RCR fuel level sending unit specs

N

NickV

Hey everyone...
Spent some time this evening trying to nail down the exact fuel level sending unit that is supplied with the RCR kits. Recent build threads show what I believe to be a capacitive style "rod" sending unit that can be trimmed to length. Can anyone please confirm? If so, is there a part # on it? I'd like to get ahold of the spec sheet or some documentation stating what the output curve is. At the very least, an empty and full reading.

If no one knows I can always reach out to RCR but figured I'd try this first.

Thanks in advance!

1650944452441.png
 
ckouba

Chris Kouba

Supporter
I have the bladder inserts but they take something similar. I believe they are resistor type units (at least mine are). What you need to know is the resistance your gauges are expecting to see and work from there. It was a while ago but I believe the two common ones were 33-240 Ohms (yeah, makes very little sense) and 0-180 Ohms.

If you know the Ohm range and then measure the height of the tank you have to work with, find one which is slightly shorter (won't bottom out inside the tank and not seal at the opening). Make sure it has the correct bolt pattern and you should be good to go.

 
manta22

Neil

Supporter
"...33-240 Ohms (yeah, makes very little sense)..."

It does actually does make sense; the range is arbitrary as far as I know but the offset value of 33 ohms is to distinguish the low end reading from a short circuit. In a 0 to 180 ohm system, you don't know if a zero ohm reading is because the tank sensor is at one end of its scale (full or empty) or if the wiring is shorted to ground. The industrial current loop 4 to 20mA system is similar. A 4mA reading shows that the loop isn't an open circuit.
 
N

NickV

ckouba said:
I have the bladder inserts but they take something similar. I believe they are resistor type units (at least mine are). What you need to know is the resistance your gauges are expecting to see and work from there. It was a while ago but I believe the two common ones were 33-240 Ohms (yeah, makes very little sense) and 0-180 Ohms.

If you know the Ohm range and then measure the height of the tank you have to work with, find one which is slightly shorter (won't bottom out inside the tank and not seal at the opening). Make sure it has the correct bolt pattern and you should be good to go.

Click to expand...

Hey Chris thanks for getting back to me and for the info. I'm still hoping someone sees this with a RCR kit that can share a part # or the ohm readings for the RCR supplied specific sensor. I am going to use a standalone ECU so I need to program it to properly interpret the resistance output.
 
GTSean

Sean S.

Supporter
Nick Vandervoort said:
Hey everyone...
Spent some time this evening trying to nail down the exact fuel level sending unit that is supplied with the RCR kits. Recent build threads show what I believe to be a capacitive style "rod" sending unit that can be trimmed to length. Can anyone please confirm? If so, is there a part # on it? I'd like to get ahold of the spec sheet or some documentation stating what the output curve is. At the very least, an empty and full reading.

If no one knows I can always reach out to RCR but figured I'd try this first.

Thanks in advance!

View attachment 122305
Click to expand...
Hi Nick,

That picture looks familiar for some reason...lol

My RCR kit came with the cut to length rod style sender. I am currently out of town, but I can get the part number when I get back home at the end of the week for you. There was an instruction sheet that came with them too, I don't remember if it had specs on it or not. I will find them and send it your way as well.

I do remember reading on the instructions for the gauge that it has to be calibrated to the sender.

Regards,

Sean
 
GTSean

Sean S.

Supporter
Mstarkey3 said:
Hi Nick,

That picture looks familiar for some reason...lol

My RCR kit came with the cut to length rod style sender. I am currently out of town, but I can get the part number when I get back home at the end of the week for you. There was an instruction sheet that came with them too, I don't remember if it had specs on it or not. I will find them and send it your way as well.

I do remember reading on the instructions for the gauge that it has to be calibrated to the sender.

Regards,

Sean
Click to expand...


Not sure if this helps, but zoomed in picture of sender attached. A few numbers are legible, not sure if they are part numbers or not.

Sean
 

Attachments

  • IMG_6735.PNG
    IMG_6735.PNG
    1.2 MB · Views: 134
N

NickV

Mstarkey3 said:
Not sure if this helps, but zoomed in picture of sender attached. A few numbers are legible, not sure if they are part numbers or not.

Sean
Click to expand...

Hey Sean,

LOL I wondered if you would come across this.

Thank you that would be awesome! I will try and dig up something with the zoomed in picture in the meantime.
 
N

NickV

bryanf said:
This is the sender which is the correct length without needing to be cut.

View attachment 122313

Speedhut told me not to cut the longer one that it would not read reliably.
Click to expand...

Hey Bryan, awesome!!! That answers that! Should I reach out to Fran to make sure I get the correct sensors? Sounds like you were sent the wrong one? Where you able to exchange?
Thanks!!!
 
bryanf

bryanf

Nick Vandervoort said:
Hey Bryan, awesome!!! That answers that! Should I reach out to Fran to make sure I get the correct sensors? Sounds like you were sent the wrong one? Where you able to exchange?
Thanks!!!
Click to expand...
Speedhut swapped my two senders out for no charge other than shipping, but I am not sure if they still keep them in stock. Seems RCR routinely sends the parts that are too long to fit the tanks. Several people have mentioned this issue.
 
N

NickV

bryanf said:
Speedhut swapped my two senders out for no charge other than shipping, but I am not sure if they still keep them in stock. Seems RCR routinely sends the parts that are too long to fit the tanks. Several people have mentioned this issue.
Click to expand...

I couldn't come up with a spec sheet but that's okay. I can manually plot an output curve once I get the parts in.

I think I am getting confused in all the different terms being used to describe fuel level sensors.
I honestly thought the RCR kits come with a float-less fuel level sensor like this:
1651025536160.png


But it looks like maybe instead they are the float style like this:

1651025220933.png


Can anyone please confirm?

Regardless...
I couldn't get the RCR version Sean posted to show up on the Speedhut website or anywhere for that matter. I guess RCR special orders them, which would also explain the special sticker.

Searching that part number you shared pulled up the float style pictured below. I am pretty sure this clears up my confusion as to what exactly type of sender is supplied these days. Their website states that this style is adjustable and can fit any tank 5"-24" deep. This leads me to be surprised to hear they don't recommend cutting the RCR supplied one... where they recommending not cutting the pickup tube or the float arm?
1651025388163.png


Sorry I think I am misunderstanding the situation here...
 
N

NickV

bryanf said:
Here are the original (right) and replacement (left) senders. None of them were the float type.
Click to expand...

ahhhhh that makes much more sense. Now I am back on track. I will reach out to RCR and see if the shorter ones will be supplied. Curious that the part number pulled up a different gauge all together...

Thanks for the tips.
 
B

Brian Kissel

Staff member
Admin
Lifetime Supporter
Here’s a previous post about the senders.

Centroid Fuel Sender

Most of us probably have the original Centroid fuel level sender in the tank. I believe the unit we have has continuous output of 2.33V empty and 0.54V full. My fuel gauge is based on ohms (240 empty and 33 full). 240/33 is the factory default setting from Speedhut for the fuel gauge (it is...
www.gt40s.com

Regards Brian
 
GTSean

Sean S.

Supporter
bryanf said:
Here are the original (right) and replacement (left) senders. None of them were the float type. You can see part of the instructions in the picture detailing how to cut them.

Sean

View attachment 122320
Click to expand...


These are the ones I received, before cutting and after cutting. I needed to cut them almost in half. Odd they are so much longer than the ones you were supplied.

I Didnt talk to Centroid about them, just had instructions explaining how to cut them.
IMG_6427.jpg
 
N

NickV

This is definitely making sense now. I hadn't connected the dots that Centroid actually manufactures all of these and not speed hut.
I appreciate everyone's help clearing this up...

With this new info I was able to find the same instruction sheet online as pictured partially above which is extremely helpful.
Definitely some more reading to do once I confirm RCR kits still supply Centroid products.
 
S

Kyle

Supporter
 
You must log in or register to reply here.

Similar threads

T
***SOLD*** SLC for Sale (sold)***SOLD***
2
Replies
22
Views
10K
Brian Kissel
B
G
Fuel Level Sending Unit
Replies
3
Views
1K
Howard Jones
Howard Jones
A
Notes on Fuel Level Sender Calibration
2
Replies
20
Views
8K
Mark IV
Mark IV
D
Pilot jokes
Replies
3
Views
1K
blueovalz
blueovalz
gt40fran
Superlite coupe starting under $10,000
2
Replies
27
Views
11K
gt40fran
gt40fran
Back
Top