The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1960 - 1966 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 04-20-2022, 10:20 AM   #1
65C10ED
Registered User
 
65C10ED's Avatar
 
Join Date: Oct 2020
Location: Hampshire, IL
Posts: 11
90ohm <-> 30ohm

I installed a '69 Camaro tank under my '65 and find the sending unit is not working correctly with my stock '65 fuel gauge. From what I have discovered, the '69 sending unit is 90ohm, while the '65 fuel gauge is 30ohm, thus the incorrect reading. My question is, if I purchase a new fuel tank sending unit for a stock '65 in-the-cab tank, would it be possible to swap the 30ohm resistor of the '65 sender with the 90ohm resister of the '69 sender in order to make the '69 sender work correctly with the stock '65 gauge? Has anyone done this?
65C10ED is offline   Reply With Quote
Old 04-20-2022, 12:24 PM   #2
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: 90ohm <-> 30ohm

A couple of suggestions in this one thread - http://67-72chevytrucks.com/vboard/s...d.php?t=600116
If the tank is 6 inches deep you can use this - https://www.summitracing.com/parts/tnk-t-gme-06
Or 5 inches deep - https://www.summitracing.com/parts/tnk-t-gme-05

Last edited by The Rocknrod; 04-20-2022 at 12:32 PM.
The Rocknrod is offline   Reply With Quote
Old 05-12-2022, 03:23 PM   #3
65C10ED
Registered User
 
65C10ED's Avatar
 
Join Date: Oct 2020
Location: Hampshire, IL
Posts: 11
Re: 90ohm <-> 30ohm

Update to my queston: Along with my 69 Camaro sender that came with the new gas tank, I also had a sending unit from the 59-60 Impala tank I had attempted to use prior to the Camaro tank. The sending unit from the Impala had basically the identical parts the Camaro sending unit had except for the shape of the pickup tube and the resistor/rheostat was 30 ohm. So, I figured I could take the resistor/rheostat out of the Impala sender and install it in the Camaro unit. It worked! I changed my 90 ohm Camaro sender from 90 ohm to 30 ohm and it was pretty easy. See the attached photo.... 1. The "can" that holds the resistor is held together with just 3 metal tabs. I just folded them open and the can opened up. There's one loose spring inside that goes on the end of the float shaft. 2. Inside the yellow container is the resistor/rheostat that is an arched strip of metal with very fine wiring wrapped around it. It's the same kind of thing that is inside slot car controllers and it's attached to the container by only one brass rivet that holds the resistor/rheostat as well as attaches the power wire. I carefully drilled out the rivet from the outside....removed just enough to remove the rivet. 3. Then I was able to remove the rivet and the resistor/rheostat. To reassemble the Camaro sender I installed the 30 ohm Impala resistor/rheostat in place of the Camaro one and then hammered the old rivet back in where it was originally. Because when I drilled it out the rivet was shorter, I ground down the block the rivet goes through just enough to give me more rivet on the end to hammer down. Before hammering down the rivet, the power wire has to be included inside the rivet. Once I got the rivet as tight as it was originally I was able to reassemble the can and fold back the tabs. I noticed that the rivet needs to partially cover some of the fine wiring around the resistor/rheostat to be sure there is a connection and I had to move some of the fine wiring to put it in correct position. 4. But care must be taken with the fine wires.... they seem pretty fragile. So after I reassembled the sender, I connected it up to my 65 gauge and it worked! As I raised and lowered the float arm, the gauge responded.
Attached Images
 
65C10ED is offline   Reply With Quote
Old 05-14-2022, 02:55 AM   #4
SOON2BLAZE
Account Suspended
 
SOON2BLAZE's Avatar
 
Join Date: Aug 2005
Location: Southern UT
Posts: 906
Re: 90ohm <-> 30ohm

Good write up. Using the same 69 tank on my 66. I was going to get a NOS GM gas gauge from a 70-80's from ebay and pilfer the 90 ohm resistor off the back of the gauge and added it to the 66 gas gauge.
Dophin also makes a ohm converter
https://www.ebay.com/itm/26550897351...cAAOSwVbph7t4D
SOON2BLAZE is offline   Reply With Quote
Old 05-14-2022, 09:43 AM   #5
The Rocknrod
Moderator

 
The Rocknrod's Avatar
 
Join Date: Aug 2011
Location: China Spring, TX
Posts: 7,280
Re: 90ohm <-> 30ohm

Pretty cool.
The Rocknrod is offline   Reply With Quote
Reply

Bookmarks

Tags
30ohm, 90ohm, fueltank, gauge, sendingunit


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 06:35 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com