1979 Datsun 620 Gas tank

[stingraylx1]

20 plus years sitting, need advice.

 

Truck started, I bypassed the fuel system feeding a outboard gas tank directly into mechanical fuel pump, replaced all rubber gas lines within engine bay but did not mess with the OE pump other than running 6 gallons of treated gas heavy on sea foam and marvels mystery oil. Pump seems to be be rock solid and functional compared to a new China POS pump. Should I disassemble the OE pump, clean, inspect only and test fuel pressure or leave it alone.

The fuel tank is rusted and has some big dents from rolling over stuff. I plan on pulling it, back flushing the metal fuel lines and using a copper electrical wire to rod them out and replacing all rubber fuel hoses for inlet and return lines.

 

Should I try to clean with solvent, metal BB shot or gravel and shake it or should I have it dippped at a radiator repair shop?

 

Or  a dorman replacement 720 tank?  Any input on exact Dorman PN for the 79 King cab. Do I need to modify hose connections, fuel sending unit, fuel pickup or it it plug and play.

 

Will it bolt to frame without modifications.

 

1979 620 KIng cab.

 

Thanks

 

[Goemon]

720 tank will fit 78-79 620.
I am converting a 79 longbed frame to a KC frame for my 79 KC

Front & rear bolt holes are spot on. I got a Spectra delivered to Auto Zone

Now you have to find a 555 left side rod assembly for me...the last 555 steering part I need ... :-)
I have newer Nissan Cab lights for the KC

[Goemon]

The check valve on the tank is still available through Nissan.

[stingraylx1]

Nice work and the frame is clean, do you have the PN,s for the spectra gas tank and Nissan oe check valve.

What about the fuel sending unit, did you replace?

 

The 555 left side is tough, I bought one nos on eBay from Cyprus for 39.00 plus 20.00 shipping, waiting on package.

 

I have all 555 parts for front except the center link assembly, I bought a alternative but still seeking a 555 center link assembly. 

[Goemon]

MOOG, TRW, VERA, all sell 555 in some boxes. I REALLY need the TRW or MOOG number .
The right side is ES2339A. 555 number is  SS 4110L. I can't find the left  number for the other two parts distributors.
Is yours coming in a 555 box or another box? If so, I need that " ES "  Left side number, thanks

 Check Valve is 17330-P7900, I got mine at the dealer. Clip came from  a 720

This is the cheapest tank I found online but I didn't look far.  Didn't read about shipping
https://www.walmart.com/ip/spectra-premium-ns6-fuel-tank/180118469

I rebuilt my sending unit, I zinc plated the big part & nickle plated the float rod & did an Ohm test
after repairs and then before it all went back together.
A 720 sender will work, same Ohms.

[Goemon]

The frame is slowing coming along.
I will be needing that part around springtime

[Goemon]

I am working on getting torsion bar boots made
I have the test ones here now.
 

[Goemon]

There is a 720 sender for sale on the 720 page 40 USD + shipping.
For a KC so some tweeking on the longer rod may be in order but they use the same Ohm measurements.

https://www.facebook.com/groups/401090363680935?hoisted_section_header_type=recently_seen&multi_permalinks=1368647156925246

[Goemon]

Don't mess with the fuel pump, I have an Atsugi that is original and still working since 1979,
opening the unit  might damage it.
You can find some NOS pumps, NIKKI mostly, on Fee Bay.
I was lucky enough to find a NOS Atsugi 6 hole unit

[stingraylx1]

I will send you the detail of the 555 when it arrives, I hope it’s the real deal.

 

Torsion bar boots, let me know how they turn out, I would be interested if possible.

 

Fuel pump is working, OE it is… 

 

Good info for the tank, I plan on replacing 

 

looking for a windshield seal with trim option, I ordered a precision wbl271 for 34 bucks but would like to keep the trim if possible.

 

How many hours will you have in the frame and did you blast it?

 

 

 

 

 

 

 

[Goemon]

There was hardly any rust on the frame. A lot of it still has paint. What rust is there is extremely light.
I only sandblasted the parts the wire brush on a die grinder can't get to. The frame lived most it's life in Cali.

The frame is taking a long time since I rarely have any help and I am 60.
It took over 6 months to get it to GA from NC. for a reasonable delivery price.

I noticed a difference in the 3rd member casting. This replacement frame was for longbed . I am converting to KC.
The frame must have had a 5 speed. It has a   4.37 ratio  chunk and the 79 4 speed has a 4.11
The 4.37 in the pic with no line in the cast & the 4.11 that has the line in the cast.

I am interested if your 79 has the same line on the 3rd member, AKA chunk.....??????

That is my sandblaster in the bucket that I use when parts are to big to put in the cabinet
I sandblasted the 4.37 chunk before I  removed it, I used on my driveshaft also

As far as the front windscreen seal, I am pretty sure these people can make them if you have a pattern.
If you had some made they would sell fast
https://www.gggcorp.com/Universal_Mouldings.html

[stingraylx1]

Nice work, I will verify the rear diff this weekend, truck is up north and plan on going up this weekend.

[EDM620]

On 11/17/2021 at 2:38 AM, Goemon said:

720 tank will fit 78-79 620.

On the plus side, the 720 tank for a 4WD is a bit deeper thus giving you some added fuel capacity, there are 4 variations in the tanks as a result (reg/KC, 2/4wd). Earlier 620 tanks were actually mounted to the underside of the box.

 

On 11/23/2021 at 8:36 AM, Goemon said:

The frame is taking a long time since I rarely have any help and I am 60.

I fully understand your situation, I'm 59 with a F'd L hip so many tasks are quite a pain literally for me to do. I built myself a rotisserie and wish I'd done that much earlier in my build as it makes it way easier to work on the project.

[Goemon]

I have a bad hip & lower back, no fun.

[Goemon]

Made some progress. The rear is back on the ground now & the front tires are up.
Ready to start attacking the steering & front suspension.

I found that some 720's had the inspection light.
I got this one for 45 bucks shipped and used a bit of Neverdull on it

[datzenmike]

With several slight variations, optional on several Datsuns including the Roadster, S30, 610, S10.... That one is in excellent shape.

[Goemon]

Looking for someone reproducing the dome gasket.
Datsun Makers' site is not helpful so far..
I am working on the heater valve stop washer.
They should fit lots of Datsuns. I hope to have them produced at a dozen at a time.