Fuel sender units

[Farmer42]

The fuel sender unit is slowly dying on my 75 2/2 and I think i need to think about replacing it. I have had it out of the tank several times to clean contacts etc but it only shows a maximum of just over 1/2 full even when I fill it up to the neck.

There seems to be several on the market but the question I have is whether they are all the same or is the 2/2 different due to a different shape tank? Most seem to be aimed at the 2 seater and I don't want to spend money on the wrong part, especially if it has to be imported with all the costs of that, if it is not compatible with a 2/2.

Any advice would be appreciated.

 

[richiep]

I'm not sure tbh, but worth noting that eBay has, in the last few days, been flooded with fuel sender units for Zs made new in China, costing around 16 quid including post. At that price, it wouldn't be a huge disaster if it didn't fit.

Does it fit into the tank on facing the front of the car, like on a 2-seater? I know that late 280Zs had a sender mounted on top rather that the side, but that shouldn't be the case on your car. It might just be a case of the wire for the float needing some adjustment?

 

[Farmer42]

Thanks Richie

Yes, I have just been looking at the e-bay senders. Might give it a try and if it doesn't fit, I can always sell it on. Mine is a side fitting facing front but I'm pretty sure that the float arm was angled not straight. I suppose the best way is to get it out and have a look but will need to use some fuel before I do as the tank is nearly full and I have nowhere to store it. Will leave it until after Japfest now. At least it shows when I am running low on fuel so hopefully I won't run out on a motorway or something.

 

[richiep]

This might help from JDM car parts; I'm guessing yours might be the same as the earlier 280Z style pictured here, with the bend in it. Might just be a case of buying the cheap Chinese one and bending to shape:

Fuel Sender Unit Kit for Datsun 280Z 12/1974-7/1976 Type / 8/1976-1978 Type

Product Information: Part number: #11-J8201 / 11-J8202 Make/model: Datsun 280Z Descriptions: 11-J8201: $219 Fuel sender unit kit For Datsun 280Z 12/1974-7/1976 Replacement of #25060-N4202 Comes with O-ring Reproduction Comes with connector set Caution!: Please DO NOT use any tools on terminal...

jdm-car-parts.com

Bit of a difference between 16 quid and $219!!

 

[Geoff-R]

I watched the new sender units that have flooded ebay and got sent an offer the other day for £13, honestly at that price it's worth a punt.

 

[toopy]

I believe the sender is the same for both 260 and 2+2, just a matter of early or late model, but seeing as yours is 75 i would go early 280z as a start.

I seem to remember reading that 510 senders are the same, just the arm differs slightly and needs to be bent.

 

[Farmer42]

I watched the new sender units that have flooded ebay and got sent an offer the other day for £13, honestly at that price it's worth a punt.

Agree & punt taken. Should be arriving next week so will find out.

This might help from JDM car parts; I'm guessing yours might be the same as the earlier 280Z style pictured here, with the bend in it. Might just be a case of buying the cheap Chinese one and bending to shape:

Fuel Sender Unit Kit for Datsun 280Z 12/1974-7/1976 Type / 8/1976-1978 Type

Product Information: Part number: #11-J8201 / 11-J8202 Make/model: Datsun 280Z Descriptions: 11-J8201: $219 Fuel sender unit kit For Datsun 280Z 12/1974-7/1976 Replacement of #25060-N4202 Comes with O-ring Reproduction Comes with connector set Caution!: Please DO NOT use any tools on terminal...

jdm-car-parts.com

Bit of a difference between 16 quid and $219!!

Yes, quite a difference and this is why I raised the question. You could probably add another $150 for postage & duties on top of that. I might have some fettling to do when the e-bay unit turns up!!

 

[Farmer42]

So, my cheap Chinese unit arrived yesterday and as expected the shape of the float arm was different (see pic- old one on the right.)

Luckily there is a little screw that holds them on the body and the arms can be interchanged so I just swapped the old arm onto the new resistor body. It worked fine off the car but having fitted it, it only moves up to empty mark when I have about 1/4 tank. I think the arm will need bending a little to get the right measurements but hopefully should be ok.

If that lasts a couple of years, it was certainly worth the investment. Better than paying £200 for the wrong part!

 

[toopy]

Is there not an adjustment screw on the fuel gauge so you can dial in a new sender, rather than resorting to too much hit and miss bending of the arm, or have i dreamt that?!

 

[Farmer42]

Not heard of that one. Might be worth a check before I drain the tank again unless someone gives a definitive answer.

 

[toopy]

Is there not an adjustment screw on the fuel gauge so you can dial in a new sender, rather than resorting to too much hit and miss bending of the arm, or have i dreamt that?!

@Albrecht - is this something you mentioned Alan or am i getting confused with one of the other gauges?

 

[JK240]

I've only just seen this thread and realise you've got sorted, but if it helps I have a used 510 sender unit that I'd sell you for a tenner plus postage...?

Cheers,

JK

 

[Albrecht]

@Albrecht - is this something you mentioned Alan or am i getting confused with one of the other gauges?

I haven't got a fuel gauge to hand to demonstrate, but there should be an adjustment point on the back of the gauge (originally taped over at the Kanto Seiki factory when it was calibrated) which accepts a small flat bladed screwdriver and can be used to adjust the range of the gauge. Buggers to get to when the gauge is in the dash though.

 

[Farmer42]

Got the gauge out this morning and found 2 taped-over slots. They didn't seem to be moveable or adjustable though and the last thing I wanted to do was force it and break the gauge. I didn't see any other screws or other adjustable bits. I think I will stick to fiddling with the sender.

 

[Farmer42]

I think I have sorted the problem. The round body of the sender unit has a slot in it that locates into a corresponding tag on the tank to located the unit in the right position. The slot on new unit was slightly different so I installed it at the wrong angle causing the arm to stop moving upwards. Took the unit out and marked the bottom, reinstalled it and presto it registers the right fuel amount. Hopefully it wont leak through the o ring when I fill it up otherwise I'm back under the car and the petrol station will have a petrol puddle!

 

[Paul_S]

I think that's the key - the arm should have full travel in the tank and may need a tweak so it doesn't bind at any point.

Once you have full travel, then a tweak of an adjustment screw might or might not be necessary.

 

[Farmer42]

Just a word of warning for anyone wishing to get one of these Chinese sender units in eBay. The unit works great but the o ring provided with the unit is too small and will not seal the fuel in the tank as I found to my cost.

I thought I had it positioned correctly with the locking ring holding it all in place but when I filled up, the o ring folded in on itself and dropped into the tank resulting in loads of fuel leaking out. When I compared it to the old ring it was much smaller. Luckily it rested in the float arm so I could retrieve it and I had kept the old one so I could put it back on, not before I had got soaked in fuel.
So, the moral of the story is that if you are going to get one of these sender units, also invest in an OEM o ring and don't rely on the one supplied.