That's pretty much what I understand of the hydrogen prob, but the blip I saw on it made it sound like the item could be cooked at 400deg for X amount of time and release the hydrogen. Maybe I'll have time in the next week or so to research it.
My 521 "get it running again"
Over the last few days, I have been working on tail light assemblies, and licence plate light. I removed the tail light assemblies from the truck I want to get running, and the tail light assemblies, and licence plate from a second truck truck I have. It is so nice having my own parts truck. I also have tail light assemblies from a third truck.
Using parts from the six light assemblies I have, I now have four tail light assemblies that are working, in good shape, clean, and almost ready to use. It would be nice to paint the metal light frame, maybe I will get to it, soon.
I took apart the light assemblies, cleaned them, polished the lenses a little, did some minor straightening on the frames of them, cleaned out the not to badly rusted sockets, and tested the wiring harness, and reassembled them.
As near as I can tell, the only part that is right or left on the tail light assembly is the frame. The rounded corner of the frame goes down, and there is a small tab that indexes on the clear reverse light lense. If you have a right side metal frame, and a left hand assembly, you can turn the white plastic reflector and it goes on the other side, you can turn the red and clear lenses upside down, and it goes on the other side, and you can put the left side wiring harness on the right side. The gasket has some drain holes on the bottom, if you use a right side gasket on the left side, turn it upside down, after flipping it end for end.
The screws that hold the tail light frame to the brackets on the bed of the truck are an American 10-32 thread. I do not yet know what the thread is on the tail light frame, yet.
I need to do some repair on some broken studs on the two frames I have left. The last two harnesses I have, have got some very badly rusted sockets, and also have been butchered by some one (maybe me) trying to hook up trailer lights. The reflectors have got some funny decaying by the reverse lights (heat damage?) and the gasket for one is torn. The red and clear lenses are in ok shape, two minor cracks that I think will be hidden when the assembly is back together.
The licence plate light just needs cleaning, rust removed, and painted.
Using parts from the six light assemblies I have, I now have four tail light assemblies that are working, in good shape, clean, and almost ready to use. It would be nice to paint the metal light frame, maybe I will get to it, soon.
I took apart the light assemblies, cleaned them, polished the lenses a little, did some minor straightening on the frames of them, cleaned out the not to badly rusted sockets, and tested the wiring harness, and reassembled them.
As near as I can tell, the only part that is right or left on the tail light assembly is the frame. The rounded corner of the frame goes down, and there is a small tab that indexes on the clear reverse light lense. If you have a right side metal frame, and a left hand assembly, you can turn the white plastic reflector and it goes on the other side, you can turn the red and clear lenses upside down, and it goes on the other side, and you can put the left side wiring harness on the right side. The gasket has some drain holes on the bottom, if you use a right side gasket on the left side, turn it upside down, after flipping it end for end.
The screws that hold the tail light frame to the brackets on the bed of the truck are an American 10-32 thread. I do not yet know what the thread is on the tail light frame, yet.
I need to do some repair on some broken studs on the two frames I have left. The last two harnesses I have, have got some very badly rusted sockets, and also have been butchered by some one (maybe me) trying to hook up trailer lights. The reflectors have got some funny decaying by the reverse lights (heat damage?) and the gasket for one is torn. The red and clear lenses are in ok shape, two minor cracks that I think will be hidden when the assembly is back together.
The licence plate light just needs cleaning, rust removed, and painted.
It has been a long time, but here is another update. I have been doing some sheet metal work on my Datsun 521 pickups, and I also put new kingpins in the one I want to get running first. I could not get the most promising L-16 to run, have not investigated why. I ended up getting another L-16 cylinder head valve job done, and put that head on the L-18 engine I have.
The L-18 cylinder head has a crack in the water jacket, under the valve springs, and I keep getting advise to scrap the head. I do not want to, the is a high compression "peanut" head.
I pulled the L-16 engine I hoped would run out of the truck I was working on, and put the L-18, with the L-16 cylinder head back in the truck. Long story short, I got the L-18 running tonight. Good oil pressure, good vacuum at idle, and starts almost instantly when warm. This is with the old carburetor, that has not been run for a few, or several years. Used plugs, old spark plug wires, old distributer cap, and rotor. Now, I need to work on hydraulics. The clutch does not work. The front brakes were not put in after the kingpin job, they were bad. The drums are badly worn, rusted, and probably oversized. The shoes had metal contact with the drums. The wheel cylinder is probably bad. The brake master cylinder is probably bad, I will not know until I get the wheel cylinders in good shape.
The L-18 cylinder head has a crack in the water jacket, under the valve springs, and I keep getting advise to scrap the head. I do not want to, the is a high compression "peanut" head.
I pulled the L-16 engine I hoped would run out of the truck I was working on, and put the L-18, with the L-16 cylinder head back in the truck. Long story short, I got the L-18 running tonight. Good oil pressure, good vacuum at idle, and starts almost instantly when warm. This is with the old carburetor, that has not been run for a few, or several years. Used plugs, old spark plug wires, old distributer cap, and rotor. Now, I need to work on hydraulics. The clutch does not work. The front brakes were not put in after the kingpin job, they were bad. The drums are badly worn, rusted, and probably oversized. The shoes had metal contact with the drums. The wheel cylinder is probably bad. The brake master cylinder is probably bad, I will not know until I get the wheel cylinders in good shape.
My Datsun finally moved itself today. Clutch not disengageing, no hydraulic brakes, but the emergency brake works. Not registered yet.
It starts very easy. It is just above freezing outside, but the engine fired right up. I warmed the engine up, and then backed it out of the garage by starting it in reverse. Took some pictures of it, and then started it up, and drove it around in a circle in the yard, and back into the garage. Got it close in the garage where I wanted it, and then pulled the coil wire, and just used the starter to move it.
It starts very easy. It is just above freezing outside, but the engine fired right up. I warmed the engine up, and then backed it out of the garage by starting it in reverse. Took some pictures of it, and then started it up, and drove it around in a circle in the yard, and back into the garage. Got it close in the garage where I wanted it, and then pulled the coil wire, and just used the starter to move it.
As you can see, I have a lot of body work to do on this truck. Right now. I am just concentrating on getting it running. Well, it runs, but it does not have any brakes in it. After the kingpin job, I just put the front wheel hubs on, and the brake drums, no brake internal parts. Tires just to hold it off the ground, so I could take some pictures of it. After the pictures, back into the garage, and up on blocks.
I pulled all the wheel cylinders out of the truck. I pulled both the clutch and brake master cylinder out of the truck. I then scavenged brake and clutch master cylinders from my other two PL-521 pick ups I have. I also took eight of the ten brake drums I have to Clackamas auto parts and had the drum inner diameter checked. I had three stock sized drums, with minor scoring, and two other drums .020 oversized. Three were .040 o/s, I will maybe just save those for later.
I have three old brake master cylinders, two old clutch master cylinders, two old 3/4 rear wheel cylinders, two old 13/16 rear wheel cylinders, and three old 13/16 front wheel cylinders. Two of the front wheel cylinders are missing the nuts and washers to hold them on the brake back plate. I also found a set of front brake shoes, new in the box, and a set of lightly used rear brake shoes, i also have many old and worn brake shoes, front and rear. Maybe I will put some used, but serviceable brake shoes in the wheels and run them for a while, until I know the wheel cylinders rebuilt without leaks.
Scrounging around for the brake parts, I found the rubber pieces for the side marker lights I was missing. I also found several knobs for the dashboard controls, I might have two complete sets, wiper/wash, lights, heater fan, choke, hazard flasher, and maybe even cigarette lighter.
While waiting for brake parts to come in, I found a good emergency brake cable to replace the worn one on the truck. The one on the truck is serviceable, but has a few strands frayed on it. The good cable got cleaned yesterday, and I hung it up in the garage so and solvent would run out of it. I am going to grease it, and put the good one on the truck. Only one side of the bad cable was frayed, I might have a useable half on the parts truck I have.
Clackamas Community College has an automotive program, and they offer several classes for the "hobbyist" auto person. Street Rod construstion, Auto Restoration, Collision Repair Refinishing, Air Brush Art, Basic Automotive Pinstriping. Many of the classes are offered on evenings, or Saturdays. I did get registered for one of the restoration classes on Saturday. The Datsun is going to be my project.
This is a picture of the truck I have been robbing some parts from. Maybe some day I will get this one running, too.
I pulled all the wheel cylinders out of the truck. I pulled both the clutch and brake master cylinder out of the truck. I then scavenged brake and clutch master cylinders from my other two PL-521 pick ups I have. I also took eight of the ten brake drums I have to Clackamas auto parts and had the drum inner diameter checked. I had three stock sized drums, with minor scoring, and two other drums .020 oversized. Three were .040 o/s, I will maybe just save those for later.
I have three old brake master cylinders, two old clutch master cylinders, two old 3/4 rear wheel cylinders, two old 13/16 rear wheel cylinders, and three old 13/16 front wheel cylinders. Two of the front wheel cylinders are missing the nuts and washers to hold them on the brake back plate. I also found a set of front brake shoes, new in the box, and a set of lightly used rear brake shoes, i also have many old and worn brake shoes, front and rear. Maybe I will put some used, but serviceable brake shoes in the wheels and run them for a while, until I know the wheel cylinders rebuilt without leaks.
Scrounging around for the brake parts, I found the rubber pieces for the side marker lights I was missing. I also found several knobs for the dashboard controls, I might have two complete sets, wiper/wash, lights, heater fan, choke, hazard flasher, and maybe even cigarette lighter.
While waiting for brake parts to come in, I found a good emergency brake cable to replace the worn one on the truck. The one on the truck is serviceable, but has a few strands frayed on it. The good cable got cleaned yesterday, and I hung it up in the garage so and solvent would run out of it. I am going to grease it, and put the good one on the truck. Only one side of the bad cable was frayed, I might have a useable half on the parts truck I have.
Clackamas Community College has an automotive program, and they offer several classes for the "hobbyist" auto person. Street Rod construstion, Auto Restoration, Collision Repair Refinishing, Air Brush Art, Basic Automotive Pinstriping. Many of the classes are offered on evenings, or Saturdays. I did get registered for one of the restoration classes on Saturday. The Datsun is going to be my project.
This is a picture of the truck I have been robbing some parts from. Maybe some day I will get this one running, too.
Today some brake parts I ordered came in, and a clutch master cylinder kit. I cleaned up the three brake master cylinders, two clutch master cylinders, and the wheel cylinders I have. The two clutch master cylinders looked good, and rebuildable. One brake master cylinder looks rebuildable, one is maybe ok, and one is junk. The junk one will be my core, if I ever need one, or maybe it goes into my aluminium recycling pile.
I did not use a conventional hone for the cylinders. I took about a 18 inch long piece of gas welding rod, and bent a sharp bend, about one inch in one end of it, right back on itself. I then bent the remaining rod about in the middle, back on itself again. The rod now has three pieces of rod on one end, and a closed loop on the other end. I then got a piece of Scotchbrite pad, stuck it in the loop in the welding rod, and wrapped the Scotchbrite pad piece around the welding rod. The other end of the bent welding was chucked in a drill, and now, a cheap brake cylinder hone. If you use a fine grade of the Scotchbrite pad, it does a good job of cleaning and polishing the inner bore of wheel and master cylinders.
The clutch master cylinder got rebuilt, and I just cleaned up the slave cylinder. put them back on the truck, bled them, and I now have a working clutch. The master cylinder kit is available from Raybestos, #CMK554. Price, around $20.00, this kit includes a new metal piston, with the rubber cups already installed on the piston.
The two 13/16 rear wheel cylinders I had were bad. The two 3/4 rear cylinders looked good, and cleaned up nicely. I ordered two 3/4 rear wheel cylinder rebuild kits.
After starting to put the 3/4 inch wheel cylinders back together, I noticed that one of the 3/4 wheel cylinders was actually 13/16 inch. It was marked 3/4. I guess I am not going to get the rear wheel brakes put together tonight.
I did not use a conventional hone for the cylinders. I took about a 18 inch long piece of gas welding rod, and bent a sharp bend, about one inch in one end of it, right back on itself. I then bent the remaining rod about in the middle, back on itself again. The rod now has three pieces of rod on one end, and a closed loop on the other end. I then got a piece of Scotchbrite pad, stuck it in the loop in the welding rod, and wrapped the Scotchbrite pad piece around the welding rod. The other end of the bent welding was chucked in a drill, and now, a cheap brake cylinder hone. If you use a fine grade of the Scotchbrite pad, it does a good job of cleaning and polishing the inner bore of wheel and master cylinders.
The clutch master cylinder got rebuilt, and I just cleaned up the slave cylinder. put them back on the truck, bled them, and I now have a working clutch. The master cylinder kit is available from Raybestos, #CMK554. Price, around $20.00, this kit includes a new metal piston, with the rubber cups already installed on the piston.
The two 13/16 rear wheel cylinders I had were bad. The two 3/4 rear cylinders looked good, and cleaned up nicely. I ordered two 3/4 rear wheel cylinder rebuild kits.
After starting to put the 3/4 inch wheel cylinders back together, I noticed that one of the 3/4 wheel cylinders was actually 13/16 inch. It was marked 3/4. I guess I am not going to get the rear wheel brakes put together tonight.
The last few days, I did one of my most favorite vehicle maintaince jobs, while waiting for brake parts I ordered to come in. Repack the front wheel bearings. Items I needed, a seal for each wheel, two cotter pins, size 5/32 x 1 1/2, and bearing grease. The seal is a Timkin 1977 seal, and the grease I used is is Valvoline Ford-Lincoln-Mercury moly fortified multipurpose grease, Valvoline part number W632. If you know what kind of grease is in your hubs, get that grease. Some aerosol brake cleaner is nice to have, too.
It is also nice to have some thin nitrile gloves, and some popsicle sticks, and a roll of paper towels
Keep the two sides seperate if you are doing both sides, at the same time.
Take the dust cap off by gently tapping around the gap between it and the wheel hub with a cold chisel. Remove the cotter pin, and take the big nut off. Pull the hub straight off, and then pry the old seal from the back of the hub with a large screwdriver.
Now, clean everything. Use the popsicle stick to dig a lot of the old grease out of the hub. If you are changing from an unknown grease you need to clean it all out. A solvent tank is very useful, but it can be done in a old large can, with a cheap paint brush, with mineral spirits. Clean out the hubs, and set then aside to dry. Clean the bearings, and set them aside to dry. Clean all the other parts. Do not forget to clean the spindles still on the truck. Spray down everything with the brake cleaner, and let it dry again.
Now, time to start packing grease. Put some clean gloves on. Get a clean popsicle stick. Pack the space between the bearing races in the hub, with grease, leaving a hole for the spindle to pass through. Put a layer of grease on the spindle. Put the hub down on something clean, small end down. Put some grease in the dust cap, around the edges, and make a conical depression in the grease, in the cap.
Put a large tablespoon sized blob of grease in the palm of your hand. Hold the bearing in the other hand, narrow side up. Push the open side of the bearing race into the edge of the grease in the palm of your hand, taking small bites of the blob of grease. After doing this a few, or several times, you should see grease start coming through the bearing. Work your way all around the bearing. When the bearing has grease all the way around, you can put the small bearing down, on something clean. You can carefully set the large bearing in the hub. After the bearings and hub are packed, you can take off the gloves again.
On my 521 there was a thin spacer that sat between the large bearing outer race, and the grease seal. Put that spacer in, if you have one. Push the seal in. Try to start it straight, and evenly push it in. My seals went in with firm pressure, with my thumbs.
Slide the hub straight on the spindle. Slide the small bearing on the spindle, and push it into the hub. Some grease should ooze out as the small bearing slides into place. Put the large washer with the tab that fits into the slot of the spindle, on the spindle, and then the nut.
Now, set the preload on the bearings. Tighten the nut to 23 to 24.5 foot-pounds of torque. Spin the hub many times, forward and back. Re-torque the nut, and spin the hub again. Keep torqueing the nut and spinning the hub until the torque stays the same on the spindle nut. Back the nut 40 to 70 degrees, until the cotterpin holes in the spindle line up with a space in the nut. Put the cotter pin in. Spread the ends of the cotter pin, and make sure they are close to the nut, and put the dust cap back on. You can use the cold chisel to tap around the edges of the cap to drive it on all the way.
It is also nice to have some thin nitrile gloves, and some popsicle sticks, and a roll of paper towels
Keep the two sides seperate if you are doing both sides, at the same time.
Take the dust cap off by gently tapping around the gap between it and the wheel hub with a cold chisel. Remove the cotter pin, and take the big nut off. Pull the hub straight off, and then pry the old seal from the back of the hub with a large screwdriver.
Now, clean everything. Use the popsicle stick to dig a lot of the old grease out of the hub. If you are changing from an unknown grease you need to clean it all out. A solvent tank is very useful, but it can be done in a old large can, with a cheap paint brush, with mineral spirits. Clean out the hubs, and set then aside to dry. Clean the bearings, and set them aside to dry. Clean all the other parts. Do not forget to clean the spindles still on the truck. Spray down everything with the brake cleaner, and let it dry again.
Now, time to start packing grease. Put some clean gloves on. Get a clean popsicle stick. Pack the space between the bearing races in the hub, with grease, leaving a hole for the spindle to pass through. Put a layer of grease on the spindle. Put the hub down on something clean, small end down. Put some grease in the dust cap, around the edges, and make a conical depression in the grease, in the cap.
Put a large tablespoon sized blob of grease in the palm of your hand. Hold the bearing in the other hand, narrow side up. Push the open side of the bearing race into the edge of the grease in the palm of your hand, taking small bites of the blob of grease. After doing this a few, or several times, you should see grease start coming through the bearing. Work your way all around the bearing. When the bearing has grease all the way around, you can put the small bearing down, on something clean. You can carefully set the large bearing in the hub. After the bearings and hub are packed, you can take off the gloves again.
On my 521 there was a thin spacer that sat between the large bearing outer race, and the grease seal. Put that spacer in, if you have one. Push the seal in. Try to start it straight, and evenly push it in. My seals went in with firm pressure, with my thumbs.
Slide the hub straight on the spindle. Slide the small bearing on the spindle, and push it into the hub. Some grease should ooze out as the small bearing slides into place. Put the large washer with the tab that fits into the slot of the spindle, on the spindle, and then the nut.
Now, set the preload on the bearings. Tighten the nut to 23 to 24.5 foot-pounds of torque. Spin the hub many times, forward and back. Re-torque the nut, and spin the hub again. Keep torqueing the nut and spinning the hub until the torque stays the same on the spindle nut. Back the nut 40 to 70 degrees, until the cotterpin holes in the spindle line up with a space in the nut. Put the cotter pin in. Spread the ends of the cotter pin, and make sure they are close to the nut, and put the dust cap back on. You can use the cold chisel to tap around the edges of the cap to drive it on all the way.
I am still waiting for brake parts, but there is plenty of other stuff to work on. Horn, cabin light, windshield washer, the heater was not hooked up to start the engine, the fuel gauge was not reading correctly.
I removed the heater, and found a crack in the top tube of the heater, from water freezing in it. I then found my two other heaters I have left over from other Datsun pickups, and pulled the heater cores out of them. On Monday, they get taken to my friendly neighborhood radiator shop, and pressure tested. I checked the motors in all three heaters, and chose the best one for a core when I find a good one.
The windshield washer was the next item I worked on. I had two that I found, and both of them did not run when I hooked them up to the battery, directly. I took the motor out of the bottom of the bag, and took the back plate off the pump, turned the impeller by hand, cleaned up the pump with a detail brush, and got both motors working again.
I found a total of seven horns. Two worked, five did not. I was able to take the horns apart, clean the contacts inside of them, and I got six of seven working. by hooking the horns up directly to a battery. They did not work in the truck, with the horn lever pushed. I pulled the horn ring off the steering wheel, and pulled the steering wheel. There is a springy wiper behind the steering wheel that makes contact with a ring on the back of the steering wheel, that attached to a spring that pushes almost to contact on the back of the horn ring. Long story short, it took a couple of tries to find out where the contact was being lost in all the connections for the horn ring.
The cabin light was easy to fix. Power always goes to the cabin light, and the switch on the light just grounds the light, and it comes on. I took a small piece of very fine sandpaper, and cleaned the contacts, and now the cabin light works.
I sorted out the connections for the combination meter plug, by looking at a schematic, trial and error, and reading that section of my service manuals
Both the fuel gauge, and the water temp gauge work the same way. When the key is on, power is applied to pin #8 in the ten pin plug on the back of the combination meter. Pin #4 goes to the gas tank sender, pin #12 goes to the temp sender on the motor. Grounding pin #4 causes the gas gauge to go to full, according to my service manual, a 35 ohm resistor should cause this gauge to read half. Grounding pin#12 causes the temp gauge to go to full, (hot) and a 40 ohm resistor should cause the gauge to read normal.
Tomorrow, I plan on going to Radio Shack, and seeing if I can get the two resistors I need to check the two gauges on the combination meter.
I am going to try to see if I can make a diagram of the pins on the back of the combination meter, and post it soon.
I removed the heater, and found a crack in the top tube of the heater, from water freezing in it. I then found my two other heaters I have left over from other Datsun pickups, and pulled the heater cores out of them. On Monday, they get taken to my friendly neighborhood radiator shop, and pressure tested. I checked the motors in all three heaters, and chose the best one for a core when I find a good one.
The windshield washer was the next item I worked on. I had two that I found, and both of them did not run when I hooked them up to the battery, directly. I took the motor out of the bottom of the bag, and took the back plate off the pump, turned the impeller by hand, cleaned up the pump with a detail brush, and got both motors working again.
I found a total of seven horns. Two worked, five did not. I was able to take the horns apart, clean the contacts inside of them, and I got six of seven working. by hooking the horns up directly to a battery. They did not work in the truck, with the horn lever pushed. I pulled the horn ring off the steering wheel, and pulled the steering wheel. There is a springy wiper behind the steering wheel that makes contact with a ring on the back of the steering wheel, that attached to a spring that pushes almost to contact on the back of the horn ring. Long story short, it took a couple of tries to find out where the contact was being lost in all the connections for the horn ring.
The cabin light was easy to fix. Power always goes to the cabin light, and the switch on the light just grounds the light, and it comes on. I took a small piece of very fine sandpaper, and cleaned the contacts, and now the cabin light works.
I sorted out the connections for the combination meter plug, by looking at a schematic, trial and error, and reading that section of my service manuals
Both the fuel gauge, and the water temp gauge work the same way. When the key is on, power is applied to pin #8 in the ten pin plug on the back of the combination meter. Pin #4 goes to the gas tank sender, pin #12 goes to the temp sender on the motor. Grounding pin #4 causes the gas gauge to go to full, according to my service manual, a 35 ohm resistor should cause this gauge to read half. Grounding pin#12 causes the temp gauge to go to full, (hot) and a 40 ohm resistor should cause the gauge to read normal.
Tomorrow, I plan on going to Radio Shack, and seeing if I can get the two resistors I need to check the two gauges on the combination meter.
I am going to try to see if I can make a diagram of the pins on the back of the combination meter, and post it soon.
Sorry, I have not yet got a diagram of the plug for the combination meter. I have been too tired to figure out a drawing program I like.
Since my last post, I have got brake parts in, and I have the rear brakes back together. I am working on the front brakes on the day this was written. It seems that every thing I want to reuse has a layrt of rust I have to clean off any part. It would be easier, to just buy new, but some of the parts are not available, or if they were, I would have to stop work to get them.
My cabin light, and cigarette lighter electric feed quit working, they worked last month. Long story short, a plug on the cab wire harness, that connects to the engine room harness had some corrosion in it, and I tried to clean it, and after taking it apart, and putting it back together a few times, it seems to be working again.
A Datsun PL-521 has three wiring harnesses. A rear harness, a cab harness, and the engine room harness. The rear harness is for the rear lights, and the sender for the fuel gauge. Here is the color code:
Yellow wire Fuel gauge sender
Red with Black wire Reverse light switch on transmission.
Green with yellow Brake lights
Red with blue wire Tail lights, Side marker lights, Licence plate light
White with red wire Left turn signal
White with Black Right turn signal
The red with black wire stops at a connector by the reverse switch on the transmission. It then continues back, still red with black to the single connector by the three pin taillight connector. The single connector is for the back up lights.
The four pin connector is for the neutral, and third gear switch on the transmission. These switches are part of a pollution control system used on these trucks.
1/4 female spade connectors will plug into the six wires on the six pin plug.
The rear harness plugs into the engine room harness by the starter. There are two plugs, the six pin plug, and a four pin plug.
The cab harness plugs into the engine room harness underneath the dash board, on the right side of the glovebox, there are several plugs there. one of the smaller six pin plugs was the problem with my cabin light. The engine room harness goes through a hole in the cab firewall, through a grommet. the cab harness goes to the left near the top of the dashboard, plugs into the switches on the dashboard, plugs into the turn, and the hazard flasher, plugs into the brake light switch, the clutch switch, and into the ignition switch. Ther is one wire that goes into the cab by the drivers side door, and goes up to the cabin light. This wire should be hot all the time. The cab harness also has one small leg that goes back out into the engine room through another firewall hole, right by the hole thar the engine room harness come through. This goes to the windshield wiper motor, right by the fuse box.
the engine room harness has two legs that go around the engine room on both sides.
My light, heater, and wiper switch were hard to move, and sometimes the washer part of the wiper switch stayed on. I pulled the switches out of the dashboard, and cleaned them as best I could. One I got the switch out of the dashboard, I sprayed some WD-40 on the shaft, while holding the shaft up. so the WD-40 would run down into the switch. I then would work the switch several times, occasionally wiping black crud off the shaft of the switch. I them repeated the process, if it was necessary to get the switch to work good.
I got the heater cores back, And I think I have two good ones I can use. I need to find an "O" ring for one of the heater valves. I do have one heater working.
My defrost tubes were bad, I was able to find a replacement by buying a generic hot air tube for the intake of an engine. Look for a tube that is 1 1/2 inched in diameter, and 32 inches long. The tube I got folded onto itself, like an accordian and I stretched it out, and cut it into two pieces with a fine tooth hacksaw. The passenger side is shorter, measure one side, cut it and remember to leave yourself enough for the other side.
Details on the brakes soon.
Since my last post, I have got brake parts in, and I have the rear brakes back together. I am working on the front brakes on the day this was written. It seems that every thing I want to reuse has a layrt of rust I have to clean off any part. It would be easier, to just buy new, but some of the parts are not available, or if they were, I would have to stop work to get them.
My cabin light, and cigarette lighter electric feed quit working, they worked last month. Long story short, a plug on the cab wire harness, that connects to the engine room harness had some corrosion in it, and I tried to clean it, and after taking it apart, and putting it back together a few times, it seems to be working again.
A Datsun PL-521 has three wiring harnesses. A rear harness, a cab harness, and the engine room harness. The rear harness is for the rear lights, and the sender for the fuel gauge. Here is the color code:
Yellow wire Fuel gauge sender
Red with Black wire Reverse light switch on transmission.
Green with yellow Brake lights
Red with blue wire Tail lights, Side marker lights, Licence plate light
White with red wire Left turn signal
White with Black Right turn signal
The red with black wire stops at a connector by the reverse switch on the transmission. It then continues back, still red with black to the single connector by the three pin taillight connector. The single connector is for the back up lights.
The four pin connector is for the neutral, and third gear switch on the transmission. These switches are part of a pollution control system used on these trucks.
1/4 female spade connectors will plug into the six wires on the six pin plug.
The rear harness plugs into the engine room harness by the starter. There are two plugs, the six pin plug, and a four pin plug.
The cab harness plugs into the engine room harness underneath the dash board, on the right side of the glovebox, there are several plugs there. one of the smaller six pin plugs was the problem with my cabin light. The engine room harness goes through a hole in the cab firewall, through a grommet. the cab harness goes to the left near the top of the dashboard, plugs into the switches on the dashboard, plugs into the turn, and the hazard flasher, plugs into the brake light switch, the clutch switch, and into the ignition switch. Ther is one wire that goes into the cab by the drivers side door, and goes up to the cabin light. This wire should be hot all the time. The cab harness also has one small leg that goes back out into the engine room through another firewall hole, right by the hole thar the engine room harness come through. This goes to the windshield wiper motor, right by the fuse box.
the engine room harness has two legs that go around the engine room on both sides.
My light, heater, and wiper switch were hard to move, and sometimes the washer part of the wiper switch stayed on. I pulled the switches out of the dashboard, and cleaned them as best I could. One I got the switch out of the dashboard, I sprayed some WD-40 on the shaft, while holding the shaft up. so the WD-40 would run down into the switch. I then would work the switch several times, occasionally wiping black crud off the shaft of the switch. I them repeated the process, if it was necessary to get the switch to work good.
I got the heater cores back, And I think I have two good ones I can use. I need to find an "O" ring for one of the heater valves. I do have one heater working.
My defrost tubes were bad, I was able to find a replacement by buying a generic hot air tube for the intake of an engine. Look for a tube that is 1 1/2 inched in diameter, and 32 inches long. The tube I got folded onto itself, like an accordian and I stretched it out, and cut it into two pieces with a fine tooth hacksaw. The passenger side is shorter, measure one side, cut it and remember to leave yourself enough for the other side.
Details on the brakes soon.
My brakes are basic stock brakes. When I started working on the brakes, I had a total of three master cylinders, four rear wheel cylinders, and two front wheel cylinders to choose from. The master cylinders were too bad to rebuild, the front wheel cylinders were also too bad. Two of the four rear cylinders looked rebuildable.
My front wheel cylinders were 13/16 inch. Two of the rear wheel cylinders were marked 3/4, two were marked 13/16. The two 3/4 wheel cylinders looked rebuildable. I ordered rebuild kits for the rear wheel cylinders. After cleaning the cylinders, and getting the kits, I found out that one of my rear wheel cylinders marked 3/4 was actually 13/16. Cannot use the kits. The kit was a Raybestos WK812.
I then ordered new wheel cylinders for all four wheels. The front wheel cylinders are Raybestos WC 37209, the rear were Raybestos WC 37208.
The brake shoes I used were also Raybestos 406 PG rear, and Raybestos 405 PG front.
The front brake hoses were also bad, Raybestos BH 36737.
The front wheel cylinders went in with no problem. You need to reuse the banjo fitting off your old hose on the new hose.
The brake adjusters have left hand threads on the left side of the truck. This is so you only need to remember to turn the adjustors one way to spread the shoes. Turn the adjustor down to spread the shoes. I spent a lot of time cleaning everything up, and regreaseing the moving parts in the brakes.
When I got the rear wheel cylinders, one would not go on to the brake plate. The boss on the center of the wheel cylinder was not machined centered on the wheel cylinder. I also found out the old nuts for the rear wheel cylinder did not fit, the old cylinder studs were 5/16 x 24 thread, the new wheel cylinders were M8 x 1.25. If you replace your wheel cylinders, get the nuts that fit them, save your self an extra trip to the parts store. I was able to exchange the bad wheel cylinder for a good one, when I picked up the nuts for both wheel cylinders. I think the rear wheel cylinders I got were actually for a 620 truck.
The banjo fitting for one rear wheel cylinder on my truck was not stock. It was brass, and has a different bleeder on it. The standard 3/16 brake line fitting I had did not screw into it. I think somebody switched this one out to a metric size, also.
My rear brake hose looks ok.
I also got two new rear wheel cylinders finally, from the Nissan dealer. The new Nissan wheel cylinders also have the banjo fitting, a new bleeder, and even a nifty little rubber dust cap that goes over the bleeder fitting. I will save them for my next truck.
I think the brakes are functionally the same for the PL-521 trucks, and the earlier 620 truck. I believe you can even use many of the same parts in them.
I think the main difference between the two trucks is that the 620 trucks switched over to using metric sized fastners. I could be wrong on this.
My front wheel cylinders were 13/16 inch. Two of the rear wheel cylinders were marked 3/4, two were marked 13/16. The two 3/4 wheel cylinders looked rebuildable. I ordered rebuild kits for the rear wheel cylinders. After cleaning the cylinders, and getting the kits, I found out that one of my rear wheel cylinders marked 3/4 was actually 13/16. Cannot use the kits. The kit was a Raybestos WK812.
I then ordered new wheel cylinders for all four wheels. The front wheel cylinders are Raybestos WC 37209, the rear were Raybestos WC 37208.
The brake shoes I used were also Raybestos 406 PG rear, and Raybestos 405 PG front.
The front brake hoses were also bad, Raybestos BH 36737.
The front wheel cylinders went in with no problem. You need to reuse the banjo fitting off your old hose on the new hose.
The brake adjusters have left hand threads on the left side of the truck. This is so you only need to remember to turn the adjustors one way to spread the shoes. Turn the adjustor down to spread the shoes. I spent a lot of time cleaning everything up, and regreaseing the moving parts in the brakes.
When I got the rear wheel cylinders, one would not go on to the brake plate. The boss on the center of the wheel cylinder was not machined centered on the wheel cylinder. I also found out the old nuts for the rear wheel cylinder did not fit, the old cylinder studs were 5/16 x 24 thread, the new wheel cylinders were M8 x 1.25. If you replace your wheel cylinders, get the nuts that fit them, save your self an extra trip to the parts store. I was able to exchange the bad wheel cylinder for a good one, when I picked up the nuts for both wheel cylinders. I think the rear wheel cylinders I got were actually for a 620 truck.
The banjo fitting for one rear wheel cylinder on my truck was not stock. It was brass, and has a different bleeder on it. The standard 3/16 brake line fitting I had did not screw into it. I think somebody switched this one out to a metric size, also.
My rear brake hose looks ok.
I also got two new rear wheel cylinders finally, from the Nissan dealer. The new Nissan wheel cylinders also have the banjo fitting, a new bleeder, and even a nifty little rubber dust cap that goes over the bleeder fitting. I will save them for my next truck.
I think the brakes are functionally the same for the PL-521 trucks, and the earlier 620 truck. I believe you can even use many of the same parts in them.
I think the main difference between the two trucks is that the 620 trucks switched over to using metric sized fastners. I could be wrong on this.
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