fuel sending unit (which way is up?)

[Jeff Berk]

Looking at this picture:

https://zcardepot.com/collections/fuel-sending-units/products/fuel-tank-sending-unit-oem-240z-260z-70-74

Is this sending unit right side up?

I took mine out when I removed the tank for cleaning/coating and cannot remember which way the unit goes. 

I need to learn to take more pictures when I take things apart. 

Jeff

[siteunseen]

Right side up is when the arm raises up. When it's all the way down you're on empty.

If you still have the old one lay them side by side. You may need to bend the new one to match. I didn't and now a quarter tank on the gauge is empty inside the tank.

[siteunseen]

Also the float runs horizontal like the photo. Kinda tricky getting it in but not too bad. Good luck!

[AZ-240z]

I am going from memory, but I seem to remember that the sending unit is keyed so it will only

go in one way.

also, no need to bend the float arm.  If you look closely at the float arm pivot point, you will find a

set screw which allows you to adjust the travel of the float.

hope this helps.

 

Dan

[Jeff Berk]

I guess I wasn't clear. I'm not replacing the unit but I'm unsure which way to put the old one back in after dropping the fuel tank to coat it inside.

I'll look for that set screw assuming that limits travel up.

Worse comes to worse, if I put it in upside down, I should be able to flip it without having to remove the tank a second time.

[zKars]

It is keyed. Little slot on the edge of the sender plate and matching nub on the tank where it fits into the key

[ollie]

On 3/26/2019 at 3:22 PM, siteunseen said:

Right side up is when the arm raises up. When it's all the way down you're on empty.

If you still have the old one lay them side by side. You may need to bend the new one to match. I didn't and now a quarter tank on the gauge is empty inside the tank.

I am in the exact same boat, sort of anyway...I find that mine will show almost full right upon filling the tank but has about 1/4 tank upon empty which doesn't make a ton of sense, to me anyway.  Suggestions?  

[siteunseen]

Your's is the opposite than mine, damn it! 

You have a "reserve" like a motorcycle does.  I only could wish for that scenario.  haven't been stranded so far but it is nerve racking when I'm on the interstate.  I pretty much top mine off after each drive.  I didn't know about the set screw they talk about above.  One day when I'm really bored and can't sleep I may pull mine and see if I can get it right.

Is there any chance your gauge glass is hitting the needle?  I say this because when I bought mine the sending unit was rusted frozen and the guy I bought it from had "tapped" the heck out of the gauge causing the glass to fall inwards and hinder the needle sweep.

Best of luck!  Cliff

[ollie]

55 minutes ago, siteunseen said:

Your's is the opposite than mine, damn it! 

You have a "reserve" like a motorcycle does.  I only could wish for that scenario.  haven't been stranded so far but it is nerve racking when I'm on the interstate.  I pretty much top mine off after each drive.  I didn't know about the set screw they talk about above.  One day when I'm really bored and can't sleep I may pull mine and see if I can get it right.

Is there any chance your gauge glass is hitting the needle?  I say this because when I bought mine the sending unit was rusted frozen and the guy I bought it from had "tapped" the heck out of the gauge causing the glass to fall inwards and hinder the needle sweep.

Best of luck!  Cliff

We're in the same boat...mine definitely sweeps OK, it just sweeps the span from full to empty out of scale, if that makes any sense.  Plus the car has been running rich so it chugs the fuel like no tomorrow.  That was dealt with this weekend.  Anyway I am going to pull it out perhaps this weekend and run the car out of gas at the house.  Then pull the sender and see what's up.  It is all in the "as full restored" state and was a brand new sender when the tank was boiled, etc, during the restoration.  Unfortunately I simply threw the original sending unit away long ago...cheers.

[ramsesosirus]

On 3/26/2019 at 5:22 PM, siteunseen said:

Right side up is when the arm raises up. When it's all the way down you're on empty.

If you still have the old one lay them side by side. You may need to bend the new one to match. I didn't and now a quarter tank on the gauge is empty inside the tank.

So will that one you linked to work for a 76 280z?  I can only fill my tank about 1/2 or 3/4 full, when the level gets to the sending unit, it drips...

I've already tried to epoxy the connections, as well as put on a new o ring and the locking cap.

I can just get that one and bend the rod?  I'd love to be able to fill up all the way!

[siteunseen]

I'm not sure what sending units work on which years.  Seems like the side mount would be the same but they say up until 1974.  i thought '75 and '76 had the side mount too?  I know my '77 drops in from the top, under the hatch deck.

here's the part numbers for Nissan sender and o-ring, $50 is what I paid a few years ago from my local dealership.  part number is on the box in one of the pics, o-ring number is written in the post.

You've been dealing with this for awhile I see.  Hope you get it fixed!  Cliff

 

[ramsesosirus]

32 minutes ago, siteunseen said:

I'm not sure what sending units work on which years.  Seems like the side mount would be the same but they say up until 1974.  i thought '75 and '76 had the side mount too?  I know my '77 drops in from the top, under the hatch deck.

here's the part numbers for Nissan sender and o-ring, $50 is what I paid a few years ago from my local dealership.  part number is on the box in one of the pics, o-ring number is written in the post.

You've been dealing with this for awhile I see.  Hope you get it fixed!  Cliff

 

Cool thanks.  Yeah, it's pretty much the only real issue I have with the car right now (of course there are small things always on a 40+ year old car).

After I couldn't get the leak to stop, my solution just became not filling the tank completely full... and THIS is why:

https://zcarsource.com/rebuilt-280z-gas-tank-sending-unit-for-the-1975-76-datsun-280z

The 75-76 one is $250 for a rebuilt one, and you send them your old one.  That's why I was looking at an alternative.

And yes, 76 does go in from the side of the tank.  I wonder if it would be possible to "block" the hole in the tank, and remove the sender completely?  My last DD's fuel gauge didn't work, so I went with the tripmeter reset method... until I didn't want to completely fill the tank.  I ran out of gas a few times haha.