Car won't shut off with key.

[thumper]

Hey Guys,

 

I am having a weird problem with my 510. It does not shut off when I turn the key off. The motor will stay running.

 

I thought it might of had to do with my ignition since my old one was worn and key comes out in any position. I replaced it with a new ignition.

 

I also installed a adjustable fpr yesterday and have fuel set to 3.5 psi.

 

Any one have any idea on what I can check that would allow car to keep running after I remove the key?

 

Thanks,

[datzenmike]

Have you replaced anything else lately? Like a voltage regulator?

[thumper]

The voltage regulator was replaced not too long ago.

 

I was also reading how the voltage regulator can cause the temp gauge to not work. My temp gauge does not work. It stopped working one day. I did not realize if it was the same time I changed the voltage regulator.

[thumper]

I should still have my old one I can swap back. I had one that was brand new in the car when I bought it. So I put it in.

[datzenmike]

I meant to say alternator not regulator.... but try that.

[thumper]

Oh ok. Alternator is the same as it always been.

 

Other issues. Car does not crank on key. Right now I have the starter hooked up to a push button. These problems would be intermittent. Now they won't work at all.

 

I have a switch for the fuel pump. When I turn the fuel pump off. Fuel pressure goes down to zero on the fpr gauge. But the motor would stay running. Take the key out still runs.

 

Could it be a bad ground somewhere. Not sure if a bad ground would cause these symptoms.

 

Thanks

[banzai510(hainz)]

If you have a external volt reg. put key to off then unplg the volt reg on the strut tower. It should stop !

 

 

the dash gas gauge/temp gauge has a volt reg on the dash inside. its different.

[thumper]

If you have a external volt reg. put key to off then unplg the volt reg on the strut tower. It should stop !

 

 

the dash gas gauge/temp gauge has a volt reg on the dash inside. its different.

 

That is how I shut it off now. But I pull the fuse box plug. I would like to fix the problem thought and get it to shut off on key.

 

I can check the one on the dash. The fuel works but temp does not.

[haubstr]

Wow - are you sure you don't have my car? I have been dealing with the same exact problems with my 510 for about 4 years. I just learned to work around it. I would really like to fix it though.

 

I have a push button start because it doesn't crank with the key. It started off intermittent and then it stopped starting with the key altogether. Occasionally I will have the problem of turning off the key and continue to run. I just put in gear and let out the clutch with the brake on to kill it.

 

I have a Z alternator with internal regulator, MSD 6A box, Pertronix, electric fuel pump w/On-Off toggle switch, and SU's. Just throwing that out there to see if we have any common factors to narrow it down.

 

Let me know what you come with or if you want me to try anything on my end

[banzai510(hainz)]

Thumper

So you bought a new volt reg????? and tryed it out???? Right now that shows its the volt reg. Thats the usual fix as of right now.

 

 

haubstr

I have a push button start because it doesn't crank with the key. It started off intermittent and then it stopped starting with the key altogether.

 

you ck for 12volt at starter wire???????? then ck at back of key switch.??????

[doomdatsun]

I have a push button start because it doesn't crank with the key. It started off intermittent and then it stopped starting with the key altogether. Occasionally I will have the problem of turning off the key and continue to run. I just put in gear and let out the clutch with the brake on to kill it.

 

 

maybe you have a wire that has been burnt or damaged because of high current, it would make contact a couple of times, but the excessive heat would destroy it, check the ignition circuit wiring with a multimeter on the ohms scale and see of there is connection.

one more thing to check is the anti deiseling selnoid if its working

[haubstr]

Thanks Hainz and Doom for the replies. When it first started doing this I did a quick check but haven't really dug into it since then. I have class after work today, but tomorrow I'll be all up in it.

 

I'll let you know results

 

Thanks again

[datsunaholic]

90% of the time, it's a faulty voltage regulator. It self powers the ignition circuit, causing a relay loop. I've had the problem twice with 2 different Datsuns and both times it was the regulator.

 

AND... even though the gauges have their own regulator, when my '72 510's temp AND fuel gauges started acting up, replacing the main voltage regulator solved it. Odd but true. If only ONE gauge acts up, it's not the regulator since it controls both.

[thumper]

Wow - are you sure you don't have my car? I have been dealing with the same exact problems with my 510 for about 4 years. I just learned to work around it. I would really like to fix it though.

 

I have a push button start because it doesn't crank with the key. It started off intermittent and then it stopped starting with the key altogether. Occasionally I will have the problem of turning off the key and continue to run. I just put in gear and let out the clutch with the brake on to kill it.

 

I have a Z alternator with internal regulator, MSD 6A box, Pertronix, electric fuel pump w/On-Off toggle switch, and SU's. Just throwing that out there to see if we have any common factors to narrow it down.

 

Let me know what you come with or if you want me to try anything on my end

 

Things we have in common are electric fuel pump w/On-Off toggle switch and I have webers.

[thumper]

90% of the time, it's a faulty voltage regulator. It self powers the ignition circuit, causing a relay loop. I've had the problem twice with 2 different Datsuns and both times it was the regulator.

 

AND... even though the gauges have their own regulator, when my '72 510's temp AND fuel gauges started acting up, replacing the main voltage regulator solved it. Odd but true. If only ONE gauge acts up, it's not the regulator since it controls both.

 

I am going to switch back to my old regulator when I get home and see what happens. Hopefully that fixes a few of these issues.

 

Thanks

 

Thumper

So you bought a new volt reg????? and tryed it out???? Right now that shows its the volt reg. Thats the usual fix as of right now.

 

 

haubstr

I have a push button start because it doesn't crank with the key. It started off intermittent and then it stopped starting with the key altogether.

 

you ck for 12volt at starter wire???????? then ck at back of key switch.??????

 

Hainz, I will check for 12 volt at the key switch when I get home. I have 12 volts at the solenoid. It could be a break in the wire.

 

Thanks

[doomdatsun]

guys could it be possible that even though the voltage regulator wiring harness have same code as the original but different in connection underneath?

[banzai510(hainz)]

Hainz, I will check for 12 volt at the key switch when I get home. I have 12 volts at the solenoid. It could be a break in the wire.

 

Thanks

 

That part of the reply is for Haubstr,

Thumper Im sure your fine in the starting dept.

[Dat Lurka]

What carb??

MY Hitachi has an Anti-Dieseling Solenoid. When I got my truck it wouldn't turn off. I found that the wire was broken right at the solenoid. Soldered it back and haven't had a problem since.

[datsunaholic]

Even without a functional AD solenoid, cutting the ignition should shut off the engine. The AD solenoid simply cuts off the idle so that the engine doesn't "diesel", or compression/glow ignite. There's a big difference between dieseling and simply not shutting off. Datsuns didn't have anti-dieseling solenoids until 1973 in most cases, though some had them before. My '72 510 didn't have one and doesn't have the wiring for it, though the carb I have does, so I just hooked it and the electric choke together,

[thumper]

Hainz, I will check for 12 volt at the key switch when I get home. I have 12 volts at the solenoid. It could be a break in the wire.

 

Thanks

 

That part of the reply is for Haubstr,

Thumper Im sure your fine in the starting dept.

 

Hainz, I am having the same problem and am using a push button as well to start. =(

 

Seems like me and Haubstr are having the exact same symptoms. Lol

[thumper]

I switched out my voltage regulator with the old one yesterday. Now my car turns off by itself. so that issue is fixed.

 

Just need to work on the rest. Something that was odd. Was when I switched the VR. It also fixed my horn and brakes. Which I thought was a horn relay as I dont see the voltage regulator hoing to the Horn relay on the wiring diagram.

 

Then I took it out for a drive all was well and then my horn stopped working.

 

Issues I still have.

 

- Does not start on key. ( i need to check 12 volt at key)

- water temp gauge does not work. Fuel does. ( i need to check VR in cluster. )

- Horn relay does not work.

- rear reverse lights do not work.

 

Going to go home and work on it in a bit.

[datsunaholic]

The cluster VR operated both the temp and fuel gauges. More commonly the temperature sender is corroded. Pull the wire and ground it to the engine, the gauge should peg "H". If it doesn't then the gauge or wiring has issues, if it does then the sender is corroded or failed. Sometimes just cleaning the terminal makes it work.

[banzai510(hainz)]

- Horn relay does not work. ??????

 

if horn dont work then the brakes light dont work in most cases.

If brake light works then of cuase the fuse is good at least up to that point

 

Horn will ground on the steering wheel and I think there is a plug or connection you can ck from there using a ohm meter. put ohm meter on and hit the horn and see if you get a short.

[thumper]

- Horn relay does not work. ??????

 

if horn dont work then the brakes light dont work in most cases.

If brake light works then of cuase the fuse is good at least up to that point

 

Horn will ground on the steering wheel and I think there is a plug or connection you can ck from there using a ohm meter. put ohm meter on and hit the horn and see if you get a short.

 

I am thinking it is the horn relay that is bad. brake lights and horn does not work. It has been working off and on.

[thumper]

The cluster VR operated both the temp and fuel gauges. More commonly the temperature sender is corroded. Pull the wire and ground it to the engine, the gauge should peg "H". If it doesn't then the gauge or wiring has issues, if it does then the sender is corroded or failed. Sometimes just cleaning the terminal makes it work.

 

I was thinking the sender was bad. Takes 1 week to order a new one locally here. I did not have time to order it yet.

 

I will clean the terminal when I get home and ground it and see what happens.

 

Thanks