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Flywheel Video
Posted by: Early Guy ()
Date: November 19, 2020 05:55PM

I haven't been on the forum in quite a while. Just thought I would let all of you know that our club ( Chicagoland Corvair Enthusiasts) just posted a new bolted flywheel video on You Tube. I don't know how to do a link, but if you get on You Tube website and search Corvair Bolted Flywheel Process, it comes right up.the video was done in my garage. Larry and I did the demo and John Meyer did the video.


Ray Johnson Villa Park IL 63 Spyder Conv. 140 EFI

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Re: Flywheel Video
Posted by: wittsend ()
Date: November 19, 2020 06:25PM


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Re: Flywheel Video
Posted by: Early Guy ()
Date: November 19, 2020 06:42PM

Great thanks for posting the link.


Ray Johnson Villa Park IL 63 Spyder Conv. 140 EFI

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Re: Flywheel Video
Posted by: gwrench ()
Date: November 19, 2020 06:55PM

Thanks for the video! I learned quite a bit from it.

Dale
Loveland, Colorado

1965 Monza 140 barn find

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Re: Flywheel Video
Posted by: Beers ()
Date: November 19, 2020 08:20PM

Great video Ray.

Very informative and fun to watch. Thanks for posting.

63 Monza Spyder convertible [www.corvairforum.com]
SF Bay Area, CA

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Re: Flywheel Video
Posted by: toms73novass ()
Date: November 20, 2020 03:31AM

Nice Video!

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block (Sold)
86' BMW 325es
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo
67' UltraVan 211 "Violet"
NFCC, UMCC
Grand Island, NY

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Re: Flywheel Video
Posted by: vairmech ()
Date: November 20, 2020 05:01AM

There is only one thing I disagree with and that is drilling all of the holes individually. Well maybe 2 things, I also will not drill oversize holes as mentioned.

Well, 2 things. I did see the fixture for centering but my jig takes care of that, I'll post a pic later.
The big take away that was glaringly wrong is the flywheel is BOLT CIRCLE CENTERED! The OD of the flywheel has NOTHING to do with being true. This is stated in the blue prints very plainly.

Darn, 3 things! One last thing on the bell housing bolts. The washers used on the 5 bolts around the seal are not your standard thick washers but they are thinner than what you buy at the hardware store!

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Flywheel Video
Posted by: corventure Dave ()
Date: November 20, 2020 10:41AM

Great video. thumbs up I agree with Ken. But I will add a couple observations.
Button head bolts only clamp the 3 flywheel parts together. Where as tapered flat head bolts that are counter drill set into the backing plate and also slightly into the spring center plate give a greater hold for alignment. Also have better clearance from the outer bellhousing bolt heads.

The stepped flywheel with the recessed rivet holes was partly an attempt to resolve rivet loosening issues. The first flywheels in the early 1960 line up had 3/16 thick rivets that were changed to 1/4 rivets because of this issue.

Flutter alignment… That's referred to as Radial alignment. As edge alignment is referred to as Axial alignment.

Factory tolerances were up to .028! I agree with the video, .005 or less is best.

Over the years I have came across several bolted flywheels that were rebuilt by a popular supplier out West who retired from the business. Bolts can indeed loosen. So the myth that bolting never fails is a bit debunked in my experience.

Also, the rattling noise of a lose flywheel to me sounds mush like a rod knock. And as Larry said, it goes away when pushing on the clutch.
I bought several cheap Corvair's cheap in the 1980's because they had "bad rod bearings"!!! Nope it was the flywheel!

Not mentioned is why the factory rivets loosen.
From Bob Benzingers presentation, data and archival photos...
When the flywheels were originally built, all tree plates were aligned in a fixture and all 12 rivet holes were bored at the same time. The rivets were then pressed in "cold". Cold pressed rivets only bond from the swedged toe of the rivet with little clamping force. When we look at industrial rivets used in bridges, buildings and other construction... these are forged-hammered in place Red hot. The hammered hot rivet expands into the hole its driven into. Then hammered "forged" into place mushrooming the rivet toe. The hot rivet then cools and contracts length wise creating an extremely tight bond. Forged rivets were used for many years instead of bolts due to their secure bond and resistance to harmonics. A good example is suspension bridges.
So why did GM not use Hot forged rivets or even the bolts many are replacing them with today? Simply... cost!
The Red hot forged rivet method I have been using since 1976 has been working in well over a thousand Corvair flywheels over the years. I have yet to see a failure. Or at least none have been brought to my attention.
This is not to say forged rivets are better. Bolting was and is a basic rebuilding alternative practice for many years.
The most important thing to learn here is that the original Corvair flywheel can and will loosen and the advice Larry mentions is vary sound. If you have your standard trans engine out. It's a good time to change that OEM built flywheel.

smileys with beer

Corventure Dave



Edited 1 time(s). Last edit at 11/20/2020 10:42AM by corventure Dave.

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Re: Flywheel Video
Posted by: Willt65 ()
Date: November 20, 2020 11:39AM

Does mileage seem to be the ticket to loose rivets, or is it just age? My flywheel/engine only has 49K miles on it. Just wondering what experience says?


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Flywheel Video
Posted by: Wagon Master ()
Date: November 20, 2020 03:31PM

Mine is supposedly on it's way.

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Re: Flywheel Video
Posted by: vairmech ()
Date: November 20, 2020 03:51PM

Willt65 Wrote:
-------------------------------------------------------
> Does mileage seem to be the ticket to loose rivets, or is it just age? My flywheel/engine only has 49K miles on it. Just wondering what experience says?
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I have a 47,000 mile 64 that is still good. It really depends on how the car is used, I think.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Flywheel Video
Posted by: RobertC ()
Date: November 20, 2020 05:29PM

Willt65 Wrote:
-------------------------------------------------------
> Does mileage seem to be the ticket to loose rivets, or is it just age? My flywheel/engine only has 49K miles on it. Just wondering what experience says?

Replaced one at 68,000 miles, but bought the car at 52,000 miles - no clue if the flywheel was original.

Replaced that one at 126,000 miles.

Neither rattled.

Used bolted flywheels after that.

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Re: Flywheel Video
Posted by: nirvairna ()
Date: November 23, 2020 04:41AM

vairmech said: I did see the fixture for centering but my jig takes care of that, I'll post a pic later.


Ken, I would like to see the picture of your fixture jig

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Re: Flywheel Video
Posted by: vairmech ()
Date: November 23, 2020 05:22AM

nirvairna Wrote:
-------------------------------------------------------
Snip
>
> Ken, I would like to see the picture of your fixture jig

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I'll make a new post with multiple pics.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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