B. Figueroa

Still in the process of working on water temp gauge problem, but also noticed on my old printed circuit board , fuel gauge circuit is burned. I replaced the circuit board and fuel gauge, but I ran out of fuel at a 1/4 tank reading. Could the burned circuit board also have fried my sending unit? If so how do I gain access to the fuel sending unit??

0Willcox Corvette

B.. did you read my other post.. ???

If you installed the resistor with the new fuel gauge this might explain the issue. Remove the resistor and remove the other ones too on all new gauges installed. If you don't none of them will work properly. Only use the porcelain resistor with original style gauges.

Now.. If your fuel gauge works from empty to 1/4 of a tank then your resistor is blown.. but you said it ran out at 1/4 which says you must have that resistor installed.

IMHO,

Willcox.

B. Figueroa

I checked the old gauges and they have their resistors still mounted on the back, but the new gauges look like they came with resistors on the back. Are you saying I need to remove the resistors that came mounted on the back of the new gauge??? I did have an extra nut on the 4th terminal of the temperature studs. removing that nut allowed the temp gauge to start working. The gauge climbed from 0 to 160 degrees then when the thermostat opened it dropped back to 150 degrees. Makes me think I need to remove the resistor that came with the gauge. I appreciate your help and patience w my problem.

B. Figueroa

Willcox can you tell me were I can get Delco temp sending unit. The one Im using is from Auto Zone for a 350 Chevy Block.

B. Figueroa

Willcox..still wondering if the resistors you suggested I remove are the ones from the old gauges or the resistors on the new gauges. I didn't use the resistors from the old gauges but it looks like the new gauges come with resistors attached.

0Willcox Corvette

You can't.. None of the senders will read correctly.. but I have a solution that will be available within the next 60 days.

0Willcox Corvette

New reproduction gauges have the resistor built into them... so you don't use the original ones with the gauge. If you do, the gauge will not read correctly.

If you go to my site, I have info on how to diagnosis gauge issues for temp, fuel and oil pressure. It's there.. video's.. and pictures...

Look under tech pictures and tech video's.

I'll post more tomorrow, it's a bit late and my wife is giving me the evil eye..

Willcox

B. Figueroa

Happy wife ...Happy life

0Willcox Corvette

Okay.. I had to go look at your other post to figure out what year the car was. 77 right?

On the 77 if you go to the sending unit and pull the ohms wire off the sender the fuel gauge should go to full. Then ground it out it should go to empty. Now if you really wanted to test the gauge at the tank… an even better test would be to find a turn signal flasher and test the ohm’s from terminal to terminal. Then place two jumper wires on this flasher... place one end to the ohms wire that would go on the sender and the other end to ground. This should produce around 50-60 ohms of resistance and the gauge should move to maybe close to 3/4 of a tank.

If you do these test and the gauge doesn't function as described, then the issue is the dash unit... But if you do these test then tell me the results we can narrow it down quickly. The step by step testing of the entire circuit can be found on the link I've posted below. It too should help you find the issue quickly.

I am going to do a video of this soon… it is such an easy test and an easy way to know if the dash unit is the problem.

You can see different gauge test by watching this video, The title says 1968-1976 but the 1977-1982 test is done the same way, as is the operation of the gauge.



or going to our website and reading this document.

Corvette Fuel Gauge and Sending Unit Testing 1977-1982

Willcox

B. Figueroa

Thank you again for the gauge information on my 77 Vette. I performed tests #1 and 2 on the temperature gauge and the fuel gauge. Both gauges passed both tests according to the video. I did notice that I do not have a insulating washer on the 3 O'clock stud on the fuel gauge, I have insulating washers on the 12 and the 6 O'clock studs. Is this correct on the 77 Vette ? I should have a correct Delco water temp sending unit by tomorrow. As of right now my temp gauge reads about 150 at operating temp w an after market sending unit. Always appreciate any advise you may have. Thank you.

0Willcox Corvette

If the delco sender reads correctly it will be the 8th wonder of the world.. lol.. I hope it does.. but would not take the spread on this one.

B. Figueroa

I was hoping someone could tell me if the 1977 Fuel gauge has
insulating washers on the 12 o clock and 6 o' clock terminals