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Question regarding balanced flywheel by headhunter
Started on: 01-18-2004 11:46 PM
Replies: 4
Last post by: theogre on 01-19-2004 03:22 PM
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Report this Post01-18-2004 11:46 PM Click Here to See the Profile for headhunterClick Here to Email headhunterSend a Private Message to headhunterDirect Link to This Post
My flywheel was from the wreckers, for a manual. Anyways wondering if its balanced, without having to go to machine shop. If it were, would it have little divets taken outta the plate? It looks like someone just took a drill to part of it to take out some weight to get it balanced. Could be wrong.

Thanks for posts in advance.


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Report this Post01-19-2004 01:36 AM Click Here to See the Profile for aaron88Send a Private Message to aaron88Direct Link to This Post
One of the easiest ways to tell if a flywheel is supposed to be balanced or not is to look at the bolt pattern. If it has an evenly spaced bolt pattern then it is most likely a balanced flywheel, unless of course there is a keyway somewhere. The basic reason that a keyway or offset bolt pattern would exist on a flywheel is to make sure you have the weighted part of the flywheel in the right place.

However if it looks like someone has tampered with you flywheel Id not use it at all.



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Report this Post01-19-2004 08:08 AM Click Here to See the Profile for GTClick Here to Email GTSend a Private Message to GTDirect Link to This Post
I don't know how to tell the difference between balanced or otherwise, but I can tell you that the "neutrally balanced" flywheel I just bought from the dealer for my TDC has the same type of holes drilled in it that you describe. They sort of go about 3/4 of the way through. One other thing I can add is that if your flywheel is from an 85-87V6 it will only work on an 85-87V6. The 88 has a "neutrally balanced" flywheel and costs close to $300 from the dealer and is not compatible with the earlier flywheels.

-Rick Stewart

85GT Turbo 3.4TDC/5-speed in progress

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Report this Post01-19-2004 09:19 AM Click Here to See the Profile for avengador1Click Here to Email avengador1Send a Private Message to avengador1Direct Link to This Post
The pre-88 flywheels have a weight cast into them. To make it neutraly balanced that weight has to be machined off till it is even with the rest of the flywheel.
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Report this Post01-19-2004 03:22 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreDirect Link to This Post
All flywheels are balanced. That is what the drill holes are for. If they weren't balanced, the engine would literally shake apart in no time.

In general, most flywheels are "neutrally balanced" meaning they do not play a role in crank balance. The crank and flywheel are balanced separately.

For some reason only god knows... GM used the flywheel to balance the crank on some V6 models. In this case the crank and flywheel are balanced as an assembly if you want the best balance posible. This has always been a nasty way to balance a crank.

Note that if the crank balance wheight is milled off on the flywheel, the flywheel needs to be rebalanced. Simply milling it even isn't accurate enough. Even small amounts of imbalance can shorten engine life considerably.

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Murray: Since it was invented.

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