Hi EconoRat,
I've worked on '61-'63 Falcons for a while and have run across this problem a few times with my
own and friends' cars. Now I got an Econoline Pickup and the Gas Gauge is broke too. I'm gonna
fix it soon. The Falcon and Econo are pretty similar. Here is what I do:
-You will need a voltmeter with a needle readout, not a digital one.
-A test light.
-2 batteries, I use AA, taped in series (end-to-end.)
-wire with "alligator" clips on the ends (you can use tape but not as easy.)
TEST SOURCE GOING INTO THE CVR
The Constant Voltage Reg (NOT the voltage regulator for the generator!
) is right behind the
speedo. It's a little tin box, has two leads, Black/Green wires. Test the incoming wire for voltage
first. Incoming is a SINGLE B/G wire, outgoing is a single B/G wire that splits into a double B/G wire for
both Temp and Fuel.
Connect meter to the incoming post and ground the other lead to dash metal. Turn IGN key to "on."
You should get about 11-13 volts, steady.
TEST VOLTAGE LEAVING THE CVR
Connect meter to outgoing post on the CVR and ground the meter again. Turn the key "on."
You should get a voltmeter that bounces up and down between 0 and 10 volts, it looks like a
heartbeat. Average voltage is 5 volts which is what both gauges need to operate. (This is why
you must use a Meter with a needle, I found digital meters "skim" over that important oscillation
and will read the "highs" which is misleading.
If a Meter is not available, you can rig a 12v light from the outgoing post on the CVR to GND, and
the bulb should dim and brighten, like a heartbeat.
TEST THE FUEL GAUGE
Connect the "AA" batteries in series between both posts of the Fuel Gauge. The gauge should go to
almost full in about 30 seconds or so. This is also true for the Temp Gauge.
TEST THE WIRE GOING TO THE GAS TANK
Assuming the Fuel Gauge is connected and the Gauge Cluster is re-installed in the Dash:
Pull the wire off the Fuel Sender Unit and ground this wire to nearby clean metal. Momentarily
turn IGN to "on." Fuel Gauge will quickly go to Full. (Shut down quickly after verifying gauge
function. The gauge is supposed to handle 5 volts not 12+.) Note: NEVER connect 12V to the
Sender as some sort of test, it will fry.
TEST THE GROUNDS
In my experience this is what the problems usually end up being at least in part.
Check 4 contacts.
1. Battery POS to Starter Solenoid (if your Econo Starts/Runs then it is a foregone conclusion.)
2. Battery NEG to Engine Block, usually at the front of the block. (CLEAN both ends up real good!)
3. Engine Block to Body (This is usually at the rear of the block, NOT directly connected to #2 above,
to prevent "noise.") This one gets neglected! Some cars will run without one, ha, but not at their best.
4. Body to Fuel Sender, from what I've seen on the Econolines, this connection can get pretty messed
up. Typical route is the Fuel Sender, to the Locking Ring, to the Tank itself, to the Body. (LOTS of
places for rust and crud to reduce the continuity!)
I'd suspect #3 and 4 as the final culprits. Take your time cleaning and making BARE metal contact.
I use dielectric grease (looks like Vaseline) on the contact points to make them stay good for longer.
I might even make a wire connecting the sender directly to the body.
Most guys go right for the Regulator or the Sender. I've found that those parts seem to last pretty
well over time, but still need to be checked.
Hope this Helps,
George
BTW, please follow up on what you find, to increase this threads' worthiness...
by Guest Tue May 25, 2010 7:16 pm
