I replaced my "Generator/AC Compressor and Power Steering Bracket". I was out in the garage putting things back together when I noticed that the serpentine belt is going to be off when everything is put back together. The Balancer assembly does not line up with the idler pulley, the tensioner, the AC compressor, etc... The engine was rebuilt months ago and I was doing a little R&R of the power steering hoses and putting in a new pump. (The engine was in a F-Body and I frankly have no idea if this is the proper assembly attached to the crank!)

It appears that the Balancer assembly (Harmonic Balance) is approximately .25" to .375" to far forward of the assembly. I am assuming this is not proper!?

Am I screwed or do I have options?

 

Let's start off with the year of your car and the year, make and model of the car the engine came from. Maybe then we can help.

Jake

 

Car is a 94 Coupe LT-1. 6speed.

Engine is a F-Body LT-1 Two bolt. I do not know what the donor car was other than a F-body

 

There are several variations I can think of with regard to the balancer hub used on LT1/4 engines. Two that are different is the F-body and Y-body as you unfortunately found out. The only real option is to get the right hub. I know a 96 hub will not work (shorter due to the reluctor ring), but I am not certain what the interchange is between 92-95. Lots of guys probably have them laying around after building a new engine or upgrading.

You may be able to use a spacer. Some aftermarket balancer companies offer a single hub, and then spacers for different applications. What it would depend on is if your hub is the one they used as the "standard". If the F-body hub happens to be the shortest of all the variations, you may be in luck!

 

Another members post gave me this idea...

Measurements
From the front of the Opti to the indention for the belt measured 1 9/16"
To the front of the balancer is 2 1/2" Plus a hair.

Anyone have a stock measurement so I can compare?

 

I recently found out that several 'F' body, LT1 parts aren't interchangable with the 'Y' body. I also learned that the oil pans, water pumps, and dampers are different. I've got a 'F' body oil pan and water pump in the garage to prove it.

When I recently built a new 388 LT1, I went with the ATI 917274 Super Damper so that everything would align. I guess you're going to have to get a hub/damper assembly that's specifically intended for LT1 'Y' body, unless there's some "work-around" I'm not aware of.

You might try calling the company that makes the hub/damper that's installed on the engine to see if there's anything that can be done. The SuperDamper is pretty pricey.

Sorry I couldn't help more.

Jake

 

F-Body Harmonic Balancer assembly different on the F-Body LT1?

 

Yep. Don't you have another thread running on this same issue?

Jake

 

Yes I do. When you have a "insatiable" thirst for knowledge you tend to do that sort thing.

 

Camaro/F-Body 2-bolt main LT-1 has a longer hub and a different balancer pulley.*

Mainly problem is that the longer hub used on F-Body LT1 will put the pulley too far forward to line up with the accessories. It will function for awhile but the reliability goes down the tubes when something comes loose. If anyone ever tries a engine swap and tries to put a F-Body into a Y-Body make sure the right hub and harmonic balancer are at hand.


*Source: Local Chevy parts Dept and Vette2vette.

 

There's a guy inquiring about buying the 96 LT1 I just removed from my Vette. He wants to install it in his Trans AM, so I warned him about that issue.

I also found out that the oil pans (windage tray) and water pumps (one more hose connector) are different, too.

Jake

 

Okay, here's what I came up with:

I took the measurements from a stock 1996 LT1 engine sitting on an engine stand.

I didn't use the Opti as a reference point because a couple of months ago I found that it's not a reliable reference point. I measured the difference between the stock LT1 I was removing from the car with the new engine I was installing (388) and used the Opti as a reference on both. There was a substantial difference in the measurements.

So, instead I used the block on both engines as the reference. Using the block, the measurements came out exactly the same.

I just returned from the storage locker where the stock LT1 is still on the stand assembled.

If you look at the front of the LT1 block, passenger side LOWER, you'll see two threaded bosses. I used the upper of the two bosses as my reference point.

From the upper boss to the REAR MOST point on the damper, the measurement was 3.25"

From the upper boss to the VERY FIRST (rear-most) serpentine belt groove in the damper, the measurement was 4.40".

I checked it several times using my digital caliper, being sure to ZERO the caliper first. So you can go with those numbers.

If you're using an aftermarket hub/damper the important number to look for is the distance from the block to the first belt groove in the damper. The thickness of different dampers may vary, but it's where the belt grooves are that'll determine if the belt and accessories will align.

Hope this helps,

Jake

 

Thanks Jake!

Looks like you took alot of time to do this. It is appreciated... I wish mine was not in the car right now.... Makes it alot harder! I now have to figure out how to get in a check my measurements.

I did speak to a local race mechanic. Knowledgeable guy. He told me to make sure that the pulley was tightened down! I was kind of assuming it was. I checked in and sure enough it was loose. I was able to get a few turns on it. It is closer but not directly on line with accessories. I thought I had it... It is starting to drive me a bit crazy!

I have a bunch of diagrams but I could use a few digital photos.... of the proper balancer.... Maybe I have the proper hub and the wrong balancer or vice versa?

I think I am mixing a drink!

 

Which pulley are you referring to?

The idler has (for lack of a better word) an aluminum extrusion (bump)which must index with a hole in the mounting plate (at least on my 96).

If you've installed everything correctly, all the bolt holes will precisely align.

Jake

 

Sure did. It was 102*F in the storage locker and the sweat was draining off me like someone was pouring a picture of water over my head.

See, this is what Forum members do for each other.

Keep us posted.

Jake

 

Another possibility could be the key in the crankshaft snout that positions the crankshaft timing gear. There are two different LT-1 keys and both are notched to clear the hub. The 96 key has about .150 less notch which provides additional key material to drive the 96's OBD-2 c/shaft position sensor trigger wheel. If a 96 key was installed in a 95 and earlier LT-1 it would prevent the hub from seating. Also, a standard replacement key with no notch might have been installed which would cause more of an issue.

 

Frustration leads to a bit of rambling.... so let me elaborate:

Harmonic Balancer was tightened tonight, the center bolt was a little loose. So this moved the Balancer slightly inward towards the block.

The idler pulley and the tensioner are properly mounted and torqued to spec as is the accessory bracket.

When I speak of alignment I am referring to the alignment of the entire serpentine belt system. If I look down into the engine compartment from the drivers side of the car the Harmonic Balancer is slightly forward of the pulleys and the other components in the sytem I would have to guess it is around .25" (one quarter of an inch).

I am pretty sure this is a greater variance from what the engineers intended for the serpentine system. I would have to take an educated guess and say that one of a couple of things can happen with this situation:

1. The belt will wear abnormally.
2. The belt will come off at higher rpm's
3. The belt could break as a result of #1.0

Is a .25" more than factory range. I am thinking so...

I would love to have a bone stock car sitting next to mine to compare. Oh well, I guess it is time to start shopping for a C5.

 

try to find a CF member that lives near you to drive by and show you his car side by side with your car.When I replaced the hub they wanted my vin # to make sure I have the correct part

 

I've never had to install a stock damper on a LT1 (I've done it many times on L98s and BBs) so I don't have any personal experience with the stock LT1 setup, BUT

When installing the ATI SuperDamper on the 388 I just built I had to use an installer to press it on all the way and I MEAN IT WAS A TIGHT FIT!!! No way would I have been able to press on the damper by using only the center bolt.

I'm running a Eagle crank that has two keyways for TWO Woodruff keys; neither key is notched like the one for the stock crank.

The damper fit was so tight on the 388 that the engine would turn over as I cranked on the installer tool's nut. I had to wedge a long, heavy screwdriver at the rear of the crank, wedged between the flex-plate bolts, in order to keep the engine from turning as I pressed on the damper.

I also had to use a big pipe wrench on the installer's nut to get the leverage I needed. I suppose I could have honed the ID of the damper to get some additional clearance, making the installation easier, but since the damper WOULD move on each turn of the wrench, I opted to continue.

You could be dealing with the same condition, needing to use an installer. If I read your post correctly, you were/are only trying to install the damper using ONLY the center bolt, right?

I used Anti-Seize on both the crank snout and the ID of the damper too.

Jake

 

Jake,

The damper was already on the engine and the engine in the car. I had a mechanic, obviously a crappy one, install the engine. Unfortunately, I did not work on it myself.

Yes, I was trying to tighten using only the center bolt. I guess I will need some help and another tool. Will I have room to pull this off with the engine in the car? I could use a recommendation on a tool to use for this task.