Just purchased a 1966 Datsun 520

[difrangia]

I went through three cork gaskets on our E1 engine in the 320 (it has the early head with two rocker studs securing the  rocker cover instead of six screws or so) and finally sprung for a silicone gasket for a British Austin/Morris engine, as they are are first cousins, and no more leaks !! The silicon gasket was about 24 USD and well worth it !! Don't know if the Brits make a silicone gasket for the multi-screw cover but that's what I'd look for  if that's what you've got. Put the silicon gasket on three years ago and not a problem since.

 

On the tank sender, I'm not familiar with the 520 tank, but does the sender mount in the horizontal top surface of the tank or into the side or at an angle ? If it mounts straight down into the top of the tank, I might have some suggestions. 

 

You have a beautiful old uncommon survivor there. Rarer than hen's teeth, especially on east coast. I'd not change anything that couldn't be easily put back original on it.

 

Keep on Truckin' !!

 

[iota]

Thanks for all the help & advice guys! This past weekend we worked on the truck more an were able to install the disc brake conversion kit which went smoothly. I have a Wilwood adjustable brake proportioning valve and a dual-reservoir master cylinder that will hopefully go in this weekend, but just from test driving up and down the street the truck is stopping great. Previously, stopping power could be best described as mediocre at best, so I am glad to have some serious brakes on there now.

 

I also replaced the distributor (and cap/rotor) with the one I got from RockAuto. The one in the vehicle had a crack in the housing where the distributor cap snapped on, and had a lot of play in the shaft. After replacing the distributor stuff, I was able to set the timing without issue.

 

I also removed the rocker cover and adjusted the valve lash. It looks like there is a little bit of coolant milkshake in the oil around the #1 valves, so at some point if I can find a head gasket I'll remove the head and check everything. The top end of the motor is very noisy, even after adjusting the valves and setting the timing - it doesn't run nearly as smooth as I would hope. I suspect I probably need tappets or something else cam/valve/head related to be replaced/resurfaced but I'm not an expert.

 

Any suggestions on where to get top end rebuild parts like tappets, head gasket, etc would be much appreciated. I've been Googling around without much luck so far.

 

Also picked up some original hubcaps on eBay, beat the dents out of the hood a little bit and just doing some wiring cleanup (the horn button doesn't work, and the left turn signal doesn't work reliably, so I've got to figure out how to get those apart and checked out at some point)

 

[Charlie69]

Brakes look good!

 

Do not run the engine much with the water/antifreeze in the oil, it will take out the bearings quick.

[Charlie69]

Posted this accidentally in Crastd420's trhead.

 

I see the best tech there is on the timing.

 

[Crashtd420]

Your killing me...  that was greaser2s thread.  .

[iota]

Work continues on the truck:

 

We've got the aftermarket electric fuel pump out and the original fuel pump repaired. I ordered a J15 mechanical fuel pump from Thailand on eBay and ended up swapping the diaphragm and the "top" of the new pump onto the original one. The J15 pump from eBay wouldn't fit as is - the arm was wrong shape/too short obviously, and swapping the arm from the old pump wouldn't work as the mounting flange was too thick so you couldn't bolt it back down. The old fuel pump was caked with gasoline varnish and inoperable so swapping the internals and top half of the pump worked. Now the engine compartment looks closer to stock and no more nosy aftermarket 12v pump (which I had added temporarily to get it running). 
 

I also added a Wilwood brake proportioning valve on the rear line but still need to get it dialed in now that we have front discs. 
 

Was also able to replace the broken fuel level sender - the original one was totally rotted away from rust. A cheap one from Thailand via eBay worked, but I had to use the bench grinder to remove a "lip" on the round part that goes under the lock ring on the tank - it was too thick to fit. The stock fuel pump had the ~15mm elbow for tank vent and the new one doesn't have that, but for now I'll just run it without filling the tank all the way up and it should be fine. Will probably just put a hose barb and elbow in the tank or the sender if I can fit. Can't complain for how cheap it was. 
 

Has anyone had any luck finding a head gasket for the J13? I've seen a few part numbers on some auto part sites but nobody seems to have them in stock and I'm stuck. I'd like to change the head gasket and resurface the head to keep coolant out of the engine

[dat521gatherer]

Very nice truck. I notice you have the super rare one year only glovebox knob. It might have been available for less than a year. Hard to tell but it looks like original tailgate chains.

[iota]

Thank you! Yes it has the original glove box knob, which developed a crack through the middle the first time I grabbed it and pulled on it. Now we don't touch it 😁

I believe the chains are original as well, they are the exact same color as the body, best I can tell. Noisy as hell when driving but they do work to hold the tailgate flat. Cool little grab hooks on them too. 
 

 

For everyone following along with this project we have been driving the truck around our little town whenever we get the chance, and it runs great and stops great. Feels 100% reliable (knock on wood), and after sea foam the crank case and gas and doing another oil change, I haven't seen any more discolored oil under the rocker cover.  Have been working on just fixing little bugs (like the original ignition relay wire to the key didn't work - traced the issue to the plug behind the glove box which needed to be cleaned with contact cleaner). 
 

The wife is planning to rehab the steering wheel to fill in the cracks with one of those repair kits from Eastwood or similar (I need to find a super cheap wheel we can use temporarily while she works on it first). She's also got plans to redo the missing headliner and seat and doors with something closer to the original, as well as repainting the metal dash cal black. 
 

I'll keep tinkering with it, we are having fun. Thanks to everyone for all the tips and advice!

[iota]

Oh, we want to get it ready for cruise-ins next month. The original paint has plenty of minor blemishes that could easily be polished out. I would love to buff the vehicle back to a real shine, but I've never messed with paint this old and don't want to either screw it up, or ruin the look. Also concerned about the tailgate which has big rust spot and spray can paint marks from a previous owner - might look weird to have the paint shining & waxed and a big rusty spot there. Open to ideas on what to do and not to do with the finish. 

[Charlie69]

Have a good body shop fix the hood and the tail gate touch up paint as needed.  The color matching done by computer can result in amazing matches.

[iota]

A little bad news. A while back I got the J15 mechanical fuel pump off eBay and swapped the "top" of the pump onto the "bottom" of our original pump, which worked great. However, it was leaking a little oil and when I really got in there with a flashlight I realized there was a black plastic spacer that was basically melted to the block and covered with oil that I hadn't seen before. After removing this spacer and cleaning up the block, I realized that I could just use the entire "new" pump with the old arm and it would fit! So I swapped everything back to the new pump and transferred the original arm from my old pump to the new, and it bolted up and worked perfectly - no leaks at all.

Drove it about 10 miles and then heard a "pop" and within a minute was on the side of the road with no fuel pressure 🤦🏻‍♂️ Swapped back to the electrical fuel pump to get home and it ran fine, but now when I took out the mechanical fuel pump my worst fear was confirmed: the arm (my original Datsun one) had snapped off! I'm guessing that there must have been some very minor variation in the angle or "depth" that the new fuel pump worked the arm, and it just got bound up somehow - not really sure what happened, since the old pump with the spacer was identical to the new pump without the spacer, but what can you do. 

 

I guess I am going to have to drop the oil pan to retrieve the broken arm, and then for now I'll just drill a couple holes in a pieces of steel plate and bolt them to the side as a plug over the fuel pump port and just use the electric pump. If anyone knows where to find the proper arm so I can go back to my "frankenstein" half original/half new pump, let me know!

 

[wayno]

All Datsun/Nissan fuel pumps use that spacer, when removed that arm was likely being torqued/flexed/tested to the limit and it finally broke.

What made you think it would not work the way it was before with the plastic spacer in place?

[iota]

9 minutes ago, wayno said:

What made you think it would not work the way it was before with the plastic spacer in place?

 

I didn't even notice the spacer there when working on the vehicle previously, it was so caked with oil and kinda melted on to the block. However, my new pump that I got from eBay had a thicker mounting flange than the stock pump. At first, before I realized there was a spacer, I assumed just meant it wouldn't fit - so I swapped the "bottom" of the original pump with the internals and "top" of the new pump and put it back on the now-leaking spacer. Once I realized the spacer was the issue, a lightbulb went off: the reason the new pump had a thicker mounting flange is because it was made to be used without the spacer (or so I thought). Guess that didn't work out exactly as I planned, but it did work fine up until the moment that it didn't work 🙂

 

In this picture (from when I had combined the old pump and the new pump), you can see the old pump has a ~1/4" thick mounting flange, and the new pump has a ~1/2" mounting flange. When I removed the spacer and held the old pump+spacer side by side with the new pump(no spacer), everything lined up perfectly so I figured it was just a simplified design that didn't need the spacer. Guessing that there must have been a slight geometry change that I didn't notice

 

[wayno]

Your kinda in an area that not many people on Ratsun are in, the J block is not popular engine, not many even bother getting them started when they get/buy a truck with one, they just remove them and install an L block or some other more modern engine, for this reason not many know a lot about the engine.

It likely needed the thick base(mount flange) for that arm, if it was cheap enough buy another one and save the broken one for rebuild parts for the future as it is new.

 

[iota]

Yeah, thats my problem - the arm that broke is the original one for the truck; the arm that came with the pump (which was intended for a J15) is much shorter and straight. I'm not sure how to find one of the "proper" arms, short of just picking up different ones on ebay and trying to find a match (and that's what I think I'm going to do, while using the electric fuel pump in the interim)

[R4wb33]

Would it be possible to weld the broken arm back together?

[iota]

2 minutes ago, R4wb33 said:

Would it be possible to weld the broken arm back together?

I may try that if all else fails (or I may just say screw it and stick with the electric fuel pump forever and just be done with it); it's going to be super tiny surgery to do so, though, because its a really pretty small piece. Hopefully doesn't come to that 😉 

[Charlie69]

Stay with the electric pump.  3 to 4 lbs. pressure is all to want for the carb.

[cnpbaker]

That's a sweet 520 and  I love the color. I bought a 68 520 but prefer the single headlamp. I just love the style of these classic trucks, head turners for sure.

[iota]

The truck has been parked for the last 2 weeks since the fuel pump actuator arm broke off, just as a precaution. Today I pulled the oil pan bolts so I can get the arm back and figured I'd clean and inspect what I can while the pan is off. 
 

Obviously the pan won't come out due to the tie rod and/or the crossmember under the engine. What's the preferred method for getting the pan off with the least drama - pull the engine mount nuts, or remove the crossmember, or remove the tie rod, or is there a trick? I haven't attempted anything yet (was hoping it would squeeze out but there's no way), figured I'd check with the experts here before starting on the job tomorrow 

Edited March 2, 2020 by iota

[wayno]

I would remove the cross bar with 4 bolts, but if that frame has ever been tweaked it may be nearly impossible to get it back on and you need it there.

 

[Charlie69]

Do as Wayno suggested just have the frof the truck up on secure jacks stands.  Years ago I had the problem Wayno metioned a since I had th weigh of the truck on the 2 jack stands I was able to gaet 2" ratchet strap around the front frame rails and I lifted the truck up off the jack stands with my floor jack on the front frame rail (this is very dangerous)  but I was abl to tighen th ratchet stap eough to get the bolt holes lined up.  Be sure if you have to do this you have to bolts in the cros member so you only have to ge 2 bolts in while you are under it.  This a situation where I would like to have a 2 position jack like Wayno has 2 of.

 

 

 

[iota]

Just an update on this, the oil pan project went off without too much drama. I got a replacement oil pan gasket from New Datsun Parts and my wife pulled the crossmember and the pan without issue. We pressure washed and used a wire wheel to get the crud off the outside of both, and then used self-etching primer and engine enamel paint on the outside of both. Cleaned up the inside of the oil pan (which was actually in great shape), retrieved the missing pump arm & spring, and were able to reinstall everything without too much trouble - I got new grade 8 bolts to replace the old crossmember bolts and so we could just hit the last one with a hammer to get it into place and it worked out fine. Oil change and a test drive later and everything is working great. The small block Chevy block-off plate from Amazon worked fine with the addition of a couple washers so it would fit tightly on the engine's studs. We are sticking with the electric pump for now (noisy but reliable)

 

After a ~5 mile test drive, I noticed the hood was warm and there was a lot of coolant spray on the steering box and driver's fender well from the radiator overflow tube, so now I need to figure out why it's getting hot... It's a never ending project!

Edited March 19, 2020 by iota

[datzenmike]

Well make sure the rad cap rubber seal is ok and the pressure relief (about 13 PSI) is working.

 

 

 

Two major things causing overheating.... lack of air flow and lack of water flow

 

AIR

1/ Check the fan for damage and the belt is adjusted tight.

2/ May or may not have come with a shroud around the fan, but a shroud increases cooling efficiency.

3/ Bugs or dirt blocking air flow through the cooling fins.

4/ May or may not have a rubber skirt across the front of the hood that when closed seals between it and the rad support so air cannot get past and has to go through the rad.

 

 

WATER

1/ Bad rad cap

2/ Soft lower rad hose combined with a rad full of scale. The increased effort to push water through causes a suction that collapses the bottom hose. 

3/ Scaly rad from years of topping up with water containing dissolved minerals in it. Seen through the rad cap opening. Always use distilled water.

4/ Failed thermostat, stuck and can't fully open or wrong heat range.

5/ Non operating or leaking heater with the two hoses connected to by pass it. This water also by passes the rad and comes out hot from the engine and goes right back in uncooled adding to the burden on the rad. If joining the hoses together be sure that there is a plug and no flow through them. 

 

 

Another cause worth mentioning is a head gasket that is blowing. Under load the compression is blowing out into the cooling system. This will over pressurize it and spit coolant out the over flow tube. Warm up and idle with the rad cap off. You may notice the occasional bubble float up. Rev it a few times, see if this increases.

 

SCALE

I have removed a rad and faced it down with the capon and the hose ends up. Fill with CLR and let sit over night. Won't hurt to shake the mixture around. The CLR will dissolve the hard water scale from the inside.

 

Always use a 50/50 mix of distilled water and a premium brand of antifreeze coolant.

[iota]

Great info, thank you. The radiator cap is probably the issue. The "filler neck" where the cap goes has a notch cut out of it, about ~1" long and maybe 3/4" down. This keeps the cap from sealing tightly. Someone mentioned it was an old mechanics trick to prevent overheating but now I think that the radiator cap (which looks new in the last 20 years) just doesn't seal well, and is probably letting air in or otherwise not doing it's job right.

 

I'll get a picture, not sure of exactly how to fix it. I had knocked the radiator cap off while working under the hood recently (since it doesn't "lock" very well with 1/3rd of the ring it snaps to missing, of course) so maybe when I put it back, it just didn't get tight enough. Hopefully it's nothing more than that but I'll investigate the other items you listed just in case