521 guage repair

[datsunfish]

Coming back from Canby my fuel guage went out.It would sometimes drop off then show back up.It is usually thought that the voltage regulator for gas and temp on the back of the guage cluster is the problem.True but not necessarily a bad regulator.I took mine out and un wrapped the case to find a very tiny clip that makes a ground contact to the housing body.This part was not making continuity.Take it out,sand it clean,put back together and voila!Fixed.I would think most of the ones thought to be bad are just dirty so if your guages on a 520/521 fluctuate or do nothing take the thing apart and check it out before you replace it.

[Pacific coast Datsun]

Good to know it's an easy fix. Any idea if a 620 fuel gauge could be fixed using the same method.Mine fluctuates alot & i never really know how muach gas i have.

[datsunfish]

I cant remember off hand if it has the same regulator but it is the same principle.Check at the tank for ground signal and continuity to the dash wiring.+ on one side and full - to the other should make it read full but if it has a regulator you probably shouldnt apply full 12v to the guage to test so I will look at my 620.

[denveratsun]

:mad:I did the same thing after getting tired of hitting the @#$@ thing all the time:D

Good to know I'm not alone.

[crabbyone]

Mr. Datsunfish sir;

I don't suppose you took any pictures of the "exploratory surgery performed", did you? It would be very nice of you, and very well appreciated by at least myself, if you would do it all over again....with pictures for posterity. I can put you, as a Datsun truck owner, on the waiting (ahem) list for a genuine Japanese Trucking Association window sticker....if, and when they ever get printed up.

 

Regards,

Crabbyone

[MikeRL411]

Take it out,sand it clean,put back together and voila!Fixed.I would think most of the ones thought to be bad are just dirty so if your guages on a 520/521 fluctuate or do nothing take the thing apart and check it out before you replace it.

 

Good fix to a common early Datsun problem. A drop of flux and some careful soldering, assuming the connection is not to the cover, would seem to be a permanent fix. A parallel flying wire to the base in case of lid connection might be a good idea too.