510 dash gremlin ?

[Bob3]

Here is my Gremlin;

 

My 1968 510 2 door sat in a yard for 15 years. I got it running (fresh L20b). The gas tank was very clean and the first time I put gas in it and turned on the key on, the gauge worked as it should. I hooked up the stock temp gauge wire to the engine and it worked as it should. While I'm out driving it now and both gauges will drop at the same time as if the power is unplugged. They won't drop off all the way down, I'd say they go down 80% and flick up and down some then a while later they just go back up and function normally. It seems like a ground problem to me, but where?

 

It seems like it is not working 90% of the time I'm driving it.

 

 

What do you experts think?

[Shagy]

Check your grounds. @ the dealer we've had cars with poor grounds exhibit smilar issues.

[philcas1987]

Dash ground is above driver kick panel. Check the round plug and pins that go into the instrument cluster. Atom had a few pins Broken. Brittle. Worth a shot

[datzenmike]

I don't think it a ground. Power passes through a voltage regulator then to the two gauges, and from the gauge to the temp or fuel level sender and to ground. The regulator holds the voltage at a reasonably steady 8 volts. This steady 8 volts prevents the gauge changing from 12 volt idle (headlights on) to 14.5 volt cruise speed. The fact that both gauges are affected tell me it may be the common voltage regulator in the back of the gauge cluster.

[MikeRL411]

I don't think it a ground. Power passes through a voltage regulator then to the two gauges, and from the gauge to the temp or fuel level sender and to ground. The regulator holds the voltage at a reasonably steady 8 volts. This steady 8 volts prevents the gauge changing from 12 volt idle (headlights on) to 14.5 volt cruise speed. The fact that both gauges are affected tell me it may be the common voltage regulator in the back of the gauge cluster.

I agree. It is most likely the instrument panel Voltage Regulator.

[Bob3]

Great - so the instrument panel has a voltage regulator. That sounds like the culprit. That makes sense to me since it kind of pulses towards the bottom of the throw, it does not go dead.

 

Where do I get one for a '68?

 

I'm excited!

[datzenmike]

Great - so the instrument panel has a voltage regulator. That sounds like the culprit. Where do I get one for a '68?

 

I'm excited!

 

Because of the similarity of all gas tank senders and temp senders it's likely that all regulators are the same for the 510. It may be a plug in item on the back of the cluster... I think the 521 is that way. Might even be the same.

 

25020 13200 is the part number from Nissan, about $15. It's located on the back of the instrument cluster on the right side and is rectangular in shape.

[frodo70444]

clearly you have a ghost in your car dont worry i own two cars with ghost in them the headlights in my datsun randomly turn on then when i go outside at 3-4 am to turn them off i get 5 feet from the car and they just go off and i was driving a family hand me down olds that will randomly die randomly not start randomly backfire sometimes it would act fine for months sometime it wouldnt act right for two days in a row

[MikeRL411]

Because of the similarity of all gas tank senders and temp senders it's likely that all regulators are the same for the 510. It may be a plug in item on the back of the cluster... I think the 521 is that way. Might even be the same.

 

25020 13200 is the part number from Nissan, about $15. It's located on the back of the instrument cluster on the right side and is rectangular in shape.

410s 411s 510s and probably 521s all use basically the same Instrument Panel Voltage Regulator. 2 tabs plug into the mother board [unregulated voltage in, regulated voltage out. The mounting tab provides ground.] The differences are in the shape of the mounting tab which also grounds the case of the regulator. If what you get is not a spot-on replacement, bend the mounting tab to fit and for insurance add a short piece of 20 gauge or larger copper wire with crimpon or soldered end tabs under the mounting bolt to a good ground around the periphery of the mother board. If you can't bend to fit, use the grounding jumper to connect to the motherboard.

 

 

Quick check to verify VR problem, next time it starts to fluctuate or just doesn't respond give the instrument panel just above the 2 gauges a good swat with the palm of your hand. This will usually shock the mechanical VR into operation. Might take 2 swats.