82 Suzuki GS750E - Gas gauge / Oil Temp sender ?

[mrmach5]

Recently acquired a *82 GS750E. Fuel Gauge not working, and when removing the tank I see the sending unit has a spot for a hose.? the only two hoses I see up top are the fuel supply and the vacum petcock hose ???? Also where is the oil temp sending unit located on these?
Thanks​

 

[Rich82GS750TZ]

Welcome to the forum.
Some general greeting stuff first.
It's much appreciated around here if you make an introductory post in the GS Owners forum.
If you haven't done so already (if you can't see my signature), Go to the top right of the page and pull down your username, go to User Setting, go to the Account Tab, and look for Visible Post Elements, check the Show Signature, and Show Avatars boxes, and save your changes. You can also created a signature from that page (highly recommended). Many of us keep helpful links in our signatures, such as the fist one on mine to Bike Cliff's Website. https://gsarchive.bwringer.com/
On that site you'll find many useful resources like factory service manual and a supplement just for the '82 GS750 E & T Models. These are the 2 you need.

There's also a link in my signature about some of the better ways of posting pictures on the site.

To your specific questions:
Fuel Gauge not working: There is a wired connection to the fuel sending unit, make sure those terminals are clean and tight. The not working part has nothing to do with the missing drain hose that should be connected to the sending unit. There should be a long hose connected to this, run over the top of the carbs and down to the right side rear of the engine case, through a squarish chase where the battery drain line and airbox drain line also run, to allow these fluids out to ground off-set from the rear tire. The fuel sending unit drain line is there only for if/when the sending unit gasket leaks (hopefully never). Besides the fuel line that goes from the bigger nipple on the petcock to the rear of the carbs to a nipple between Carbs # 2 & 3, and the smaller vacuum line that runs from the smaller petcock nipple to a nipple on the front of carb body #2. you should have vent lines that run from nipples between carbs #'s1 & 2 and between #'s 3 & 4 routed up over the airbox to terminate in still air under the front of your seat. The only other hose is a short, thick one that runs from the top of the Valve Cover to the airbox to eliminate oil vapor.

Oil Temp Sensor: (this bike doesn't have one). Your bike has an oil pressure sensor poking out of the front of the oil filter cover (front of the engine, down low, red in color, should have a wire coming from it.) All that is under the dome-like piece at the top of this picture. Don't undo those nuts until you want to change your oil.