Key won’t engage starter

[Wolfman]

1971 Datsun 510. Went to start my car, cranked once and quit. Battery is good 12.4v. Couldn’t find any loose wires or bad fuses. I can arc the starter with a wrench and it fires up just fine. Lights come on when I turn the key, just won’t engage the started. This has happened before but went away after a few key turns. Do I have a bad ignition switch?

[datzenmike]

 

Does the starter click or chatter when trying to start with the key. Or completely dead.

 

Probably bad but first check the smaller Black/Yellow stripe wire where it connects to the starter. Is it on snug?

[Wolfman]

Completely dead, no clicking. The black and yellow wire is very snug and solid fit.

[Wolfman]

Took apart ignition, with the key on and turning other part with a screw driver I get clicking sounds. Swapper in another one ignition from parts car and same result.

[datzenmike]

 

 

Jumper 12v from the big starter lug to the small one with the Black Yellow stripe. This is essentially what the ignition switch does.

 

1/ If it fails to engage the starter every time then the solenoid on the starter has failed.

 

2/ If the starter engages every time then the ignition switch signal isn't getting through. Borrow a meter and with the Black/Yellow wire off, measure the START signal from the ignition. Long runs of vert old, thin wire to the switch and back to the starter and an old ignition switch can often drop the +12v down below 8 and it's not enough to operate the solenoid properly.  There is a fix for this but I'll wait till you try the above test first. Both of my 710s did this but the starter only chattered in the start position.

[Wolfman]

I’m sorry I’m not sure I follow what you mean, the starter is getting 12v. The yellow/black wire doesn’t get any reading from my volt meter. When I turn the key with everything hooked up it just clicks, but will start if I arc the starter with a wrench or piece of wire 

[datzenmike]

What's clicking the ignition switch or the solenoid on the starter???? It's important.

 

 

 

You measured the disconnected Black/Yellow wire while the ignition switch was in START and got no reading??? Then cut to the chase.... it's the ignition switch.

 

 

[Wolfman]

The clicking noise is coming from the engine bay. I replaced the original ignition with one I had from a parts car. There was no clicking with the original, the sound started after I put in the other one. Still dead yellow and black wire. I guess I’ll order a new one and put it in. Could I just by pass by hooking up a push button to the starter? 

[datzenmike]

Check the voltage on the Black/yellow. Should be battery 12.6 or near. If not the solenoid will sometimes click or chatter. Low voltage can be from a voltage drop from long old thin wire runs.

 

Low voltage on Black/Yellow wire means it needs a hot start relay.

 

If it reads battery then the solenoid on the starter is bad. Try jumping 12v from the positive cable on the starter to the small tab on the solenoid wher ethe Black/Yellow wire was.

[Stoffregen Motorsports]

Isn't the main power for the entire dash fed through the ignition switch? I believe so. Which would also mean that it may or may not pass through the fuse panel first. If it goes straight from batt to switch, then there is a fusible link at the batt and that could be blown.

 

If it clicks but doesn't engage the starter, then the above is not likely the case. It's more likely a bad connection, bad switch or loose ground. Does the motor have a ground to the body and to the battery? That's two grounds. It should have two ground wires.

[datzenmike]

On the 510, everything goes through an in line fusible link, then to the fuse box for things no needed to be switched on by the ignition such as brake lights, lighting, horn, clock etc. and also directly to the ignition which sends [power to the fuse box for things that do need switching such as radio, wipers, heater. The ignition also sends around the fuse box power to the coil, and two start signals, one for the coil and one to operate the starter motor. No matter what everything is still fused.

[Stoffregen Motorsports]

So even the ignition switch power goes through the fuse panel? Fused in the panel? Or does it go straight through the panel without a fuse?

 

Many other vehicles of that era go through the ignition switch first and then to the fuse panel.

 

FWIW - it's not unheard of for a contact in the fuse panel to become loose. The "rivets" that hold them in place wear after decades of rattling and bouncing.

[datzenmike]

There is a fusible link connected to the positive cable at the starter. Everything goes through it to get to the fuse box the alternator and the ignition switch. There is a connection to the volt regulator that isn't fused.

 

Primitive by today's standards.

[banzai510(hainz)]

7 hours ago, Wolfman said:

’m sorry I’m not sure I follow what you mean, the starter is getting 12v. The yellow/black wire doesn’t get any reading from my volt meter

which is it Yes or NO???????????

the black yellow wire what is it getting with a meter? if it getting 11volts or up then the switch is working but if 11v its low. then get a Starter relay set up using a typical black relay for lights. If no voltage at all I would look back by the fuse box.

You get 12volt at the ballast resisitor with KEY ON. if not then ignition fuse or no 12volts there. But you did say you got lights I assume on the dash panel IGN.

 

wiggle the connector behine the key switch. I used to have proplem there also.

 

If you swapped in a ignition switch somebody told me there 2 versions maybe even a 3rd for the earlier 68/69 510s. Make sure they look the same.

 

if you 510 is beat and not worth alot then you could put a bypass in there but I think its hoky and lesson the value of a great car.

 

My 521 is bad on close to this issue. I blow up 10amp fuses which cause NO charging but the IGN light also goes inop. If I didnt have a Cig Lighter volt meter I would never know I had this proplem. Im just running off tha battery and not knowing it till it too late.  My fix was cleing the fuse connection with scotchbrite and squeeze the crimps to make a tighter fit.

Edited July 27 by banzai510(hainz)

[wayno]

Wolfman says it clicks or has clicked which means the solenoid is likely moving, he also says he can start it with a piece of wire, my question would be which wires are you jumping across, from the power supply from the battery to the small exciter wire or to the cable to the motor?

 

I have had problems for several years with solenoids on starters, I call them solenoids China made crap, on my diesel starter I put in a fresh rebuilt starter and it only lasted a week, unfortunately I had had it rebuilt several years before and the guy that did the work retired, but all of my starters have the same issue, after a while they just click, since it takes all day to remove/replace a starter on my 1969 521 kingcab turbodiesel it gets old real quick when they quit working even once a year let alone every month/week, there was nothing wrong with the motors, the solenoid is the issue, so I made a bypass, I connected a battery cable to the starter motor lug, attached it to a relay mounted on the firewall, that relay is wired directly to the battery, I put a button on my dash to activate the relay, when I turn the key to start it if nothing happens I push the button and it starts turning over right away, sometimes I even let off the button and the starter continues turning over until the engine starts, I have never had an issue since doing this.

 

Keep in mind that I was willing go this far because I cannot even see the starter unless I have a flashlight to peek thru small gaps, there is no room anywhere for anything else in my engine compartment, the relay/cables are visible in this photo.

 

 

My issues are not wiring/switch/battery issues, my issue is the plates that touch each other inside the solenoid that give power to the power motor, once I get it turning over, I normally keep pressing the bypass button until the engine starts but I was curious if it would continue to turn over if while the key was in the start position if I let off the button and it has every time so far(less than 10 times over a few years now(3 or 4 years?), I also had this same issue with my 1971 Datsun 521 work truck years ago, an older L block OEM starter fixed it that time, but that one was easy to remove/replace.

[datzenmike]

On 7/27/2024 at 2:07 PM, banzai510(hainz) said:

which is it Yes or NO???????????

 

 

People know what they mean but I'm no mind reader. I ask a simple question: Is the left or right side brake shoes dragging? and  get: yes, or yes one side gets hot. SMH

[Stoffregen Motorsports]

16 hours ago, wayno said:

 

 

I have had problems for several years with solenoids on starters, I call them solenoids China made crap, on my diesel starter I put in a fresh rebuilt starter and it only lasted a week, unfortunately I had had it rebuilt several years before and the guy that did the work retired, but all of my starters have the same issue, after a while they just click, since it takes all day to remove/replace a starter on my 1969 521 kingcab turbodiesel it gets old real quick when they quit working even once a year let alone every month/week, there was nothing wrong with the motors, the solenoid is the issue, so I made a bypass, I connected a battery cable to the starter motor lug, attached it to a relay mounted on the firewall, that relay is wired directly to the battery, I put a button on my dash to activate the relay, when I turn the key to start it if nothing happens I push the button and it starts turning over right away, sometimes I even let off the button and the starter continues turning over until the engine starts, I have never had an issue since doing this.

 

 

I know what you mean. It's a thing I used to do on all my Datsuns. I'd make a jumper wire to go from the battery side of the solenoid to the solenoid terminal, then install a Ford starter relay/solenoid which is hot on one side and goes to the starter on the other side. For some reason the Ford type setup works more consistently than the solenoid mounted on the starter. Maybe it's heat, maybe it's vibration, heck it could be the oil and grime that gets a starter dirty. Who knows? But the externally mounted relay always does the trick.

 

 

 

[Icehouse]

I had an ignition in one of my 510's you you had to lift up on the key while turning it.  It was a 68 ignition.  Sometimes the later ones you gotta go slow when it gets to the crank position.  You can skip past the contact.  

[iceman510]

Make sure the battery cables are clean too,  You can get an attempt to start, but not enough current to power the engine spinning over.