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Crashtd420

A 521 in Massachusetts

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Wow, nice find! That bearing is toast! Most bearings fail by means of spalling. A shattered one like that is odd, but either way, great due diligence.

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Not only fucked, but the balls are extremely pitted. Visually check the front counter and the rear counter that's supported in the rear case. Not only should they turn smoothly but they should be blemish free. If these are bad the other's might be as well.

 

These three bearings carry the full engine load in every gear except 4th. When under load the transmission tries to spread apart the counter shaft from the mainshaft above it. This is why transmissions are often quieter in 4th gear.

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48 minutes ago, datzenmike said:

Not only fucked, but the balls are extremely pitted. Visually check the front counter and the rear counter that's supported in the rear case. Not only should they turn smoothly but they should be blemish free. If these are bad the other's might be as well.

 

These three bearings carry the full engine load in every gear except 4th. When under load the transmission tries to spread apart the counter shaft from the mainshaft above it. This is why transmissions are often quieter in 4th gear.

Well 1 is already the new one for the front case..... 

I'm definitely going to check eveything tomorrow much easier to put new stuff in now if its needed......

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1 hour ago, mainer311 said:

Wow, nice find! That bearing is toast! Most bearings fail by means of spalling. A shattered one like that is odd, but either way, great due diligence.

I knew something wasn't right when I was tightening the nut......

I wanted to ignore it but I couldn't, it was more work than I anticipated but it wasn't as bad as I expected..... 

Its wierd it's like there was half a rebuild done to the transmission.... some stuff seems newer, it was definitely opened and resealed,  yet they left that bearing.... I could see how it could have been missed, even with both cases off I didnt realize it till it with almost to late....

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I almost think the counter bearing died once before..... I remember the inside of the front cover looked a bit odd.....

 

Screenshot-20181230-201546-Gallery.jpg

 

Not like it matters but it would make sense.... 

Edited by Crashtd420
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That was the cover from the old case...

For comparison this is the one I'm using on the L case....

 

Screenshot-20181230-201649-Gallery.jpg

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I saw that. Yeah looks like the counter bearing was destroyed. It was probably changed but the others never were.

 

I drained a transmission once and the balls fell out. The oil was white-ish silver gray like thick silver paint

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Just now, datzenmike said:

I saw that. Yeah looks like the counter bearing was destroyed. It was probably changed but the others never were.

That's what I'm thinking.... 

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When you see something like that you know the front lower bearing  destroyed itself, most the time when a front cover looks like that a bearing comes out of the front cover/punches a hole thru the front cover and ruins it, one time my bearing went the other way in the work truck and went thru/between the teeth of the closest gear and the countershaft/cluster gear shaft busted the end of the countershaft/cluster gear off at the bearing right next to it, I had no more reverse or fifth gear anymore, that transmission was destroyed and not worth fixing, but I used that 5th gear a couple months ago when for some unknown reason 5th gear lost 3 teeth in the current transmission, that messed up tranny is a parts transmission, the only thing it is good for after a vearing went thru the teeth.

I look at that big bearing front cover and say it is good that you are not going to use that cover anymore, what did that bearing hole in that case look like?

Edited by wayno

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Oh I forgot to show this.....

So there's one bearing that's about 7 inches down the main shaft I need to remove... 

Well the puller I rented wasn't even close to long enough.....

So I was able to use some 6" pieces of metal. I had to drill some holes and make some longer arms.....

 

20181230-130923.jpg

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2 minutes ago, wayno said:

I look at that big bearing front cover and say it is good that you are not going to use that cover anymore, what did that bearing hole in that case look like?

It actually looked good.. unfortunately this is the first transmission I've even really opened up so I didn't really know what I'm looking at, for me it's kind of hindsight now.... I guess I'm just glad I found it.... atleast I can fix it before a catastrophic failure.... I now I know exactly what condition the transmission is in.... 

 

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Dont reuse a bearing you've pulled by the free race. But you may have already known that.

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Just now, thisismatt said:

Dont reuse a bearing you've pulled by the free race. But you may have already known that.

Nope...... I did not.....

I probably gonna just replace them all and be done with it....

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So it looks like I have 4 bearings I'm gonna replace now.., couple are a little crunchy rolling around, one seemed good, but it took alot to get that one off so I'm not gonna risk it... I'm just gonna replace them all.. luckily the center bearing on the main shaft is good, I dont have to get that one out.... plus I already replaced the front bearing on the 5th/ reverse shaft.....  I'll try to get those order asap and i can get to reassembling. 

 

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Like I said, that bearing is a common failure point. I wouldn't be surprised to find that all of the rest of them were fine.

 

Glad you caught it. Would have sucked to find out after you installed it in your truck.

 

BTW - aren't you supposed to be resting?

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9 minutes ago, Crashtd420 said:

 couple are a little crunchy rolling around,

 

 

That right there is reason enough.

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1 minute ago, Stoffregen Motorsports said:

 

BTW - aren't you supposed to be resting?

I have been, I haven't been lifting or over doing it., been using air tools and friends to my advantage, plus only working in short intervals.. I've just been putting around the garage and house, but after about 6 weeks now I'm really really bored..... about 10 more days and back to work....

 

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Keep moving as much as you can but listen to your body. Mental boredom can't be good for the healing process. If you have to stop moving, don't stop dreaming. Visualize what you want to do. Exercise your brain.

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20 minutes ago, datzenmike said:

Keep moving as much as you can but listen to your body. Mental boredom can't be good for the healing process. If you have to stop moving, don't stop dreaming. Visualize what you want to do. Exercise your brain.

All exercising my brain is doing is making me want to spend more money I dont have right now..... 

Luckily the healing has been going good.... getting some small tasks accomplished on the datsun has been helpfull....

When I'm use to 10hr work shifts 5 or 6 days a week while working on the datsun,  this is a welcome break, even if I cant do to much.... an 8hour work day even feels like a vacation....

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Congrats on getting better health wise and Datsun wise!

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So I have 4 bearings I wanna replace, and I question the ones that were in it...

My main question is 2 of the bearings had a c3 clearance on it. I think it has to do with the ball bearing clearance,  something about allowing for heat expansion..... 

But 2 did not..... 

Shouldn't they all be the same as far as the clearance dedication?

I looked up a rebuild kit and the company lists individual bearings too and they seem to use bearings alwith a N on it signifying standard....

So I'm thinking that's what I want to go with for all of them... 

why would you use different ones? Doesn't make sense to me... 

 

And how about brands.... I've found all 4 that I want from nachi( japan), I was gonna get the nsk but made in Poland ..

Any opinion? Trying to put the best quality in and be done with it....

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Sent you a PM.

 

I think it's splitting hairs, and that you'll never find a difference between them.

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17 minutes ago, Stoffregen Motorsports said:

Sent you a PM.

 

I think it's splitting hairs, and that you'll never find a difference between them.

Thanks.... I'm gonna go with the standard N clearance then..... thats what the rebuild company I was looking at was selling.... and I'm going to use nachi. 

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Ahhh, I hate the internet sometimes... I had myself convinced the n clearance is correct. I was trying to get everything in one place but I couldnt get 1... found it on ebay and of course i asked cn or c3, the response was its c3 and it's the one I want for a transmission..... 

Stroffgren I know you said it minimal but there will be a difference... I need to find a chart or something..... 

 

On another note I got the oil pan off today.... I was glad to find no surprises,  i was even able to see the bottom of the cylinder bores, all looks good....

I'll seal that up tomorrow,  also found a small coolant leak, luckily just a slightly loose clamp at the water inlet....

 

 

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So I guess I've convinced myself to use the c3 clearance bearings, I finally figured out the difference between n and c3 and on average it is .0005.... plus the 2 crunchy bearings, both had the tighter tolerance N, the one that had c3 on it felt smooth, 4th was a c3 also but we know what happened to that....

 

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