Hi all, I'm new to this site - first post! Today my fuel gauge read that the tank was completely empty, when it is in fact almost full. This'll be an engine-out job I'm sure, but before I go digging, does anyone have the most likely cause? It is reading as though it is totally empty (as if the ignition is off) but went up to the red mark after I'd put £35 of fuel in today Float? Sender? Gauge? Ive a 72 westy, 1600 twin port. Thanks in advance.
There is a resistance wire that the gauge uses to register an amount of fuel and this is displayed using a variable voltage. So basically the sender is a variable voltage regulator, and if there is a break in the wire, say in the middle of the resistance board, then the gauge will only register up to a certain level before it registers no more. Its hard to explain. The fuel sender is the most likely cause, however you need to check the sender wire - that sends the signal to the gauge, and you need to check the gauge works, and you need to check the voltage regulator on the gauge (if you have one) and eliminate any faulty components befoer you know which ones to replace. It is a methodical process, i have literally just done it. I had to replace all of the above. ??? Use the forum search to find other fuel gauge related topcs and you will find all of the info that you need. PSG
I had the same problem ,so i ordered a new volt regulator that plugs into the back of the fuel guage costing £39 with post ---- it wasnt the problem .This was supposedly the most likely fault i was told .I found on closer inspection that a wire on sender unit was snapped off so i replaced the sender and it worked , cost £30,plus £40 to rewire etc . I then found out that a tiny tiny wire in the guage was broke as well so rigged an old beetle fuel guage which reads backwards now but i now know i have fuel until i fit the aftermarket VDO guage i bought of ebay this week then will set up the sender to the correct level etc ,but am stuck with a volt regulator ,what a waste of money and herritage wont have it back ,live and learn.
It'll be: Broken wire in the sender Broken wire to the sender Voltage regulator broken (behind the instruments) gauge itself broken This page explains it all much better than i can: http://www.nls.net/mp/volks/htm/fuel_ga.htm if you need to get to the sender then you'll either have to drop the engine and fuel tank (some say you can drop the fuel tank without removing the engine ) or make a hatch above the fuel tank. probably best to make a hatch for future access either way. that voltage regulator is junk, mines not working properly because of the regulator at the moment. I'll figure a solid state replacement when i get round to it.. Cheers and welcome to the site. loads of clever folks on here..
Just wanted to say Thank You for your informative answers. I havent had the time to check yet, but when I do, I'll get back to you. Thanks again.
