• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR2/3/3A fuel gauge / sender TR3A

Share this page

Randall:

Gotcha!
 
This is almost the exact information I've been seeking. I am trying to piece together a TR3 and have purchased (from ebay) some guages. I think I have a TR4 fuel guage with curved glass. I also have a tank sending unit that came in a TR3 tank and two that came from NOS (new). I have 2 other fuel guages (with flat glass) probably from a TR4. All these guages (don't) work the same -pretty much the opposite but also without full range. The new sending units were supposed to be for a TR4, but with an ohm meter, they read the same as the TR3 (roughly 90ohms=full 0=empty.

Assuming I have TR4 gauges, what should the sending unit measure when empty/full?
Any help would be... very helpful.

Jerry
 
I don't have the numbers handy, but if it reads zero empty, it can't be from a TR4. The TR4 sender reads zero full.

Flat glass is definitely TR4 or later; but early TR4 had curved glass gauges that look virtually identical (from the front) to TR3 gauges. However, if you look at the back of the gauge, the TR3 style gauge will have two slots & nuts on the outside for the adjustment (as shown below), while the TR4 gauge has two round windows (with slots possibly visible inside) and no nuts.
 
Thanks. It looks like you understand my frustration.

That's right, it has a curved glass on the front but the back has two holes with slots. I have pictures, but don't know how to upload them.

So what sending unit do I put in the TR3 tank?

Jerry
 
Probably the best thing would be to try to find a TR4 owner that mistakenly bought a TR3 fuel gauge /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

If you do keep the TR4 gauge, you'll want a voltage stabilizer to go with it; and a sender that reads zero ohms when full.
 
Thanks. I think I'll order the TR4 sender from MOSS. My TR6 sending unit seems different from either the TR3 or what the TR4 should be. I have a TR4 voltage stabilizer and I've tried adding that to the circuit. I've even tried taking apart the sending unit and reversing the rheostat so ground is at the other end -but the full range is not correct.

I feel better knowing that there are differences between TR4 and TR3 sending units. -even though the supplier claims to have sent me 2 TR4 units. I've wasted a lot of money by trying to save money on ebay.
 
Back
Top