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Yes there should be a tube pressed in that hole that sticks out the bottom of the block at the pan rail.
 

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Lower dipstick guide tube....keeps the dipstick from curling into the crankshaft, leave it out and the tip of the stick will get repeatedly hit and typically breaks off right at the "add" line imprint.
If you search, you can probably find a better price,
It's an odd diameter....3/8" hard fuel line won't fit, 5/16" will fit but is sloppy in the hole, it can be used in a pinch if you have to make your own since the upper stick tube traps it in place.



Machine shop didn't give it back to you?
 

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Discussion Starter #345
Lower dipstick guide tube....keeps the dipstick from curling into the crankshaft, leave it out and the tip of the stick will get repeatedly hit and typically breaks off right at the "add" line imprint.
If you search, you can probably find a better price,
It's an odd diameter....3/8" hard fuel line won't fit, 5/16" will fit but is sloppy in the hole, it can be used in a pinch if you have to make your own since the upper stick tube traps it in place.



Machine shop didn't give it back to you?
No. But honestly I didn't see one during the tear down so maybe it wasn't ever there.
 

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Discussion Starter #346
Picking this up today. I'm really nervous about doing this lol. I don't know why.
409852
 

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Discussion Starter #347
$275 Is this worth it? Description reads

"3.73 posi 30 spline center chunk. Like new. 275 obo negotiators welcome, possible barter/trade. Make an offer"

409853
 

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All the 8.5" 10-bolts have a 30 spline pinion stem, but what you really need to know is if the axle spline in the posi is 28 or 30....28 is stock in the 8.5" Nova rear, 30 spline didn't arrives until 1988, and while it can be retro-fitted to the earlier rear it requires you to replace the axles with aftermarket 30 spline units so the spline count matches.
Add reads like it is 30 spline chunk, so it would not work without replacing the axles....but you might want to confirm the seller actually knows what spline to count, he may have just counted the pinion spline.

You'd also want to find out if you can what brand it is, so you know what type clutches it has and whether it could be rebuilt if needed. ...Cone clutch Auburn differentialss can't be rebuilt.

it wold be worth it if the spline matches....but i have a suspicion it is out of a late model truck, so it would be 30 spline.
 

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Discussion Starter #349
All the 8.5" 10-bolts have a 30 spline pinion stem, but what you really need to know is if the axle spline in the posi is 28 or 30....28 is stock in the 8.5" Nova rear, 30 spline didn't arrives until 1988, and while it can be retro-fitted to the earlier rear it requires you to replace the axles with aftermarket 30 spline units so the spline count matches.
Add reads like it is 30 spline chunk, so it would not work without replacing the axles....but you might want to confirm the seller actually knows what spline to count, he may have just counted the pinion spline.

You'd also want to find out if you can what brand it is, so you know what type clutches it has and whether it could be rebuilt if needed. ...Cone clutch Auburn differentialss can't be rebuilt.

it wold be worth it if the spline matches....but i have a suspicion it is out of a late model truck, so it would be 30 spline.
He said it's from a 70s Camaro.
 

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I just noticed...it is a 12-bolt chunk...not a 10-bolt.

Look close, two ring gear bolts in every rib divided section, you can see 10 bolts in the pic and there are obviously 2 hidden from view by the bearing .

12-bolt are 30 spline axle and 30 spline pinion.

No go in a 10-bolt housing.

Any stock 8.5" 10-bolt posi unit from the 1970's will be an Eaton clutch style, and have a flat wave preload spring in the center, not the two seperate plates and multiple coil spring preload pack like the 12-bolt and the auburn diffs have

Looks like this:

409863


409864
 

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Discussion Starter #351
I just noticed...it is a 12-bolt chunk...not a 10-bolt.

Look close, two ring gear bolts in every rib divided section, you can see 10 bolts in the pic and there are obviously 2 hidden from view by the bearing .

12-bolt are 30 spline axle and 30 spline pinion.

No go in a 10-bolt housing.

Any stock 8.5" 10-bolt posi unit from the 1970's will be an Eaton clutch style, and have a flat wave preload spring in the center, not the two seperate plates and multiple coil spring preload pack like the 12-bolt and the auburn diffs have

Looks like this:

View attachment 409863

View attachment 409864
Impressive!
 

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Discussion Starter #352 (Edited)
Ok so here we go! I'm starting after work today. The first thing I need to do when degreeing a cam is find real tdc correct?

What are the next things. I wanna know so I can do a little research during the day.
 

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Yes, true TDC is first, to correctly zero degree wheel.
Then set up dial indicator to read off either the lifter or the pushrod tip for cylinder #1 intake valve( 2nd lifter bore back from drivers front corner), then rotate crankshaft until the lifter is on the cam base circle.
Then zero the indicator and you are set to start taking readings off of lifter rise..

I typically use intake opening and closing points @.050" off the cam card, rather than lobe centerline method. The intake closing point is the most important of the 4 open/close events to get correctly timed to the crank.
 

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Discussion Starter #354
So how's the best way to move this crank and adjust the wheel.
409961
409962


I keep having to loosen the crank bolt to spin the wheel and it comes out of tdc. I noticed that a 32m socket fits over the actual crankshaft with the key. But then I can't mount the wheel.

I'm almost thinking about making something like this.
409963
 

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I use a short bolt and a star washer so it bites into the wheel so it cant spin. It takes a few tries but when you go for tdc with the piston stop you can see how many degrees to one side you are. Then split the difference and try to make one move of the wheel and tighten it down.
 

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Discussion Starter #356
I made this really quick. Works as it should. I put a piece of conduit on it when when I want leverage and accuracy.
409970
 

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I've done the same with a big crescent wrench, tightened down close the key prevents it from slipping. Now I've got a large machinery nut off a 1.250 bolt with a key way hand filed inside it, works pretty much just the same as your cut socket tool when used with the big crescent wrench.
 

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Discussion Starter #358
Ok. Find tdc. And the pointer is actually touching the wheel so there isn't any visual nonsense.
409971
409972
 

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Discussion Starter #359 (Edited)
Ok I've been procrastinating degreeing my cam cause I don't know what the F im doing and I'm intimidated. Can you guys help me through it. I need help.

I've watched over 10 videos but they all seem to be different.
 

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Discussion Starter #360
So this is my current set up. I am into there travel of the indicator just a smidge. Am I cool to proceed?
410528

410530
 
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