My 1971 521

[d.p]

19 minutes ago, Crashtd420 said:

It will work you'll just have to shorten the drive shaft, modify the rear mount and the shifter will move back a few inches.   

Any idea if it will allow me retain my bench? 

[datzenmike]

31.5" long. so your driveshaft would need trimming about 5.5" to fit and the rear transmission mount modified. The 521 driveshaft spline can be used but the end needs a 40mm core plug and some sealer to keep the transmission juice inside.

 

 

Or make one...

 

 

 

 

 

 

 

 

 

This one is a pre '80s 71B. I don't know what they were used in overseas but If you put in first gear and mark the input and the tail splines and turn 20 times, the tail spline will make 5.5 turns IF it's a wide ratio. The wide ratio HERE, was only used on the '79 620 paired with a 4.11 differential. 

 

The '80 2wd 720 also used this combination but this isn't an '80 transmission.

 

 

My 710 had the same style 4 speed as the 521 with the bottom bolt on cover plate. I put a long 71B 5 speed in and didn't have to modify the hole. The shifter on the 4 speed is mounted right over the end of the transmission. The 71B shifter is slightly forward which helps cancel out any difference.

 

[d.p]

Supposedly rebuilt NOS from Japan but other than those pics and the length not much else is known about it.  But by the looks it will work? 

[datzenmike]

I added something about the shifter location. Add to that that you can always bend the shifter to clear the seat.

 

Yes, it can be made to fit.

 

EVERYTHING from Japan is NOS. DON'T believe it. NOS means never sold or installed and pulled directly from a a warehouse inventory. Can also stand for New Obsolete Stock, again never sold but superseded by a new part. Stretching the definition, a part, bought, but never installed and still in an unopened package is close to NOS. So you can see that real NOS parts are exceedingly rare. Most are re-pops from SE Asia. Hey you might have lucked out but don't buy it because it's 'NOS from Japan'. All 71Bs are from Japan.

 

 Someone welded a bolt on the fill bung. So take the NOS with a grain of salt.

[d.p]

More pics. 

 

 

 

[datzenmike]

 Nice. We didn't get that sticker, what does it say?

[d.p]

1 hour ago, datzenmike said:

 Nice. We didn't get that sticker, what does it say?

no idea but the fill hole is on the left, is that weird?  I thought my full hole on my 4 speed is on the right (pass) side.  

[datzenmike]

I'm sure I've seen the fill hole on the right side in some Z cars and if you look there's a casting boss on the oposite side. Z cars tend to be on the right, trucks on the left but??? this is not way to ID them.

[Stoffregen Motorsports]

I used to drill and tap that other hole to make it easier to fill the trans without the exhaust in the way. So fill hole on right side is a bonus.

[d.p]

No idea what the sticker says.  Is the bung a bad thing? If I can get for a good price I might as well. Don’t see many of these this side of the country.  

[datzenmike]

Sure. give it a shot.

[d.p]

26 minutes ago, datzenmike said:

Sure. give it a shot.

from what you can tell from the PICS it’s a without a doubt a FS5W71B?

[d.p]

Does the serial on the trans denote the year? 7931350

 

 

[datzenmike]

The serial # is on top of the bell behind where the head would be.

 

On the automatics it does but I've never got the 71B manuals to agree. Probably because by now a survivor of 40+ years may have been swapped. If I said it was made in September of 77 would that agree with what you know about what it came out of???

 

All I can say with certainty is what it ISN'T.

Made  before '80 model years.

L series 5 speed

IF it's a wide ratio (see above post for determining) then here it would have been in the '79 620. Over there maybe a Cedric or GTR or Fairlady, I don't know what they had back then and in Japan.

IF a mid ratio with 6 turns then '77-'78 280z or first year '79 zx, 810, '77 through '78 620.

[d.p]

On 3/3/2020 at 10:31 PM, datzenmike said:

 

YES.... if no one had replaced it.

 

I had a 521 years ago and put an L20B in and it worked just fine. I knew nothing about the different clutches and matched release bearings. So I hear that the L20Bs had 225mm clutches and the L16 bearing won't work. WTF? Well turns out the L20B was from a car so it all went together smoothly but I didn't know this at the time. It could have been a shit show.

 

200mm 5 bolt. The L20B looks the same but 6 bolt.

revisiting this while I wait for primer to dry.  This is my flywheel: 

 

 

Good to order that heavy duty one you talked about before hainz??

[datzenmike]

This is a car L20B flywheel. If you can't find the Roadster PP there are 225 and 240 6 bolt ones. The 240 will take a 280zx or 300zx turbo pressure plate and disc r even the D21 Hardbody PP known as the White Bunny swap..

[d.p]

7 minutes ago, datzenmike said:

This is a car L20B flywheel. If you can't find the Roadster PP there are 225 and 240 6 bolt ones. The 240 will take a 280zx or 300zx turbo pressure plate and disc r even the D21 Hardbody PP known as the White Bunny swap..

I didn’t understand a word you said Mike. I was asking if I could get the clutch Hainz was walking about before.   They heavy duty one from Datsun parts IIRC.  That would work with my current 4 speed?

 

IF I were to get that 5 speed then I would need a new pressure plate and different clutch?  IE use one of the ones you are taking about?  

[datzenmike]

All Hainz ever mentions is the Roadster pressure plate option. Super HD 200mm. I don't think Nissan has any left any more. So that leaves another supplier and it's probably a generic (fits Ford 6 cylinder or something) unit. May be equivalent to a Stage 2 or 3 Exedy....  or something else. The Roadster PP is 30210-20111 and has a clamping force of 650 KG. That's 1,425 pounds in American. It ain't going to slip. What ever you get, compare it to that.

 

The 240mm 300zx is 30210-P9600 and 600Kg. Nissan might have them still as they are 12 years newer.

 

 

Your clutch and pp have nothing to do with the transmission choice. You can run what ever combo clutch you like.

[d.p]

Ok we are talking about the same thing then. 
 

this one: https://www.datsunparts.com/1483

[datzenmike]

The one and only.

[DanielC]

"Any idea if it will allow me retain my bench?  "

Both Dragon and Ratsun, two of my 521 trucks have the long five speed transmission in them.  I have the stock bench seat all the way back, in both trucks.

Ratsun has about 2 1/2 or 3 finger widths between the seat and shift lever in 2nd/4th/REV.

Dragon has about 4 finger widths between the seat and shift lever in 2nd/4th/REV.

 

This picture is two heater cover plates, and the plate that covers the hole in the center of the cab, over the transmission.  this should give you a good idea of where the shifter hole needs to be.

 

Transmission in 2nd gear, in Dragon.

[d.p]

Thanks Dan that helps ALOT. 

[wayno]

Personally if you can find one on the east coast I would go with a 240mm Nissan 720 Z24 flywheel/disc/clutch cover/collar, they last a long time on my work truck, they will last forever on your Datsun 521 fun driver unless you don't know how to use a clutch.

[banzai510(hainz)]

NSC 581 Exedy. 600 pound pres plate .Shit buy 2 at that price
yes it’s a cheaper Roadster clutch set up 

use your 521 T/O collar and bearing 

 

you should be writing these numbers down when I give them out and create a part note book with size type ect lace to purchase ect....

Edited April 12, 2020 by banzai510(hainz)

[d.p]

A notebook?  Lol who uses them anymore? Kidding. 
 

not sure anyone remembers or cares but the crank pulley on this engine had a ton of nicks/marks so I really had no idea what was what but am able to find TDC now.   
 

 

Need to get some black spray paint to finish painting the pan, pulley and vent pipe then I should be good.  The vent pipe had what looked part of a rubber hose inside one end and not sure why? 
 

Another question I do have is should I replace the chain and or guides?  Guides have slight grooves in them but nothing major.