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Member Since 10 Oct 2007
Offline Last Active Today, 12:29 PM

#1535142 new here, first 521, first Datsun, finding parts?

Posted by DanielC on Today, 12:16 PM

That air cleaner top is off a later model Datsun.
Take the air cleaner, give us a picture of the carb on the engine.
I noticed the vacuum advance to the distributor is off the manifold. Stock is on ported vacuum off the carb, no vacuum advance at idle.

#1534945 new here, first 521, first Datsun, finding parts?

Posted by DanielC on 15 December 2017 - 10:03 PM

General 521 info.

The bolts on the body are SAE.  Measured in inches, fine thread.  The engine and transmission uses metric fasteners.  The brakes are NOT self adjusting, you have to adjust them, every oil change. 

The running on probably can be fixed by doing a tune up on the engine.  Tune up includes adjusting the valves, .010 intake, .012 exhaust, engine hot, setting the ignition timing, Timing is 10 degrees BTDC, and then setting idle speed and mixture..  I recommend you set the idle mixture with a vacuum gauge, and a tachometer that reads low RPM.  Disconnect the distributor vacuum hose, plug the line.  Tune for best idle at 750 RPM, and then turn in the idle mixture screw to drop the RPM to 700.  This must be done on a hot engine.

If you have not had a 521/L16 on the freeway before the engine is going to sound like it running way too high RPM, 60 MPH is about 4,000 RPM.  that is fine, it will run there all day long, and be happy.


The transmission does not have external linkage.  There is a rod that slides forward and aft, and it rotates slightly.  The rod has a finger on it that goes into a fork in the 1-2, 3-4, and reverse shift rails.  Most of the slop is on the end of the finger, where it goes into the forks on the shift rails.  You can shim the external parts just under the shifter boot, but not a lot.


The seat will be difficult, you need a narrow seat to fit in  a narrow cab.


On a stock 521 the slave cylinder has an adjustment.  It also has a spring to pull the clutch fork and throwout bearing away from the pressure plate.  There needs to be some freeplay, about 1/16 of an inch before the throwout bearing makes contact with the pressure plate.


The heat riser for the exhaust manifold is not likely to be found.   Sheet metal, that gets too hot to keep paint rusts, and after 46 years in the north west, most used one are also not usable.

#1534357 Oil pressure on Z20 engine?

Posted by DanielC on 12 December 2017 - 11:02 AM

On a hot summer day, after being on the freeway for the last hour, at idle, 15 to 20 PSI is OK, as long as it goes up with RPM off idle.


General rule of thumb, 10 PSI per 1K RPM.


If your oil pressure gauge is plumbed correctly, the oil pressure should rise and fall with the tachometer reading,


There is a pressure relief valve in the oil pump, that limits the high oil pressure to 60 to 75? PSI.


See post 139 on this page.  http://community.rat...tsun-521/page-7

#1534060 Cuz Merica

Posted by DanielC on 10 December 2017 - 09:14 AM

It looks to me like the rise in national debt flat lines in July of every odd numbered year.  Will the debt start rising again?

I hope not.


Remember the main purpose of EVERY government agency is to perpetuate and grow itself.   Maybe president Trump being a business man will reverse that.

#1533877 need datsun mechanic !!!

Posted by DanielC on 09 December 2017 - 10:11 AM

To Drexten0,

   What is wrong with your 620?  What do you need to be fixed?


   Back in the day, I used the Volkswagon version of this book.

https://www.amazon.c...ur Datsun alive

#1533823 My Dragon Datsun 521

Posted by DanielC on 08 December 2017 - 10:57 PM

I only have one pair of the chrome door handles, but lots of the plastic ones.
I plumbed the oil pressure gauge today.  When I was using Dragon as a daily driver about 25 years ago,  I used a copper pipe, with compression fittings.  It only leaked a little bit.
I used a 1/4 inch steel line inside the cab, from the gauge to the engine compartment, going through the choke cable hole in the firewall.


This is where the line attaches to the oil pressure gauge.  The line just runs near the bottom of the dashboard, under the combo meter.  I slipped the line in through the glovebox opening, to above the gauge. There, I put two bends in the line, to attach to the gauge.   Before I attached the line to the gauge, I slid the line all the way left, and that gave me enough clearance to poke the engine side of the line out the choke cable hole in the firewall.  I probably need to put in a few small clamps to stop the line from rattling, and hold it below the glove box.
Inside the engine compartment, I put in a coupler, and used -4 Aeroquip SS hose.
I also used this "T" fitting to keep the oil idiot light functioning.  There is an an adapter on the engine oil port to convert 1/8 BSP to the much more common NPT standard.


I made the Aeroquip line this evening. 

#1533692 My Dragon Datsun 521

Posted by DanielC on 08 December 2017 - 11:06 AM

I ordered this carb preheater duct from Amazon
https://www.amazon.c... preheater hose.
I stretched the duct out, cut it in half, and put the two ducts on Dragon.



This is a bent door handle.  The plastic slowly sags when it gets hot.  This is more of a problem in Arizona, than in Oregon, but they sag in Oregon over the years.  One way to fix this is to turn the handle upside down and let it sag back straighter.


Because it is too cold in Oregon, in December for the handle to sag back straight, I used this heat gun to heat the handle up, and gently bend it back straight.


The door handle was also put on the door with the silver sheet metal screws in the picture.  The door is threaded for a #10-32 screw.  I have a bunch of the black #10-32 screws.


The screw holes in the door were slightly damaged by the sheet metal screws.  I chased threads in the holes with a 10-32 tap.


This is the door handle back on the door.

#1533520 My Dragon Datsun 521

Posted by DanielC on 07 December 2017 - 10:18 AM

I did not get a new battery, I got a used one at Pick-n-Pull.   What I look for is a battery that fits into the plastic tray, and is short enough to not be too close to the hood when closed.

#1533335 My Dragon Datsun 521

Posted by DanielC on 06 December 2017 - 01:43 PM

This is a battery I have been using in Dragon for quite a while.  As you can see, the battery has a sticker from April of 2005.  I got this battery used, it spent a few years in a moored boat, and it was discharged fully a few times, and then recharged, but became unreliable in the boat unless the boat was run a few times a week.  But it served several more years in Dragon.  the battery is a group 34 size.


Yesterday, I went to Pick-n-Pull, and got this used battery, also a group 34.  This battery has these  lugs on the side, for a lifting handle, but the lifting lugs get in way of the battery hold down.

The quick and dirty solution is to cut the lugs off, i just used a cross cut saw.


Here I am testing the fit of the battery hold down.  After sawing the lugs off, I had to do a little filing on the remaining part of the lugs. 

The battery hold down now fits, and I clamped the battery in place.

Because the positive battery terminal is so close to the battery hold down, I put a plastic washer over the positive battery terminal, then put the positive battery cable on the battery post.

The battery is now completely installed, and it cranks the truck faster, and more importantly, longer.

#1533129 life

Posted by DanielC on 05 December 2017 - 01:09 PM

Thank you for your service to our country, and on a minor note adding greatly to the Ratsun community.

#1532752 My Dragon Datsun 521

Posted by DanielC on 03 December 2017 - 01:52 PM

I put this blue door on the truck today, just to fill the hole.

My plan is to paint the truck, but I do not have a heater garage.  I can put heat lamps on smaller areas.  I can also put a little heat into the garage, with a small space heater, and if it gets close to warm enough to paint, I can.


i wanted to put a door, any door on the truck, so I can start fitting front fenders.  This truck was involved in a front end collision, and the cowl is pushed back where the top rear part of the fenders pushed on the cowl.

#1532687 My Dragon Datsun 521

Posted by DanielC on 03 December 2017 - 10:41 AM

In the 1970's I put these Stewart Warner gauges in dragon, and this is how they looked before last night.


I used a large file to remove some casting flash on the edges of the aluminium panel, then sanded it with a sanding block, and 400 grit paper, wet.  Then I used the blue one of these brushes in a drill to smooth over the sanding marks.


After that, the gauge mount panel looked like this.
I put the gauge panel back in Dragon.
And then put the cleaned gauges back in the panel.  At one time, I had some fog lights on this truck.  the top hole was for a indicator light, the bottom hole was for the switch.


Wayno got a reply in while I was editing the post.  He likes volt meters.  Volt meters have advantages over a amp meter.


In the 1970's we used amp meters and we liked it.  Most cars that had a gauge to monitor what is going on with the charging system used amp meters. 


It is much easier to wire a voltmeter, especially on a 521, because a 521 used the positive battery cable to the starter to carry charging current from the alternator to the battery.   Charging current goes on one cable to the battery, discharging current goes on another thick wire, to the fuse box.


Since the amp meter reads both a charge from the alternator, and a discharge from the battery, you need to do some rewiring to make an amp meter read correctly.


First, you need to run a wire from the positive out of the alternator to the fusebox.  This wire needs to be big enough to handle the full output of the alternator.  For a 50 amp alternator, you need a bare minimum of a 10 gauge wire, and probably should use a 8 gauge wire.  Higher output alternators, even bigger wire. 


Then you need two more wires from the fusebox to the gauge.  One wire goes from the fusebox to the gauge.  The original wire from the battery to the fuse box is disconnected from the fuse box, and reconnected to the second wire going to the amp gauge.


Both of these wires need to be able to carry the full alternator output.  These wires are going into the cab.  You need to make sure these wires are very well insulated, and protected from any sheet metal edges.  Since these wires are directly connected to both the alternator and the battery, if they short to the cab, it is possible to have a few hundred amps of current in a short circuit situation on these wires.   These wires are always hot.  Another problem is the addition of the resistance of several feet of even a heavy gauge wire causes a voltage drop in the alternator output, so the alternator has to work harder to make up the difference.


A voltmeter only needs a single pretty thin (16 gauge) wire to connect. 


I have the amp meter.  A volt meter to match the oil gauge is about $45.00 to purchase.

#1532638 Cuz Merica

Posted by DanielC on 03 December 2017 - 06:22 AM

The tax bill is in reconciliation between the house of representatives, and the senate.  What will matter to us is the bill that gets signed by the president, later.


Tax revenue into the government is dynamic.  The numbers we are being told are based based on a static estimate, by the congressional budget office.  If taxes are lowered, the revenue in many cases actually goes up, because more total income is made, and a lower percentage rate of a greatly higher total income means more total revenue.


Put another way, lets say only 1% of the unemployed people get a job.  They start paying taxes, and also no longer need welfare from the government, and therefore the revenue goes up, and the amount the government has to pay out drops.  That change to the government revenue will be higher than 1%.

#1532637 Is this alternator behaviour weird?

Posted by DanielC on 03 December 2017 - 06:06 AM

Sometimes the voltage regulator is temperature compensated.   "Normal" range is 13.5 to 14.5 volts. 

It would be OK to have slightly higher voltages in your truck, but if you are not having any problems, you could just live with it.  If you can come up with a spare alternator, I would keep one around.

#1532551 Cuz Merica

Posted by DanielC on 02 December 2017 - 02:16 PM

You are not subsidising my heath care.  Last time I needed health care, I paid the hospital myself.  If you subsidising anyone, it is insurance corporations.