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Front end play mystery -bad flywheel

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Old Jun 18, 2017 | 08:08 PM
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Front end play mystery -bad flywheel

I had this issue on my rx8, but wb the same issue with my TII, so thought I'd post it here.

Seems like it is possible to over-torque that flywheel nut.

And if you do, it can throw off the e-shaft end play.

Putting the engine back together, I tried the largest end-play spacer I could get and still couldn't keep the front counter-weight from contacting the needle-bearing that sits on the thrust plate when hand-tightening the hub bolt.

I must've put the front of the engine together 5 or 6 times.

When I finally decided to inspect the flywheel, I saw that there was an indentation where it contacts the rear gear. The indentation was just enough to screw up the end play.

A new (used, undamaged) flywheel fixed it.
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Old Jun 18, 2017 | 09:57 PM
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From: retired rotorist
that's why there's torque specs in the manual.
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Old Jun 18, 2017 | 10:23 PM
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Originally Posted by insightful
that's why there's torque specs in the manual.
Agreed.

..but the lack of the equipment to measure exactly 300 ft/lbs of torque is why most peeps under or overtorque that nut.
I wld be surprised if there are more than 5% of the rx7's on the road that are running the correct torque specs on that nut.
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Old Jun 18, 2017 | 11:11 PM
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well, to be honest, you must be using a huge *** 3/4 impact to be getting the flywheel on that tight. or putting oil/anti seize on the e-shaft and flywheel, allowing it to shimmey down over the taper.
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Old Jun 19, 2017 | 06:51 AM
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Originally Posted by insightful
well, to be honest, you must be using a huge *** 3/4 impact to be getting the flywheel on that tight. or putting oil/anti seize on the e-shaft and flywheel, allowing it to shimmey down over the taper.
No impact. Just a 3/4" breaker bar and a pipe extension. I'm 6'2", 230 lbs which is bigger than the average guy, but I didn't think big enough to apply enough torque to damage that flywheel.

And it didn't shimmy down over the taper, it was torque'd down too much and compressed the flywheel inside the flange. This shortened the length of the assembly just enough to cause end play problems on the front side.

I'm just putting this out there to let peeps know to be careful, because it can happen.
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Old Jun 19, 2017 | 08:12 PM
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Originally Posted by freq
No impact. Just a 3/4" breaker bar and a pipe extension. I'm 6'2", 230 lbs which is bigger than the average guy, but I didn't think big enough to apply enough torque to damage that flywheel.

And it didn't shimmy down over the taper, it was torque'd down too much and compressed the flywheel inside the flange. This shortened the length of the assembly just enough to cause end play problems on the front side.

I'm just putting this out there to let peeps know to be careful, because it can happen.
actually we do have the proper tools.

if the spec is 300 lbs/ft, you literally can apply 300lbs to a 1 foot bar.

or divide 230lbs/300 = 1.3, so 12" times 1.3, is 15.6"

so at 230lbs you can hang from a 15" bar and be torqued to spec.

i need a 2 foot bar..
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Old Jun 25, 2017 | 12:36 PM
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Originally Posted by j9fd3s
actually we do have the proper tools.

if the spec is 300 lbs/ft, you literally can apply 300lbs to a 1 foot bar.

or divide 230lbs/300 = 1.3, so 12" times 1.3, is 15.6"

so at 230lbs you can hang from a 15" bar and be torqued to spec.

i need a 2 foot bar..
Yep. Just have to add that for this to be the case, the bar has to be level to the ground. You could also use a pull scale at the end of a bar extension.
Another option altogether is a torque multiplier with a standard torque wrench.
This one is geared at 5:1, so you just set your torque wrench to 60 ft-lbs. Also good for loosening the nut if you don't have a decent impact gun.

https://www.amazon.com/gp/aw/d/B00IVT1S76/ref=mp_s_a_1_7?ie=UTF8&qid=1498411956&sr=8-7&pi=AC_SX236_SY340_QL65&keywords=torque+multiplie r&dpPl=1&dpID=51N5QLLAiwL&ref=plSrch
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