Will a 73 Charger fuel level sending unit work in a 74?

jogirob · Mar 8, 2019

Neither Orileys nor Autozone have a fuel level sending unit for a 74 charger but they have like 10 different options for a 73 and below. What gives???

To make things even more confusing, I go check out Classic Industries and they have sending units for a 74 B body but it's listed with with a 3/8" outlet and 1/4" return. My old sender has a 5/16" outlet and no return.

The '73 units I'm looking at through Autozone appear to have the exact curvatures I need in addition to having a 5/16" outlet and no return.

Hijinx · Mar 9, 2019

Try yearone, pretty sure i've seen them there and ebay. Does this one match what you have? https://www.yearone.com/Product/chrysler-b-body/bf657

YY1 · Mar 9, 2019

they should interchange.

the 73 tank has an external vapor manifold, the 74 tank's is internal in a hump on top of the tank.

I don't think that affects the sender

the outlet size is for your fuel requirement- 318 cars had the smaller, while big block and 340 cars had the larger IIRC

400sforever · Mar 9, 2019

Big block two barrel cars had 5/16 line also with no return. 440 4 barrel cars got a 3/8 with a return line. If I was you I'd restore the original gauge. You will be very disappointed with the new reproduction junk.

Hijinx · Mar 9, 2019

Does it really matter (unless you are a purist) to put in a 3/8 main 1/4 return? your lines are most likely all 5/16 so it should restrict it to 5/16's no matter what... most come in stainless steel as well.

jogirob · Mar 14, 2019

Hijinx said:
Try yearone, pretty sure i've seen them there and ebay. Does this one match what you have? https://www.yearone.com/Product/chrysler-b-body/bf657

That's exactly what the 73 fuel sender I ordered from Autozone looked like and arrived as. Ran into a couple fitment issues but bending the tubing myself fixed it. The sender output post that delivers the resistance readings appears to be too wide for the sensor lead so I had to cobble together an extension that plugs to the end of the car lead and used a nut on the sender's post to secure the other end. I didn't want to butcher the original wiring. Since it only delivers resistance readings I'm guessing it's safe to not have that makeshift connector booted and sealed, right?

Hijinx said:
Does it really matter (unless you are a purist) to put in a 3/8 main 1/4 return? your lines are most likely all 5/16 so it should restrict it to 5/16's no matter what... most come in stainless steel as well.

Yea I didn't realize how close of a fit it is between a 3/8 and a 5/16. A good hose clamp would probably seal em just the same and I guess I could've just capped off the return.

The new sender is in, I just need to add some fuel and start her up. Any particular procedures I need to follow? I figured I'd prime the system by pumping the gas pedal maybe 5 or 6 times and spray a little bit of starting fluid down the carb?

jogirob · Mar 14, 2019

Womp womp, should've known better but my little extension doohickey added a couple dozen ohms of resistance and now my fuel gauge readings are way down. Gonna have to tear into the original wiring it looks like. Oh well, better than having a non functioning fuel gauge.

400sforever · Mar 14, 2019

Don't do it! Your new gauge is junk. I'm sure your wiring is fine! Your gauge will not read full and your car will always seem to be out of gas! No one is making good working gauges for these cars yet

jogirob · Mar 14, 2019

400sforever said:
Don't do it! Your new gauge is junk. I'm sure your wiring is fine! Your gauge will not read full and your car will always seem to be out of gas! No one is making good working gauges for these cars yet

Oh my original gauge is just fine. I even hooked up the sending unit while outside the tank and moved the float to extremes to make sure I had a full sweep of the needle.

The problem is with the input lead near the gas tank that connects to the sending unit post. Turns out the boot was getting in the way. I filed the boot down a few mm and now the lead snaps on securely. I put about 7 gallons in and the needle barely makes it past the first tick near empty though. Once I get a brand new fuel neck filler grommet I'll fill the tank completely and see how far off my fuel gauge is.

400sforever · Mar 17, 2019

Sounds good. .my bet is that it will only read 3/4 full when filled. I ran into that 3 times now. Now I just restore my original senders and put them back in

Will a 73 Charger fuel level sending unit work in a 74?

jogirob

Well-Known Member

Hijinx

Well-Known Member

YY1

Well-Known Member

400sforever

Well-Known Member

Hijinx

Well-Known Member

jogirob

Well-Known Member

jogirob

Well-Known Member

400sforever

Well-Known Member

jogirob

Well-Known Member

400sforever

Well-Known Member

Similar threads