1970 s2 0453R Reassembly

[jbcollier]

Prussian blue isn't supposed to be dry.  Apply it to the teeth and apply pressure to the ring gear with the palm of your hand as you turn the pinion via the output shaft (lock one of them).  The bluing provides the "canvas" for the tooth contact pattern.  In other words, the tooth is blue except where the two teeth contact.  This is why you need to maintain some resistance to turning as you make the pattern.

You need to test the drive and coast patterns so you can determine what needs adjustment.  There are some combinations of patterns that are not correctable and indicate the gearset is worn out.

[dakazman]

  I did see a video on pushing against the differential. Here is a picture of the initial coating without pressing.
Dakazman

[BDA]

There is a yellow gear marking compound you might want to find. Amazon has it but I bet you can find it locally. I didn’t use it but since it is for this purpose, it should work well.

Using a Sharpie worked ok for me. Whatever you use, in order to get the best pattern, make sure your gears are FIRMLY meshing.

I’ll remind you to see if you need to worry about pinion depth. Some Renault trannies have adjustable pinion depth and some (like the NG3, thankfully) don’t.

[BDA]

Just found this that might be interesting: https://www.pirate4x4.com/threads/gear-marking-compound-alternatives.955158/

[dakazman]

  Yes this does have a pinion adjustment , or such in the manual however that was not touched. I’m keeping it simple. The advice JB mentioned gave on proper turning most likely will help . I was turning the primary shaft with the gearbox in gear . I put the clutch disc on it to really spin it.
    BDA, (nice link) I can’t imagine you as a pirate,    I have white lithium grease , white paint, I’ll even try the sharpie, and with all my girls around they might be able to find some lipstick.
  Plan B in the works  , I purchased another 336 gearbox for insurance. 😃

Dakazman

[BDA]

Funny you mention lipstick. MANY years ago, I remember reading an article about sportsmanship at the SCCA Runoffs and one guy helped setup a rear end with lipstick late at night because there was nothing else. IIRC, it worked for the race at least!

You’re right, I’m no pirate! Alas, I lost my parrot (https://www.youtube.com/watch?v=vZw35VUBdzo).

[Sandyman]

Let me guess. Your favourite Gear is "ARRR"

[dakazman]

   ARRR-right then, going back to serious side, this is what my pattern looks like now . I’m reading it as to far in and the differential side needs to loosened and the other side tightened one nut flange at a time to put the pattern more in center?
  I’ll stand down until I get confirmation on that..

  JB is correct again, locking down one output shaft and turning the other is a much better way to turn the ring and pinion. Also much easier when you have a spare drive yoke .
Dakazman

[jbcollier]

It's hard to say for sure from pictures.

In the first two, does the pattern go right to the root (bottom) of the tooth?

Is it also going off the heel (outer edge) of the tooth?

The bottom photos definitely show it going right to the toe (inner edge).

What's your backlash reading?

[jbcollier]

https://www.canadawideparts.com/downloads/dana_tooth_pattern.pdf

[jbcollier]

I like my contact areas to be central on the tooth between the top and the root but a slight bias towards the toe as high loads will cause the contact area to move a bit toward the heel.

[dakazman]

  Its definitely on top toe,(Pic 2) (per chart  towards center of ring.) Heel being the outer side.     

  I'm using the dana chart, face milling ( pic 1). Backlash now at .005-.006

   I cleaned gears again and now you can see a better transfer of the prussian blue. Coast side of gear is perfect (pic 3)

dakazman

[jbcollier]

To me the coast pattern shows a little too much toward the toe.  I can't see a discernible drive pattern.  Bear in mind you're looking at the real thing and I'm interpreting a photo.  A clearer photo of the drive pattern would be helpful for me.

[dakazman]

  JB , Still working on the gearbox and will have some more pics soon. I’m finalizing some details on another gearbox and should have that one as a guide to compare the readings and feel .
 Crossflow update:?
  My order for the extended M10 came in and I quickly cleared the last block head bolt hole. Now, as you stated the M12 holes need to be tapped out. That extended bit is on its way. I don’t have a clue why this M10 helicoil was down there. I removed all the M12 7/16 dia bolts and kept in order. The debris , old threads could have been from stacked helicoil inserts. See pics.
  Another milestone this week was unrelated to the Europa, the weather broke for a day with temps in the 70s’ . I was able to set final adjustments to my valves on the corvette motor. Sweat and oil on your glasses is never a good time to do anything.  a Zz4 crate motor that has been a nightmare since I purchased it during the GM restructuring.  It now is better than new and a nice ride around town.😅
Dakazman

 
 

[jbcollier]

That's not a helicoil.  That's thread that has broken away.