Any chance I can upgrade the fuel level sending unit in an 84 rx7 gsl? Don't think mine is usable and can't find one. How do I te

Everything I've seen has 3 wires plug mine has two plus this errant wire

 

That doesn't look too bad. These are not available new any longer.

Try sweeping the arm and measure the values.

...Fuel level sending unit- full=6 ohms / 1/2=31.5 ohms / empty=80 ohms.
...Fuel level gauge- full= 7.4 ohms / 1/2=31.5 ohms / empty= 75.9 ohms.

 

How do I hook up the meter what terminals? And I think mine is missing a terminal

 

According to the wiring diagram, my sending unit is supposed to have three prongs, y/b goes to fuse, y goes to gauge and black is ground. My unit is missing a terminal and my plug only has two leads.

I think a terminal is broke and missing

Only these two wires come out of the plug

 

Mine is definatly missing a terminal, this is a pic of a new one

New...mune is missing the third terminal

 

The Black is the ground and the Yellow goes to the fuel gauge. The Yellow/Blue (YL) goes to the fuel low dash light. Put the leads on the black (black lead) and the yellow (read lead) and use the 200 or range on the ohms part of the multimeter. Sweep it really slow. If the arm is stiff to move, use some wd-40 and spray it down inside. I've even blaster them in my sand blaster to get crud out. Yours from a look perceptive doesn't look that bad and that wire can be fixed.

 

Ok ill do that. The terminal is missing and the plug on the car only has two wires the third I don't know where that goes on the sending unit. Looks like someone tried to solder it to the lug on the top of the sending unit. Ill let you know what I figure out.

The lug on the bottom right, I think is supposed to have a terminal attached to it at the top

 

You can see in the factory one you posted that there is a piece of bent metal that goes from that soldered area to that slot that is missing it prong. You could bend a piece of metal up or just solder a wire onto that soldered area and tap into the unit side.

 

Right. I think ill try that thanks will let you know how it goes

 

also looking for a spark plug wire set either red or blue any links?

 

Ebay has supposedly new OEM Mazda ones. Just search 1984 rx7 fuel sending unit. They aren't cheap at $80-125 each, as well as being shipped out of Japan. But it could be an option if you need a new one.

As for spark plug wires and anything else you might need, look at rock auto. They normally have name brand stuff cheaper than everywhere else, just watch out for shipping it can be pricey.

 

I really like the NGK blue set NGK 8172. The best price I have found is on RockAuto for $15.25 + shipping (~$25) or Amazon (~25) I also like them because they are labeled 1 and 2.

 

Tested my sending unit....its shot no resistance..my meter does not move at all. Time to find a good used one or switch ouy the gauage and use an aftermarket one

 

You can still use the factory gauge, just make sure the new aftermarket float sweep ohms are close to what I posted. You could also try sand blasting the sweeper inside that top square box.

 

I can't get it open without breaking it all apart

 

Maybe soak it in vinegar or rust dissolver.

 

been looking and cannot find any sending unit with the ohms required, everything im finding is 33 ohms full and 240 empty

 

You might be in luck. I am getting ready to post a fuel sending unit that came out of my '82 race car. It looks pretty much like yours though so the tank may not have been the original to the car. Anyway, I am posting it for free. Just pay shipping. Post should show up in about 15 minutes. PM me if you are interested.

Carl

 

I bought a set for my repu from rockauto... ebay, rockauto, build your own kit.. lots of choices

 

Bought an 84 GSL-SE at salvage. Got it to crank but wouldn't run.

Tank was totally traahed inside. Fuel level sensor too. Took me a month and a half to find folks who said they had one, then none would sell.

Finally found a great guy to show some compassion. Even then, it didn't work, but I was able to salvage enough to bring mine back to life.

Good luck.


Inside my tank. The 'in-tank' syphon tube filter screen waa also trash.



Mine, out of my 84 GSL-SE, on the left. Its didn't register anything on the ohm meter and the 'low full' sensor was totally shot.






The one I found. You can see the coiled resistance wire was damaged. But I was able to salvage the 'low fuel' sensor.

 

you can get new ones.. they are a different number than stock.. miata part number I think..

 

I went to the dealer and asked about other models that might work.

They didn't come up with anything.

if you recall that Miata part number please do share.

 

yeah Ive just been searching my emails... I replaced it in my gslse too...|

Ill keep looking but it was like 4 yrs ago.. maybe its in my thread Ill check

 

Did you find a sending unit? I have one I fixed by soaking in injector cleaner (Techron) - it ohms good. I had already installed a $200 NOS one I got from Puerto Rico - allegedly the last new one on the planet. DM your address and you can have it. If you like it you can PayPal me $50

 

Yep, found a guy who had one.

I used his parts to rebuild mine.

Thanks for asking.👊🏾