My 1971 521

[Crashtd420]

5 minutes ago, d.p said:

I can disconnect the lines/parking brake I guess. Got a part number for that seal? 

I'm sure I do some where.... just replaced them last winter....

 

[Crashtd420]

Found this ...

Trying to find my info...

Your after the inner seal..

[datzenmike]

1 hour ago, thisismatt said:

I feel like 3.7 is a good compromise. When I had my 510 and paid more attention to that scene it seemed like 3.7 was a sought after ratio and 3.54 was a little too high, at least for the guys doing 4 cylinder swaps, SR20DE/T for instance.

 

510 is lighter. DP's 3.70 will 'feel' like a 3.889 with those tires. I like where this is going and should serve you well on the highway.

[wayno]

I am a great believer in don't fix what is not broke, I have never had a rear axle seal leak in 25 years of Datsun ownership myself and I have had a bunch of Datsuns, you can start messing with changing things and if you do not fully understand what you are doing it could start leaking because you did not do the installation right and then you will have to pull that side apart again to try and get it right.

 

As far as getting the axle out far enough to remove/replace the drop out gears I have always been able to pull it out just far enough without having to remove the clip holding the e-brake cable on the frame, but it has been a while since I worked on a 320/520/521 frame, I have always had to either loosen or cut the e-brake cable when at a wrecking yard to remove drop outs from 720 trucks or hardbodies to make it easy as I was by myself, I think I disconnected the center pull on my 521 work truck to change out rear gears, but that was a long time ago as I have had a dually axle under the work truck close to 15/20 years now.

[Stoffregen Motorsports]

14 hours ago, wayno said:

I am a great believer in don't fix what is not broke, I have never had a rear axle seal leak in 25 years of Datsun ownership myself and I have had a bunch of Datsuns, you can start messing with changing things and if you do not fully understand what you are doing it could start leaking because you did not do the installation right and then you will have to pull that side apart again to try and get it right.

I'm with you Wayno, but I expect you and I think that way because of the amount of vehicles we each own. I can hardly keep up with keeping the batteries charged let alone restoring each and every car, truck, tractor or motorcycle I own.

 

A lot of these guys here want to replace the parts in their cars and trucks as a matter of course, in an effort to restore them - making everything new, regardless. I get that. Hell, that's how I make my living. So telling them to leave it alone - you're pissing in the wind.

[wayno]

I expect your right, the rear axle seal is not a high wear item that starts leaking every 100,000 miles, they last the life of the vehicle most the time, I guess I just don't have the need to work on my trucks all the time by replacing everything weather it needs it or not, it cost money and the new parts out there are crap, made in China crap, that work like shit/crap.

 

We do have the same issue with batteries. :lol:

 

 

1 hour ago, Stoffregen Motorsports said:

I'm with you Wayno, but I expect you and I think that way because of the amount of vehicles we each own. I can hardly keep up with keeping the batteries charged let alone restoring each and every car, truck, tractor or motorcycle I own.

 

A lot of these guys here want to replace the parts in their cars and trucks as a matter of course, in an effort to restore them - making everything new, regardless. I get that. Hell, that's how I make my living. So telling them to leave it alone - you're pissing in the wind.

 

[bilzbobaggins]

Ive got a 2012 titan I am trying to find a rear end for myself.  Lost an axle seal going down I20.  Then we heard the tell tell sound.  I do a once over on all my vehicles when changing the oil.  Never had any signs of weeping or leakage.  That was a year ago.  Those seals lasted 300,000 miles.  Id almost bet its a damned if you do, damned if you dont situation on changing his.  I am just adding this to the conversation, not picking a fight or talking shit.  

[mainer311]

22 minutes ago, bilzbobaggins said:

Ive got a 2012 titan I am trying to find a rear end for myself.  Lost an axle seal going down I20.  Then we heard the tell tell sound.  I do a once over on all my vehicles when changing the oil.  Never had any signs of weeping or leakage.  That was a year ago.  Those seals lasted 300,000 miles.  Id almost bet its a damned if you do, damned if you dont situation on changing his.  I am just adding this to the conversation, not picking a fight or talking shit.  

M226? I’ve replaced like 6 of those seals. The early axles used to corrode and wear the seals out in no time. There’s no grease in the M226 outer bearings. They’re lubricated by the oil in the diff that travels down the housing tubes. Usually you get gear oil all over the inside of the rim once the seal starts leaking.

[bilzbobaggins]

7 minutes ago, mainer311 said:

M226? I’ve replaced like 6 of those seals. The early axles used to corrode and wear the seals out in no time. There’s no grease in the M226 outer bearings. They’re lubricated by the oil in the diff that travels down the housing tubes. Usually you get gear oil all over the inside of the rim once the seal starts leaking.

 

Beats me, no point in replacing the seals now.  Rear end sings and pinion gears were like floppy dicks when I opened it up.  We ended up with all kinds of gear oil after on the wheel after it failed.  I have just been looking for a deal on another rear end.  And I know the damn thing was dry bc I put parking brake shoes on it the month before it crapped out.

[wayno]

The 3.7 gears are on the way, I cannot stress enough that you will need to clean the unit out completely, bearings/everything as they have paint/bondo dust in them, you do not have to pull it apart, it just needs to be cleaned out with something that will not destroy the front seal, I will not say what I use.

 

Personally I would just take it apart like I described in an earlier post, pull the drum/axle out around 4 or 5 inches(that is about all it will pull out) and change out the drop outs, make sure you clean the mating surfaces, especially if the stock seal/gasket comes apart, I have made gaskets to replace the original ones that were ruined when pulling the drop out, I used large cereal boxes or oil pan gasket containers like in the photo below, you can see the gasket I made below has a fold in it, I never used this one because of the fold as the cereal box was not a large box, you need to use a large box without any folds as I have lost a set of gears because of the fold, I suppose you could use large amounts of gasket maker but if it leaks you have to pull everything apart and fix it, normally I use these gaskets I make dry and except for that one time the one had a fold I have had no issues.

 

[Crashtd420]

Hey dp if you like the new gears I'd be interested in the 4.37 gears if you wanna get rid of it...

Just keep me in mind...

[d.p]

Thanks @wayno I have a brand new rear diff gasket already so I don't need to make one.  I had planned on changing that gasket when I swapped the drive train but never got around to it.   Can I just blow it out with compressed air?  Not sure what to use other than air and or simple green/purple power?   

 

 @Crashtd420 for sure I can't imagine I would have any use for them after the fact if all goes well so they are yours if it all works out.  

[mainer311]

1 hour ago, d.p said:

Thanks @wayno I have a brand new rear diff gasket already so I don't need to make one.  I had planned on changing that gasket when I swapped the drive train but never got around to it.   Can I just blow it out with compressed air?  Not sure what to use other than air and or simple green/purple power?   

 

 @Crashtd420 for sure I can't imagine I would have any use for them after the fact if all goes well so they are yours if it all works out.  

Gasoline. Mineral spirits. If it were me, I’d tear it down and flush everything out or replace all bearings. Don’t touch it with water. You want something that will just flash off like gasoline.

Edited February 9, 2022 by mainer311

[wayno]

😄 I used compressed air before taking the photos as it looked way worse, gear oil attracts dirt and that is why I bag them, but dust floating around in the air in the garage with the garage door closed gets in everything, bags that are not quite big enough does not help, and I bagged them long ago, but the sanding happened recently, things get moved, bags get opened by accident or just come open while using an air blower to blow out the garage of dust the bags flap and stay open, everything in my garage has dust on it, thick dust on the gearsets because of the sticky gear oil.

 

[wayno]

11 minutes ago, mainer311 said:

Gasoline. Mineral spirits. If it were me, I’d tear it down and flush everything out or replace all bearings. Don’t touch it with water. You want something that will just flash off like gasoline.

 

This gearset is tight, maybe a 1/16th inch play in the flange, it is what I looked for when I was pulling them in wrecking yards and selling them to 320 owners with 320m side gears in them, I never had a complaint, I think it will be fine if cleaned out, the only thing different is that this one sat for years in my garage.

 

Will gas hurt the seal in the front?

 

[mainer311]

Not likely. It’s probably seen conventional gear oil for 30+ years. Some quick contact with gas won’t do anything. 
 

And like I said, if it were me, I’d pull it apart and replace it anyway.

[d.p]

How tf do I know what bearings I need to order to replace?  I mean I don’t even know what vehicle this came out of?  

[mainer311]

Rock Auto lists bearings for H190’s. You need 2 of the same carrier bearings, and 1 inner and 1 outer for the pinion, along with the pinion seal. 

Edited February 9, 2022 by mainer311

[d.p]

2 minutes ago, mainer311 said:

Rock Auto lists bearings for H190’s. You need 2 of the same carrier bearings, and 1 inner and 1 outer for the pinion, along with the pinion seal. 

 
These mamma jamma’s?

 

https://www.rockauto.com/en/catalog/nissan,1986,d21+pickup,2.4l+l4,1210835,drivetrain,differential+pinion+bearing,2264

[mainer311]

Yeah. I picked a 620 from the mid 70’s and it looks like the part numbers are the same.

[datzenmike]

You will need the pinion to ring gear clearances checked if you do replace any bearings.

 

1 hour ago, wayno said:

 

This gearset is tight, maybe a 1/16th inch play in the flange, it is what I looked for when I was pulling them in wrecking yards and selling them to 320 owners with 320m side gears in them, I never had a complaint, I think it will be fine if cleaned out, the only thing different is that this one sat for years in my garage.

 

 

 

 

If any of the bearings are bad it will growl like a bear. Don't fix what ain't broken.

[mainer311]

13 minutes ago, datzenmike said:

You will need the pinion to ring gear clearances checked if you do replace any bearings.

 

 

If any of the bearings are bad it will growl like a bear. Don't fix what ain't broken.

Wayno said they’re full of dust…

[datzenmike]

Rinse them out with a gallon of gas while spinning the pinion. Let drip dry and pour a liter of ATF and spin the pinion to coat everything and displace any gas. Let drip dry for a day. The bearings in there will be better Jap quality than any crap you can replace them with.  

[mainer311]

I had the same idea, but if the dust is stuck in those rollers and caked with old gear oil, well, who knows.

[d.p]

I’ll take some pics when it shows up and see what’s doing.