Ok Nick,
I've taken the old girl for a drive since. I removed my 600mm long resonator because that just dropped the sound down too low for my liking.
It really hasn't changed the loudness of the exhaust. I braced it off the gearbox mount and I think that might have cause a bit of additional cabin sound. But it actually sounds really nice now. Almost has a throaty growl to it. Still sounds like an SR, but sounds better than it did.
No difference to the resonance that was annoying me.
But I'll revisit this project when I can be bothered at a later date!
Attachment:
20160730_131257.jpg [ 1.8 MiB | Viewed 5985 times ]
For now I've been focusing on my Diff.
This is the helical diff centre with the top cap off to inspect the gears and make sure they're all good.
Attachment:
File comment: The inside Helical Gears
20160812_094701.jpg [ 1.17 MiB | Viewed 5985 times ]
This is the helical gearset for those who have not seen one before:
Attachment:
20160812_204712.jpg [ 1.3 MiB | Viewed 5985 times ]
I asked my mate really nicely (who's got access to a metal lathe) to make up some bushings for me:
Attachment:
20160813_101124.jpg [ 838.88 KiB | Viewed 5985 times ]
They're within .01mm tolerance to what I want. They sat pretty perfect.
That allowed me to bolt my 10mm crownwheel onto my 12mm centre.
Now I discovered when I was pulling the centre out and inspecting it, that the guy before me had taken the pinion flange off already, so I had lost the pre-load on the pinion bearing.
I pressed out the pinion gear and cleaned up and inspected the bearing. It seems ok, but I've reinstalled it with a new oil seal and it's not spinning that great
Now i've got a Pinion bearing from the S15 donor diff that i'm considering pressing off and installing onto the long nose one, In fact i think I might do that because the side bearings on the old centre were shagged, so the pinion bearing is probably gone also.
Workshop manual says torque the pinion flange on to 137-159 ft-lb. Mine is obviously a used bearing, so i've torqued it up to about 130 ft-lb to try and "guess" the correct pinion pre-load taking into consideration the wear it would have had.
Then I installed the centre back into the housing.
I have two sets of shims, so i played around (these bearings have plenty of pre-load), and the best I could come up with on my dial indicator for back-lash is 0.4mm.
Fair way away from the 0.10 - 0.15mm that is Nissan's acceptable tolerance.
I haven't put any paste on yet to see the wipe pattern, but i don't know if I can get it much better because I don't have enough shims. It could be that the Pinion is sitting too low or high relative to the crown wheel, so all these variables are going through my head and i've got limited tools to address it.
I don't like doing it, but I might have to take it to someone to set it up for me
_________________
Ongoing Project: 1972 Datsun 510 S13 SR20Det.
http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18