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'73 620 ignition switch gremlins


Figbuck

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As has been noted by several Ratsunistas, They always run great before they don't anymore.

 

'73 620 standard cab manual tranny: I have kept almost everything stock. New battery reading 12.25 dcv. I was driving around yesterday and parked inside at work so it stayed warm. When I went to leave six hours later, I pressed the accelerator to turn on the choke, turned the key, got dash lights, and a click of relay or relays as usual.

 

No starter. I get my volt meter and see the battery is putting out 12.56 dcv... head lamps are strong, radio, so that is normal.

 

I start to trouble shoot:

 

Power @ fuse block = yes. I pull the female plug on the ignition switch and get 12.27 dcv @ the big white wire = switch funky?

 

I get two pieces of #14awg, peel the ends and hammer them flat for jumpers. I stick one jumper wire into the female plug @ the big white wire that comes from the fuse block to the ignition switch. I put the other end of the jumper wire into the the first wire in the plug that lights the dash up. I stick the other jumper wire in with the first one the hot white wire and touch it to the first clip in the plug that turns the starter...

 

VROOM... engine fires right off... I pull the second jumper out and drive it home with the hot wire stuck in place... get home, pull the wire and kill the engine.

 

This morning I go to leave for work and do the same thing... I get dash lights but the starter will not run. I fuck around with the switch, clean contacts and look stuff over... no starter and no combination of jumper wires cranks it. (starter is only a couple years old and maybe 8Kmi... a $36 re-man that I don't trust... but son of an L block, it's a hunk of metal, not a living thing. It just didn't get sick and die while it was shut off... right?)

 

Now, I'm pissed. I get the PDF from my specific year's wiring diagram. Yes the fat White wire is power from the fuse block. From the Ig. Sw, Black w/Yellow goes to the clip on the Solenoid. The Black w/Red goes to the resistor @ the coil.

 

I know the big white wire is hot, pretty sure that the Black w/Red runs the coil/engine and the Black w/Yellow powers the solenoid and the starter when the key is turned to crank.

 

Now... with the jumper wire in place to the coil, I get little sparks when I try to jump to the Black w/Yellow starter wire, still no cranking.

 

I thought, i should be able to jump directly from the positive battery terminal to the tang on the solenoid where the Black w/Yellow wire from the Ig.Sw is... and get the starter to crank... RIGHT?

 

NO. I do get the same little sparks off of the tang on the solenoid.

 

Could I have fried my solenoid?

 

Is my Ignition switch maybe still good, but the solenoid was not good in the first place... it was a miracle that it worked to get me home?

 

Shouldn't my starter crank if I jump between the lug that the connects the cable from the the battery to the starter... and the clip on the solenoid? That should be the test right?

 

Now I'm home and have no tools they are at work. Should I pull the starter and take it to have it tested? Haven't I tested it?

 

Some where in the back of my mind, I remember 20 or 25 years ago going through this same bullshit where a new $85 Bosch starter only lasted me a month and it was toast. I whacked the solenoid whith a 2x4 and it worked a couple more times before it wouldn't anymore. (I gave this one a good couple of whacks... but that didn't fly.)

 

Help!! this shit drives me crazy, because mostly it is simple stuff... Am I missing something???

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You cannot fry the solenoid by jumping those wires.

 

The most common cause of these symptoms is a dirty battery cable connection. Get both the battery and the cable ends shiny shiny. If the cable ends are bolt-on type, probably they should be replaced.

 

If the ignitiion switch was bad, jumping the wires like you did the first time would work every time.

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New battery. All clean connections, both hot and ground. Shining and slathered with di-electric grease.

 

But... if the solenoid or starter was intermittent and the switch was good then it would act the same and make me think the switch was bad? Bad switch would be my first guess or assumption. A trouble shooting mistake... I never tested the switch.

 

When I jumped it the first time, it cranked hard and fired right off!

 

I should be able to jump from the positive lug on the starter, right from the battery, to the clip on the solenoid and have it spin... right?

 

Why do I get a little sparking when I try to jump the harness or straight the solenoid clip.? That says short to ground to me... no?

 

Like you say, it should work every time.

 

If not, then the solenoid is no good??

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Swtich is not the probelm if jumping it doesn't work.

 

It sparks because it's a lot of current. That's normal.

 

Yes, your solenoid could be bad. Just stick a screwdrive from the larger terminal to the S terminal (don't get it stuck). You can also jump the two large terminals and it should spin, but not engage. And expect a spark.

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A lot of current should make the solenoid engage or click at least. What would be the difference between a screw driver and a piece of #14 wire? Other than conductor size? I don't have any tools here.

 

I just tried again, jumping the battery lug to the starter past the solenoid and it didn't spin either... just sparking.

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Ok... so let's say that the the solenoid is bad. WHY?

 

Why did it just stop working. Why did it work one minute and not the next. Besides shutting the engine off. What is different? What's in a solenoid that "goes bad". I have taken a bunch of crazy stuff apart just to see what was inside, but never a solenoid. It's something like a coil with a shaft running through it right? Pretty simple, not a lot of moving parts. If the contacts were working then it would close the high current circuit and it would spin the starter. So no clicking, i assume that the contacts are... what? Not working... why? Working one minute and fried contacts then next... why?

 

Why can't I make the starter spin when I bypass the solenoid and jump the positive cable to the starter?

 

What am I missing?

 

I'm screwed. I don't have any tools, spare starter, place to work or any money... and unless I walk ten miles to my shop and back, no way to get tools.

 

Maybe I could hot wire to the coil and push start it? Should run right?

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starter wiring has nothing to do with the coil wiring side of things. Even if the wires are disconnectore to the coil. the starter wire should get 12volts when key is switch to On.

 

I would have put a volt meter on the seliniod wire and put key in START and se eif you have 12volts. If you have 12volts it still coule be a low current situation. Here is when people use a HOT START relay.

 

But like others said you can use a screw driver. Crew driver carrys more amps as most starters want alot of CCA.

 

 

also if you use the POS battery cables the have the assembled ends( 2 - 3 pieces) get the molded battery cables.

 

ck your grounds.

 

36dollar starter I would swap out first or wiggle the end at the starter and make sure its tight.

 

I seen one Moron hook up the battey to the ground side of the big lug on the starter instead of the otherside when the positive cable should go.

 

I should be able to jump from the positive lug on the starter, right from the battery, to the clip on the solenoid and have it spin... right? Very true

 

 

I don't have any tools here = buy some

 

Ok... so let's say that the the solenoid is bad. WHY?

Who cares ! they go bad. I dont know why ,cheap parts

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So basically nobody can or will answer my question... if the starter and or solenoid went bad, why? What is there to go wrong?

 

I just looked at my service log. I put in a new starter, alt, radiator and a complete tune 13K two and a half years ago. I replaced the stock starter at around 120K miles and the Bosch I replaced it with lasted close to 200K mi. I guess I could see this starter going out... but why?

 

I got tools out the ass. My pile of tools would probably bury your pile of tools... they ain't here, it's pouring down rain and I have no place to work on it.

 

All the battery cables are clean stock molded connectors. They worked fine. How do they stop working? Like I said, this shit is not alive it doesn't get a virus or disease... it's metal and plastic... how or why does something like that work one second and not the next?

 

I realize that a screwdriver has more capacity to carry current than a piece of wire... but there should still be some kind of continuity. The worst case would be that the wire melts. The head lamps burn bright and the battery is a good one, three months old. I cleaned and greased the cables when I changed it out. For about six years I had a partner who was a CMO/CME for my contracting business. He had the credentials to qualify for an electrical subcontractors license. We made hundreds of thousands of dollars in electrical construction work both private and public work. I have wired everything from little residential remodels to commercial and industrial buildings we built outta the fucking ground. I could have been a good electrician except it is such a boring trade I couldn't stand it. Plus I would have had to have half my brain removed to be content pulling wires and making up boxes all day.

 

I should have thought to put a voltmeter on the solenoid clip... but it cranked hard and caught the first time I jumped it... right? Like you say, even if you got 12vdc on the meter, there could have been a low current situation. So all that tells me is that there is continuity and the battery reads 12vdc.

 

Sorry, I'm really frustrated. So much shit has backfired or blown up in my face recently... truck problems are the last thing I need. All this stuff is not that hard to understand right. That is why we drive these recycled sardine cans, because they are easy to work on.

 

Like you said any moron can figure out how to work a wrench... it's knowledge that is power.

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This is all you need to crank an engine:

CompTest.jpg

The white wire pair goes off to an on/off switch. A total of four wires are needed to crank the engine. Two between the battery, and starter, and block, and two to connect the spade terminal on the starter solenoid to the positive battery cable on the starter.

 

"So basically nobody can or will answer my question... if the starter and or solenoid went bad, why? What is there to go wrong?"

 

You are right about a solenoid. They are just a coil of wire, and a steel slug in them the magnet moves when power is applied.

The wire can break in side of them. The contacts inside it can also go bad, and not make contact when it should.

 

Reality is that very few replacement parts are made with the same quality as the OEM Nissan were made with in the 1970's. Additionally, a lot of the OEM 1970 Datsun stuff can be taken apart, and repaired.

I have actually taken a starter solenoid apart, and cleaned the contacts, and made it work again. I have also carefully drilled out the rivets holding a remote starter solenoid together, and resoldered the coil wire back on to the terminal on the solenoid.

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swap a starter first. see if proplem changes Thats if you have a spare. Most L motor guys always have a spare.

 

as for quility of parts. soem are rebuilds and some are 100% reconditioned. I try to get the one that say 100% but dont know really whats the difference. Some say thy only fix the broke part and just clean the rest as I cant see how they can make a profit on a 36$ starter.

 

If another starter dont do it then i would think its a low current(the key switch is adding to much resisitance) or the lug is not on tight on the small starter wire.

 

Try routing a wire from the Plus side battery to the little blade connectoron the seliniod and that should turn the starter for sure.

 

 

As for the tools, I just laughed.

Most times Datsuns only need a 10, 12 and maybe 14mm and thats more than 80% of the rig. Ok throw in a 17 every now and then.

 

 

the photo on DanialC

The white wire only need to be a few inches and just short it with your hand. Dont need a switch

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I used to have houses, garage full of motorcycles and tools, business with employees that made me money, a big office, shop space, lots of money and time to fuck with the truck or a place to park it until I got time. All that is gone. I have six cents. We live in a cheap apartment that we can't even afford and I'm getting food stamps.

 

For thirty years I carried an old Craftsman tool box packed with two complete sets of sockets, complete set of box end and combination wrenches, special tools I made to get at particular bolts or nuts... and everything to do maintenance on the truck. It fit right behind the wheel well. Some fucks have been breaking into cars on our street and ripped open my camper, breaking the door locks. They didn't take the tool box or two gallon cans of gas! They stole my license plate instead. I haven't been carrying the tool box because I can't lock the camper any more. The other night at the shop, once I got it running, I looked at the tool box, battery charger and other stuff I had been using... and left it all sitting on the bench thinking, I got it to run, now I can get my exhausted ass home after standing on concrete running machines and eating sawdust all day.

 

Skib just PMed me saying that he might be able to rustle up a starter for me. I sweet talked my wife into loaning me her car to go get tools.

 

I know what you are saying about rebuilding OEM parts. One time I was visiting a friend in Sacramento and when I went to leave, had no headlamps. We started testing stuff and traced it to a relay. We drilled the rivets out, cleaned all the crust, soldered all the contact points solid, wrapped it back up and no problems in fifteen years.

 

Oh, Skib called me here. He is going to hook me up with a spare starter... we will see what the deal is.

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the photo on DanialC

The white wire only need to be a few inches and just short it with your hand. Dont need a switch

 

The setup is what I used to test compression. I already had the box, with the switch, and wires. Just had to put a different end on the wires, which I also already had.

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^^^ What ggzilla said, When youve got poor electrical connections/circuits in your ignition wiring it amplifies the problem. It is basically doing the same thing to the inside of your solenoid that arcing a screwdriver does to the posts on the outside of the solenoid, it really doesnt take long to screw one up... and it can be sporadic. ...If you get time pull your solenoid apart from your old starter after you swap the one from Skib.

 

The hot start relay is almost a must have, and its cheap insurance. The relay bypasses most of the problem areas and uses the factory wiring circuit as a trigger. You end up with significantly less heat/resistance going through your switch and ignition wiring. Did you happen to feel the wires on the plug to your ignition switch when you were checking it? They will get hot/melt and if it gets bad enough it will even take out the back of the ignition switch. Also check your fuses/fuseblock. How does the top left one look and does the fuseblock look melted at all?

 

If money is tight, you can do the hot start relay with any bosch style relay from a junkyard (theyre pocket size)... Its not necessary but if you can find one with a mount tab and a plug/harness it will make for a cleaner install and easier wiring.

 

Another thing is that I dont know how many datsuns I have seen in the yards with brand new plugs/wires/starters/battery cables/points/caps... and then I see corroded connections on the fuse block and shitty/missing grounds... Half the time the reciepts are still inside the car...

 

And before I forget, Theyre made from recycled samurai swords... Not tin cans :cool:

 

Good luck man.

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Thanks Jason, I appreciate the offer. :rolleyes:

 

Skib bailed my ass out and drove up to my shop last night to bring me a brand new never used starter. What a prince. :D Had a good time bullshitting with him. I lead a pretty isolated existence. It was great to have somebody to talk to... haven't done that in a coons age.

 

Just put it in and it fired off like a rocket. Good thing. I was dreading having to mess with getting an ignition switch and having to deal with the keys and everything, if that was the culprit. I changed it out in thirteen minutes flat... the apartment manager was giving me the hairy eyeball... :P

 

Mike: I'm going to rip that solenoid apart just to see what is up. It is possible that it got wet and the contacts didn't really like that. I was driving around the industrial district where some of the streets are being torn up for the new street car line and related utility work. It was pouring down rain and I remember driving through a couple big pot holes and flooded areas.

 

The fuse block is fine. Way back when I had the headlight relay problem it melted the original fuse block. I changed it out with a cherry P n' P fuse block and I have a couple other cleans ones I've grabbed too. Unfortunately, I lost my house just as I got the truck got all repainted and put back together. I never got to finish all the upgrade projects that I wanted to do like electronic ignition, ditch the dual points and the Saturn Alt. swap... clean up the wiring, relays, so I could get a decent stereo, fix my cab light, horn and other little stuff that hasn't worked for fifteen years.

 

342K miles and my truck has been 99.9% reliable. I have beat the shit outta it and abused it for 37 years. Skib and I were laughing about how much we like winding the shit out of the little L16s. :lol:

 

I'm sure it will last another 37 years... I probably won't. You live and you learn... I learn something new every day If I'm lucky. I learned something new on this. Wish I hadn't wasted nearly two days to learn it... one of the things that suck about getting old is that you might learn stuff, but you forget that you ever knew it in time.

 

Thanks for the help and moral support everybody.

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