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PG Flex Plate bolts
Posted by: kingmakeraz ()
Date: February 26, 2018 06:32PM

Question....
Do the 6 bolts holding the flex plate to the crankshaft get lock washers?
What is the torque spec?

Here is a picture of how I found mine on my 1965 Monza Coupe.

Cheers,
David

------------------
kingmakeraz
Mesa, AZ
65 Monza Coupe
65 Monza Convertible

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Re: PG Flex Plate bolts
Posted by: JimBrandberg ()
Date: February 26, 2018 07:12PM

No washers. I use blue Loctite on them, others seem to prefer a sealer.

Jim Brandberg
Isanti, MN
CorvairRepair.com

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Re: PG Flex Plate bolts
Posted by: WalterElias ()
Date: February 26, 2018 07:20PM

As Jim said clean the threads and apply a sealant or loctite. The other end of the bolt is exposed to the inside of the crankcase and splashing, hot oil. The torque specs are 20-26 ft lb. I like to also put a little sealant between the flex plate and crankshaft in case the key way leaks or the seal between the crankgear and the crankshaft not optimum.

Dan Kling
1961 Greenbrier Deluxe, 110 HP, 4spd, 3.89 stump puller
1963 Spyder Coupe, restored, converted to 4spd Saginaw
1967 UltraVan #299, The migration has begun, we're on the road again......Save the Whales!

Photos of our Greenbrier, UltraVan and work-in-progress @

[www.flickr.com]

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Re: PG Flex Plate bolts
Posted by: Frank DuVal ()
Date: February 26, 2018 09:19PM

They were that loose? Wow.

Sealant + torque wrench is all I have used.

Frank DuVal

Fredericksburg, VA

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Re: PG Flex Plate bolts
Posted by: JimBrandberg ()
Date: February 27, 2018 04:39AM

WalterElias brings up the torque value for those bolts and there's something that bothers me, the ones for flywheel anyway.

The 61 Service Manual calls for 20something and the 65 Service Manual calls for 40something when tightening those bolts. I've been splitting the difference at 35, any more seems excessive for a 11/32 bolt. What are other folks doing?

I've heard of other folks with loose flex plate bolts.

I've got flex plates laying around so I just replace them when the bolt surfaces are chewed up from the bolt heads tightening directly against them. I suppose GM didn't figure they would be removed and replaced very often during a normal vehicle lifespan.

Jim Brandberg
Isanti, MN
CorvairRepair.com

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Re: PG Flex Plate bolts
Posted by: azdave ()
Date: February 27, 2018 06:36AM

I would use only the bolts like from the factory.

You can see some engine oil was seeping past the bolt threads and getting flung off the flex plate. Clean the bolt threads and the bolt holes. Use blue Loctite and torque to 25#ft max. Make sure the flexplate and bolts were not damaged by the failure.

Be sure to install the flex plate with the concave side towards the engine so as you tighten the three flexplate to TQ bolts, it pulls the flexplate into contact with the TQ.


Dave W. / Gilbert Arizona
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
65 Monza 455 Toro V8
65 Monza 110 Convertible
65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed




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Re: PG Flex Plate bolts
Posted by: JimBrandberg ()
Date: February 27, 2018 06:47AM

You say 25# max. Do you think the value in the 65 Service Manual was an error?

Jim Brandberg
Isanti, MN
CorvairRepair.com

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Re: PG Flex Plate bolts
Posted by: azdave ()
Date: February 27, 2018 07:04AM

JimBrandberg Wrote:
-------------------------------------------------------
> You say 25# max. Do you think the value in the 65
> Service Manual was an error?


The manual I saw shows a range of 20-26 when sealer is used on the threads. With the loctite or sealer acting as a lube that seems logical to me. I'm far from PG flexplate expert.


Dave W. / Gilbert Arizona
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
65 Monza 455 Toro V8
65 Monza 110 Convertible
65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed




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Re: PG Flex Plate bolts
Posted by: 66vairman ()
Date: February 27, 2018 09:34AM

This is interesting.

The 65 manual says 40-50 ft. lbs. for the manual flywheel and 20-30 ft. lbs. for the PG flexplate. The range reflects lubed or dry threads.

In 66 the manual says 45 ft. lbs. for the manual flywheel and 25 ft. lbs. for the PG flexplate.

The grade 8 bolts are the same diameter and pitch 11/32-24, but are different lengths (flywheel thicker than flex plate).

A general torque chart says grade 8, 11/32-24 is 35 - 44 ft. lbs.

I'm going to guess the flexplate bolts are torqued to a lower value to prevent fracturing of the flex plate around the bolt holes. This was an issue with the big engine 57-58 Lincoln and Edsel flex plates.



Edited 2 time(s). Last edit at 02/27/2018 09:36AM by 66vairman.

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Re: PG Flex Plate bolts
Posted by: azdave ()
Date: February 27, 2018 10:23AM

Things sure were simpler when I was young and didn't own a torque wrench. smiling smiley


Dave W. / Gilbert Arizona
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
65 Monza 455 Toro V8
65 Monza 110 Convertible
65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed




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Re: PG Flex Plate bolts
Posted by: MattNall ()
Date: February 27, 2018 10:26AM

For sure!! ggg





MODERATOR
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Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: PG Flex Plate bolts
Posted by: Frank DuVal ()
Date: February 27, 2018 03:17PM

So that bolt would need two grunts!

Frank DuVal

Fredericksburg, VA

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Re: PG Flex Plate bolts
Posted by: joelsplace ()
Date: February 27, 2018 03:54PM

The line radiating out from the top right bolt looks like a crack in the picture. ???

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Re: PG Flex Plate bolts
Posted by: JimBrandberg ()
Date: March 02, 2018 07:55AM

So you guys are comfortable torquing flywheel bolts to 44 #s? It seems like a lot to my sensibilities.

Jim Brandberg
Isanti, MN
CorvairRepair.com

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