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Donedreamin

Datsun 521 L20B

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When I'm completely done I will take photos of both sets of rims/tires installed and gather a public consensus. Let me run with this, have faith and enjoy it, even if it's not how you would do it.

everybody is a critic. Don't let them sway you from what you want to do, it's your car, roll with it.
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Lol. Stick with the K5s.

 

He may deny this...But I have a PM from hainz complimenting my truck and its wheels...Which happen to be a set of white PC'd K5s.

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620 front shaft.

 

The early (pre '74) 620 used almost the same transmission as the 521 @26" long. It also used the longer 71B transmissions (same as the 280z) @ 31.5" from '74 on

 

Two if's I can think of.

 

IF the 620 front driveshaft is '74 or newer. It has the longer transmission and shorter driveshaft.

&

IF the 521 and early 620 front driveshafts are the same length.

 

Otherwise shorten the 521 driveshaft by 5.5" and unbolt the spline from the 521 transmission and put a 40mm core or frost plug in the end where the bolt was to keep transmission oil in.

 

Modify the 521 transmission mount like this...

 

F4W63toFS5W71Btransmount.jpg

 

 

wayno is the guy to ask about how much to remove.

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My vote is for k5s but I am biased.  Those or some fresh JDM wheels that nobody has. 

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The early (pre '74) 620 used almost the same transmission as the 521 @26" long. It also used the longer 71B transmissions (same as the 280z) @ 31.5" from '74 on

 

Two if's I can think of.

 

IF the 620 front driveshaft is '74 or newer. It has the longer transmission and shorter driveshaft.

&

IF the 521 and early 620 front driveshafts are the same length.

 

Otherwise shorten the 521 driveshaft by 5.5" and unbolt the spline from the 521 transmission and put a 40mm core or frost plug in the end where the bolt was to keep transmission oil in.

 

Modify the 521 transmission mount like this...

 

F4W63toFS5W71Btransmount.jpg

 

 

wayno is the guy to ask about how much to remove.

I don't know how much needs to be removed, I just make my own mounts from scratch.

I thought there was a photo that had the number that needed to be removed in the photo.

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35868924045_f0c98b43d1_c.jpg

 

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35868918925_9b6dd4b7f6_c.jpg

 

If anyone has any questions about the mods I've done don't hesitate to ask.
The truck isn't running perfect and has a bunch of minor quirks, far from a daily driver but the end is near.

Hope you guys enjoy and thank you for all the wisdom this forum has to offer!

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Agreed, looks great man!  Stereo work?  Like that center console you got going on.  

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I like it..all of that patina.

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Agreed, looks great man!  Stereo work?  Like that center console you got going on.  

The center console was in one of the 620's I used for parts, not sure if it was a factory option or aftermarket to be honest.

The rest is pretty simple, just nice to have music while cruising  B)

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The center console was in one of the 620's I used for parts, not sure if it was a factory option or aftermarket to be honest.

The rest is pretty simple, just nice to have music while cruising  B)

 

I just have a bluetooth speaker and my phone (pandora).  How much is it lowered (3" blocks and re-indexed 1 spline)?  

 

Love what you did with it.  

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It is lowered 4" all the way around, it handles amazing. The best part is it's still a truck and is a great tool. It's always a good conversation piece, it seems a lot of people have owned a datsun at some point in their lives.

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This was the second motorset, the first one had low compression in multiple cylinders

 

36279707941_8974034c44_c.jpg

 

I ordered a factory trans bushing from rockauto but it was no where near the correct one,so I modified the bracket

 

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Front end mocked up

 

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Had some wiring gremlins to sort out

 

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Some more progress

 

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Tidied up some of the hardware

 

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Getting there!

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2ND motor fitted

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Had to slightly modify the exhaust

 

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Night shots

 

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So at this point the truck was running good, as far as the engine goes it felt rather healthy and pulled far better than the 1.6. 
But, unfortunately not everything went as smoothly as planned. My first trip out I drove it to a local car meet and half way there she started bogging and misfiring. 
I managed to get my way home and noticed the number one cylinder spark plug had completely closed it's gap. I readjusted, double checked my compression which wasn't terrible but was the lower of the four, sitting at 140. I wasn't overly concerned at this point. So this is my first run-in with carburetors and i'm not an expert so I popped over to a buddys house for some guidance, he's a mopar guy; not many datsuns guys in my area! 
 

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36371267366_951af82bcc_b.jpgVideo_1 by Done.Dreamin

 

35640895393_35861e9875_b.jpgVideo by Done.Dreamin

 

What happened was where the rocker seats on the valve spring would pop off, I adjusted my that valve to a .05 clearance and it would still pop off. 

So this motor is no good, it's repairable but I am leaning more towards just tossing in a new one but am open to ideas!
Along with that my transmission's bearings are cooked and I have a 5-speed transmission out of a 280z kicking around so that may be the next route.

But one problem I don't have an answer for and perhaps someone can chime in is my clutch disengagement and engagement. I am running a L20B out of a 620, I am using a flywheel out of a 620 and a complete clutch kit out of a 620, including the pressure plate, disc and release bearing and a 4-speed trans out of a 521. I have a brand new slave and master and when I have adjusted at the pedal and at the slave as much as I can and when I press in my clutch I can barely get it into gear, along with that there is alot of mechanical feel in my clutch, it is not a good feeling. I will be pulling it apart but do I have the right combination of parts?

And if I go 5-speed with the 280z transmission what would the correct arrangement of parts be?

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So quick thing... you set the valve lash at .05 ? ... that's really loose...

I think its around .008- .012, ... maybe you ment. 005? Which is a little tight....

Why do you say the motor is no good.... probably just the head that needs some work....

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I had cylinder number 4 intake valve doing that, even the exhaust did it once in that cylinder, for me it was old gas, once I put new fuel in it it quit doing that, sticky valve.

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So is the collar that the release bearing is on also from the 620?

 

The fork is the 521 and the bearing is the 620, thinking this may cause me some issues?

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So quick thing... you set the valve lash at .05 ? ... that's really loose...

I think its around .008- .012, ... maybe you ment. 005? Which is a little tight....

Why do you say the motor is no good.... probably just the head that needs some work....

So initially I reset the valve spring rocker seat and then verified the gap hot between 0.012 and 0.010 can't recall off the top of my head which is intake and exhaust. I started it up and within 20 seconds it popped off again so I made the gap smaller thinking it may rectify it and it popped again. 

 

I do have access to some motors that are in a farmers field still in vehicles, I need to pull the transmission apart anyways. I've never pulled the head on these motors and not sure what the easiest and cheapest route would be, what would you do?

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The fork is the 521 and the bearing is the 620, thinking this may cause me some issues?

The bearing doesn't matter, what matters is what collar the bearing is on, you should be using the 620 collar, if you used the 521 fork and collar, that will be an issue.

You see the collar and the clutch cover/pressure plate are a matched set, the transmission doesn't matter, to be less confusing, you should also have used the 620 fork/collar and put the new release bearing on that collar.

Collars are different heights depending on which flywheel/clutch cover you are using, if you have a 200mm flywheel/clutch cover you use the tallest collar, if you have a 225mm flywheel/clutch cover then it is the medium height collar, and the 240mm flywheel/clutch cover use the short collar.

What happens sometimes is that the wrong collar gets used and either the transmission seems hard to install, or it drops right in and the slave push rod is too short, generally most don't mess up and use the 521 collar, they use the medium collar on their 5 speed swap even though they have a 200mm flywheel, they cannot push the clutch in far enough to totally disengage the clutch.

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I had cylinder number 4 intake valve doing that, even the exhaust did it once in that cylinder, for me it was old gas, once I put new fuel in it it quit doing that, sticky valve.

Maybe one of those fuel treatments to try to clean off the valves ....

You could even try something like seafoam before your next oil change .... cleans out the inside of the motor.... like Wayno said maybe sticky valve...

I'm not a fan of additives like that shit people put in a radiator to "seal it"...

But I know people who use the seafoam and rave about it.....

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Had a coupled days at home, took advantage by pulling an L20 out of a farmers Datsun collection. 

Anyone need 620 wagon parts?

 

 

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Here are some photos I snapped during this years tour, building relationships :D

 

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