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HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 08, 2016 04:14PM

When mating a PG to the Diff there are shims that go on the diff pinion shaft that limit the Planet carrier hub thrust movement,This shim stack measurement is critical for proper PG trans operation,PGs 4-6 and 4-7 in the 65 shop manual goes over this procedure using J-Tool 8364, This posting will show you how to do this using a piece of flat stock and a digital caliper.

The running clearance for this measurement is .025 - .045 per the manual, this is the clearance needed between the shim stack and the planet hub carrier, So We need to figure out how many and what thickness shims are required to obtain this running clearance. so first We must find the Trans and Diff Clearances, Here is how to do this with a digital caliper.

First find a rigid piece of flat steel, in this case I am using a small 6 steel ruler and using it on edge so it will be rigid with no deflection when measuring.
measure the thickness of the flat stock as it will be needed for the math, in this case the measurement is .772 Write it down.

Next set your PG trans down on its back so the mating surface is straight up, With NO GASKET place the measured flat stock on edge across the mating surface spanning the center of the planet carrier hub,use the depth finder rod on the caliper to measure the depth of the planet carrier hub to the top of the flat stock on edge, Make sure you have everything in a straight line as to get a correct reading, also do this numerous times until you have a number that has repeated itself to rule out a false measurement, In this case the measurement is 1.778, Write that down,

Next take the flat stock and place it on the Diff mating surface WITH NO GASKET so it spans the pinion shaft and rest flat against the mating surface on edge,you might need to slide it slightly away from the center shaft as you need to make sure the flat stock is resting perfect on the mating gasket surface of the diff, using the depth Gauge rod again, measure the distance from the edge of the gear (With no Shims and gear slid towards the diff on the shaft until it stops) Rest the bottom of the caliper on the gear and the end of the depth rod on the flat edge of the flat stock, Once again making sure its in a straight as plain as possible and do it numerous times to get a accurate reading, Having a friend hold the flat stock in place is a great help, Take this measurement and write it down , In this case it is .240.

Now time to do math, Using the PG measurement of 1.778, We need to Now Subtract the Flat stock from the equation.

So 1.778 - .722 = 1.056 this is the depth of the planet carrier Hub from the mating surface.

Next we need to Add the flat stock to the Diff number.

So .240 + .722 = .962 This is the height of the gear edge from the diff mating surface.

Now we need to subtract the diff gear height from the PG planet carrier Hub depth to find our Clearance.

So 1.056 - .962 = .094 This is the running clearance between the Planet carrier Hub and the Governor gear on the pinion shaft, so now we need to select our shims to bring this number into the range outlined in the Shop manual .025 - .045

We want to try and get as close to the center IMO of the clearance range, the shims I have collected are all either .016 or .032 in thickness, So in this case if we use 2 .032 shims it will bring our final measurement to .030

.094 - .064 = .030 final running clearance, You can mix and match the shims as needed to get within the .025 - .045 range as outlined in the manual.
smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 08, 2016 04:16PM

smoking smiley

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 08, 2016 04:28PM

One more pic for clarification smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: GWLee ()
Date: August 08, 2016 04:50PM

Thank you Dave I'm going to save this. I will have to do this in fall and I've read but still didn't fully understood how. You have answered that for the original poster of this and myself.

Thanks so much.

Lee Adkins

A Cave Man car
1960 2dr Coupe with pg
Color Tasco Turq.
With Ermine white top.

Catlettsburg,
In the Beautiful state of
North/East KY!

Not the best pic, but the only I had from then, 1997!

2016!

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: MattNall ()
Date: August 08, 2016 05:10PM

In the Sticky it goes!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 08, 2016 05:20PM

Hope I did it right! lol drinking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




Sign my guest book!
[motoheadmall.com]
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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: MattNall ()
Date: August 08, 2016 05:30PM

"Someone" will let you know...if you are wrong!!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: Murphy ()
Date: August 08, 2016 05:57PM

Nice Job explaining this.thumbs up

65 Monza Coupe
61 500 Coupe (under Construction) Getting close.

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: MattNall ()
Date: August 08, 2016 05:59PM

You can also use clay with oil on the metal surfaces assemble without gasket and then measure it..





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 08, 2016 06:06PM

I advise against the clay, I found it a PITA and the results not very accurate, I tried the clay before doing it this way, and think this is much easier and more accurate, Also I do have the correct J - tool, but it is at the ranch and needed to figure this out now.





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




Sign my guest book!
[motoheadmall.com]
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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: moomba32 ()
Date: August 08, 2016 06:58PM

Outstanding!!!

Don Marlowe
66 Monza 2Dr 140/pg
64 Spyder convertible now, 110/pg
Eutawville SC

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: bought1 ()
Date: August 08, 2016 07:58PM

Yup that's how I have done it. Kudos to Dave for writing it up and posting pics!

Dave

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: veverlove ()
Date: August 08, 2016 11:01PM

I chime in with another "Thank you, Dave." thumbs up Also, a kudos on the engine cradle and getting it to me so quickly. Looking forward to getting the HF trans jack to connect it to. Perhaps even this week. I really need to get some transportation, again and your piece will really come in handy, being by myself and all.

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: 67 airvair ()
Date: August 09, 2016 07:54AM

I discovered a hole in your method of measuring, shown in pictures 4-5. I double-checked my diff to make sure I was right, as I knew there was a reason I was having trouble with that particular method.

Sure enough, the pinion shaft adjusting sleeve in my diff is cast unevenly, and machined and assembled in a manner that leaves half of it sticking ABOVE the diff carrier machined face. You simply cannot put a straightedge across it for half of its diameter.

This may be why the factory repair manual cautions you to be sure to measure to the machined diff carrier surface, and double check in several places to ensure a correct reading.

It's quite a stretch from the governor gear to the machined surface of the diff carrier, so I'd be cautious about how this depth is measured. You'd need add some shims under the straightedge so as to prevent it from coming into contact with the adjusting sleeve.

-Mark

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: bought1 ()
Date: August 09, 2016 08:04AM

Daves method works. I have used it twice with success. Perhaps you have a machining defect or you pinion adjuster sleeve is incorrectly installed. Just a thought...not a criticism...smiling smiley

Dave

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 09, 2016 08:17AM

Mark, move the straight edge to the lower area in the adjusting sleeve where the straight edge sits flat on the mating surface, I have found UN-Even castings just like yours and move the straight edge around until it sit's flat for the measurement, you can even use a piece of flat stock with feet on the ends or shims to bridge the adjusting sleeve if needed, I know there is no "Hole" in my method of measuring as I have double checked my Numbers with My J-Tool used in the shop manual and my numbers were the same. smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: 67 airvair ()
Date: August 09, 2016 08:29AM

I think we're on the same page, Dave. It's just that I expressed it differently.

I just wanted to caution everyone to be careful, should their adjusting sleeve be sticking up and they not catch it. Putting shim "feet" under the straightedge in the first place is the safest way of ensuring no inadvertent error is made.

It's similar to my using 1-2-3 blocks in what I was initially doing.

-Mark.

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: davemotohead ()
Date: August 09, 2016 08:31AM

Also Mark, I did this write up Just to help you! And your first post in this thread is trying to "Poke Holes" in the method Used to help those with no J-Tool , You Could at least have Thanked me for doing all this work just to help YOU instead of trying to find fault with this method, and then you could have added your concern about the UN-even adjusting sleeve, Sometimes I think you are a Chronic Complainer, and in that context of thought this is just for you: Dizzy, Turkey Roaster, Rear Windshield, Clarks Catalog! smoking smiley





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)




Sign my guest book!
[motoheadmall.com]
-----------------------------------
Rust Free Lancaster Ca

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: bought1 ()
Date: August 09, 2016 09:01AM

Mark can you post some pics?

Dave

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Re: HOW TO : Figure out the correct shim stack for a PG to Diff mating.
Posted by: Murphy ()
Date: August 09, 2016 10:29AM

I've been watching this subject because I'm in the process of mating a rebuilt differential and powerglide. I knew eventually if I read enough about it I'd get it into my thick skull.grinning smiley

Dave did a great job explaining everything, which I already gave him an "atta boy" for explaining it. If you bother to read what Bob Ballews wrote, you'd see how he overcame the uneven adjusting sleeve.

Reading how to in the shop manual isn't always clear, probably because it was written by an Engineer.tongue sticking out smiley

Again, thanks Dave for helping me too.

Remember, some people would complain if you were to hang them with a NEW rope.eye rolling smiley

65 Monza Coupe
61 500 Coupe (under Construction) Getting close.

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