LT1 Harmonic Damper Question
Thread Starter
Racer
Joined: Feb 2001
Posts: 381
Likes: 8
From: NORTH WEST PA
LT1 Harmonic Damper Question
Is it possible that a LT1 harmonic damper did not have any weight added to it from the factory? I noticed a picture from an earlier post of a LT1 harmonic balancer that had 3 weights installed.
Thanks
Brian
Thanks
Brian
Race Director
Joined: Jan 2002
Posts: 12,264
Likes: 88
From: O'Fallon Missouri
HUB AND BALANCER
The balancer is a two-piece assembly with a pulley that bolts onto the hub. Separating the two made it easier to install the Optispark distributor on the assembly line and out in the field. The holes in the hub are offset, so the balancer only fits on it one way, but there’s no keyway in the hub to index the hub on the crank. This shouldn’t be a problem unless the damper was drilled at the factory to "trim" the final engine assembly.
If it was drilled a lot to compensate for an engine that was out of balance, you could end up with a shaker, depending on how everything stacked up with the remanufactured engine compared to the original engine. If you encounter a balance problem on a remanufactured LT1, try rotating the balancer assembly on the crank 90° at a time to see if it eliminates the problem.
The balancer is a two-piece assembly with a pulley that bolts onto the hub. Separating the two made it easier to install the Optispark distributor on the assembly line and out in the field. The holes in the hub are offset, so the balancer only fits on it one way, but there’s no keyway in the hub to index the hub on the crank. This shouldn’t be a problem unless the damper was drilled at the factory to "trim" the final engine assembly.
If it was drilled a lot to compensate for an engine that was out of balance, you could end up with a shaker, depending on how everything stacked up with the remanufactured engine compared to the original engine. If you encounter a balance problem on a remanufactured LT1, try rotating the balancer assembly on the crank 90° at a time to see if it eliminates the problem.
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Originally Posted by RED92LT1
Is it possible that a LT1 harmonic damper did not have any weight added to it from the factory? I noticed a picture from an earlier post of a LT1 harmonic balancer that had 3 weights installed.
Thanks
Brian
Thanks
Brian
Thread Starter
Racer
Joined: Feb 2001
Posts: 381
Likes: 8
From: NORTH WEST PA
Thanks for the replies.
My engine has not been rebuilt or replaced and didn't always vibrate, and I can't say when it started. I did an OPTI replacement last year, but it was vibrating above 3000 RPMs before that.
However, when I did the OPTI I noticed a white line on the damper, almost like a factory mark. When I reinstalled the damper I lined the damper to the hub as specified by the Helms manual. I never looked to see if the damper had been drilled to facilitate a non standard installation.
I'm planning on pulling it apart to see if anything looks out of place or worn.
Thanks again ... any and all comments are very much appreciated.
Brian
My engine has not been rebuilt or replaced and didn't always vibrate, and I can't say when it started. I did an OPTI replacement last year, but it was vibrating above 3000 RPMs before that.
However, when I did the OPTI I noticed a white line on the damper, almost like a factory mark. When I reinstalled the damper I lined the damper to the hub as specified by the Helms manual. I never looked to see if the damper had been drilled to facilitate a non standard installation.
I'm planning on pulling it apart to see if anything looks out of place or worn.
Thanks again ... any and all comments are very much appreciated.
Brian
