with the one piece rear main seal.
Many aftermarket rotating assemblies are completely internally balanced and don't require that weight on the flywheel, but yours obviously isn't one of those. Regardless, the flywheel weight has nothing to do with your issue at hand.
Don't over-think this. Just replace the hub and damper.

ahritchie

iTrader: (1)

Ok....guess I'm panicking because I don't know much about engine balancing and I wanted to get this fixed ASAP for the dyno on Monday. Per Kenny who I bought it from here on the forum: "The rotating assembly was balanced as one unit. The shop that balanced it needed to add mallory at the front counterweight of the crank, and offset it at the balancer (it was drilled to remove weight)."

Hopefully he'll chime in to clarify. There looked to be a little wear on the 140k stock crankshaft hub....is it safe to reuse?

I haven't checked personally, but by googling the part it does appear to be keyed: http://www.spiderautomotive.com/8003090030.html

ahritchie

iTrader: (1)

Is this the best method for replacing the crankshaft hub/balancer? Suggestions?

http://www.lt1engines.com/tech/remov...lt1-crank-hub/

SS RRR

iTrader: (2)

If the damper is really a balancer it should be keyed so you don't have to worry about putting it in any specific position. Check the crank shaft to see if it's keyed. If it isn't then you need to have it keyed for an actual balancer. You need to get a keyed hub.
I think you have a six speed? If so, no need to use a chain. Just put trans in 5th gear with the e-brake on (as long as driveshaft is connected that is) and that will be enough resistance to do whatever you need to.

ahritchie

iTrader: (1)

Why would I need a keyed hub if I'm going back to the stock crank hub and balancer? The stock hub is not keyed. Yea, its a 6spd.

BALLSS

stock hubs are not keyed. bring #1 cyl to TDC and press on hub with the "pointer" part at 12 o clock. Actually it doesn't mater what orientation you press it on but "stock" that is how they align it. Non keyed it does not matter. Keyed hub only goes on one way.

if you want a good high $ balancer..get the ATI

ahritchie

iTrader: (1)

Ok...thanks for the clarification. Can I use a piece of wood and beat the hub on with a hammer or do I really need a special tool or press?

AChotrod

iTrader: (17)

If your crank is keyed the stock one wont work. Well at least mine wouldnt.

ahritchie

iTrader: (1)

LMAO damn this **** gets confusing once you get so far from stock....I thought the stock crankshaft was keyed too Guess I will have to take of the Professional products hub and find out if the NEW 383 crank is keyed or not (I would assume so).


Back to a previous question though....could I grind off the small metal peg on the aftermarket professional products hub preventing the STOCK balancer from mounting; basically just using the aftermarket hub already on the motor and STOCK balancer Or do I NEED to use both the stock hub and stock balancer together

This thread makes my brain hurt.

SS RRR

iTrader: (2)

If your balancer is an actual balncer then you cannot use the stock damper. The stock damper is zero balanced. You would need a balancer that is balanced the same as what you just took off. It needs to be keyed so it does not slide out of position.

ahritchie

iTrader: (1)

Ok...I think I'm understanding this finally I just need to find out if the broken aftermarket professional products balancer was zero balanced like stock so I can go back to stock hub and balancer or NOT zero balanced which would suck since I have no idea how a machine shop could balance match a new balancer to the old one now that it's separated into 2 peices Or can they?

Am I understanding this correctly?