Fuel Sender calibration using Meter Match

[3175375]

Not impressed with this Ryobi scope. Not very bright and the focus and definition isn’t that good. Maybe it will be better in a smaller area or somewhere with a little more light.
View attachment 372724 View attachment 372725

Does the meter calibrator device have a dampening function? That is, is there a way to average, or smooth the sampled data from the rheostat?

I worked on a liquid cooling system controller and the software puke I worked with did something like that after I convinced him that the mix valve we were using couldn’t physically jump all around the place. He implemented a 10 second moving average function on reading the mix valve position and our noise problems vanished...

 

[HWYCRZR]

Yes it does have a dampening and averaging feature. The meter match is doing its job but I shouldn’t be getting an 1/8 to 1/4 tank difference between idling in the garage and driving steady on the road. I pulled the tank down anyway to put the other known sender that is steady. I took a picture inside my tank. It seems my clocking is off. It is sitting at a weird angle. Tank is flat.

 

[HWYCRZR]

Better picture

 

[Polara_500]

Yes it does have a dampening and averaging feature. The meter match is doing its job but I shouldn’t be getting an 1/8 to 1/4 tank difference between idling in the garage and driving steady on the road. I pulled the tank down anyway to put the other known sender that is steady. I took a picture inside my tank. It seems my clocking is off. It is sitting at a weird angle. Tank is flat.
View attachment 372740

And it doesn't appear the float is in the gas.

 

[HWYCRZR]

My original must have gotten bent sometime. The clocking tabs are ok, but totally different from my re pro. To be fair my original sat in a parts box with a bunch of other stuff for 13 years. Then again my old tank had a few big rock dents. Maybe it was pounded up.
Here is how my repro sets. Same tank angle.

 

[HWYCRZR]

And it doesn't appear the float is in the gas.

Either was the pick up. Now at least I cannot see the pickup.

 

[Big_John]

Thinking about it, your original could have gotten twisted when the hose was removed. If you think about it, what do you do when taking off a stuck hose? Give it a twist back and forth and a couple yanks. It may not be that secure in the mounting plate.

 

[Polara_500]

They're supposed to have a notch in the tank with a matching tang on the sender to ensure alignment.

 

[HWYCRZR]

The indexing tabs weren’t bent and based on the alignment it was clocked right. But compared to my replacement it is tweaked or twisted inside the tank.
Oh well. Am going with the replacement.
Held all the way down in the tank it is 77 ohms 74 is supposed to read empty. Held to the top, it reads 8 ohms. 10 is supposed to be full. So now it is going to depend on the angle the tank sits in the car. Are my springs a little saggy so I cannot fill it all the way up? We will see. By the way I did tip it all the way up to make sure the sending unit gasket wasn’t leaking. I am learning but slowly after a couple of leaks.
I am not convinced it is the locking rings on the new tanks leaking. It is all about gasket placement and keeping the locking ring centered. Both of my leaks were from trying to install the sending unit under the car. I couldn’t see that the gas had slipped a little and locking ring offset to one side.
Going back in.

 

[HWYCRZR]

Done. When I put I back on. I set the low end to Empty. Then I loaded up my gas can and tried to run it out of fuel. I drove 22 miles on my normal loop and still didn’t run out. I had to be close. I put 2-1/2 gallons back in and adjusted the low end to just above the empty line. Then went and filled up and set the top end so the needle was a little above the full line.
In all I put in 22 gallons, so I am getting the volume. At least I know I have 22 usable gallons.
Meter match set. No more bounces or fluctuations. I think I will be happy now.
Moral of the story is stat with a sending unit that you know before you hook up fancy technology to it.

 

[cbarge]

Moral of the story is stat with a sending unit that you know before you hook up fancy technology to it.

So,would you recommend the MeterMatch then?

 

[HWYCRZR]

So,would you recommend the MeterMatch then?

Now that I have a known good sending unit it seem to be working great. Give me a couple weeks when I get down to around 1/2 tank and re- fuel to see the mid range accuracy.
So far it takes care of my OCD that cannot stand when the gauge only reads 3/4 wit a full tank.
I like it quite well, but still need to validate.

 

[Big_John]

So,would you recommend the MeterMatch then?

Now that I have a known good sending unit it seem to be working great. Give me a couple weeks when I get down to around 1/2 tank and re- fuel to see the mid range accuracy.
So far it takes care of my OCD that cannot stand when the gauge only reads 3/4 wit a full tank.
I like it quite well, but still need to validate.

I really like mine. Nicely built and once you figure it out, you can make the gas gauge (or other gauges) very accurate.

 

[cbarge]

Now that I have a known good sending unit it seem to be working great. Give me a couple weeks when I get down to around 1/2 tank and re- fuel to see the mid range accuracy.
So far it takes care of my OCD that cannot stand when the gauge only reads 3/4 wit a full tank.
I like it quite well, but still need to validate.

I have friends with repop senders and they also complain about inaccuracies.
So i am watching with interest and will be ordering one for myself.
Others may just do the same,,who knows,eh>>
Cheers

 

[HWYCRZR]

Thinking about it, your original could have gotten twisted when the hose was removed. If you think about it, what do you do when taking off a stuck hose? Give it a twist back and forth and a couple yanks. It may not be that secure in the mounting plate.

I think you were right. I was seeing if I could straighten it and the whole tube turned through the sending unit. It would have been a matter of time before it started seeping or leaking.

 

[HWYCRZR]

Update/ no update.
When I filled up after calibrating my meter match I took a picture of the mileage. Well my phone was getting short on storage and I deleted the picture. I did find one that was close to the time I filled but maybe had 20-50 miles on it since then. Anyway The gauge was getting close to 5/8 and I had a little over 120 miles from the mileage I found so I decided to fill it up. I only got 9.5 gallons in it to top it off so my gauge must be close to accurate.
I did write the mileage down this time.
8793.7 miles.
2,308 miles since the restoration and getting on back on the road last May.

 

[Timmayy]

Isn't there someone that can rebuild the factory sending unit?
Also, I like Big Johns idea of soldering a tab for a separate ground wire. I myself drilled a small hole on the tab of the lock ring and soldered ground wire there.