Re: Randy

Posted by HH56 On 2022/5/16 17:40:30

On your new sender it could need a combination of both checked because the actual resistance housing, location, and swing arc may be different than the stock sender. Hopefully your vendor had an old sender or tank depth to work with when they built it and everything is already set up.

If you are replacing a sender with the same basic housing shape and the resistance is located in the same plane as the original as is the case with the proper Ford unit, then there is a fixed arc where empty will be at one end stop on the resistance unit and full at the other. The arm length is calculated so when the arm touches the resistance unit end stop at the empty end the float is just above the bottom of the tank and at the other end stop, just below the top of the tank.

The fine height adjustment is typically done by the bend which also accommodates where the arc is positioned if senders are different. Packards sender arc is out to the side with a slight bend but one Ford unit I have is pointing down so the arm has a 90 degree bend to position and extend the float to the side.

The bend can accommodate some difference but not enough if the arm is short and the arc is made and stops are reached before the float does a full travel. If the bend is adjusted say at the empty end so the float is at the botttom and gauge reads empty then If the arm is too short the arm will reach the full end stop too soon -- way before the float is close to the top of the tank so gauge will read full at some lesser amount and stays that way until the tank level drops enough the float can move. Too long an arm, the float will touch the tank top before the resistance arc is complete and end stop is reached so even with a full tank the gauge will read less than full.