View Full Version : possible bad float at fuel level sender 84 SS, also bouncing oil pressure guage

10-09-2012, 10:16 PM
I'm guessing it is based on the symptoms. I've not dug into it yet. I know that when the tank is full, the gauge lags behind the truth, and in fact it never rises to the full mark (and I know the tank is full). Guessing that the float is no longer floating. So the question is, if it is a bad float, where do I get a replacement? I know the MC dealer here would just laugh. I see a part on skidim but dunno if it is correct for my boat -- just says for tanks that are 10 inches deep, and this one is about that or maybe even 12 inches.

Oil pressure gauge bounces around a bit (erratically). It's not so bad that I can't rely on the accuracy of the gauge. I'm guessing a bad ground? I've seen my bimmer temp gauge do that when the ground nut came undone from the gauge. Anyways would that be the likely cause or could it be a bad sender?

10-09-2012, 11:38 PM

Check out this post it may help.

You can get fuel senders of different lengths also. If the tank is 12 inches you would want a sender that is at least 1 inch shorter.

Oil pressure sender maybe bad. Does the needle bounce with the boat moving and stay still at idle? If so it could be the gauge also. Measure the resistance from the sender to ground then get a resistor the same from radio shack equal to that value. Connect it to the sender wire on one end and ground the other end of the resistor. This will give it a fixed value so if the gauge still bounces it is probably a bad guage.

10-10-2012, 12:23 AM
The fuel tank sending unit I put in my '77 this year was adjustable for depth of tank. I got it through Amazon. I will take a look at the packaging in the morning as it is still in my garage.

10-10-2012, 08:03 AM
You can buy direct and save a few if you need a new one... http://www.wemausa.com/

10-10-2012, 11:18 AM
[QUOTE=strad;883383]...Oil pressure gauge bounces around a bit (erratically). It's not so bad that I can't rely on the accuracy of the gauge...QUOTE]

I had an Oil Sender do that once. Was a bad/dirty connection at the sender. Unconnecting and reconnecting several times fixed it.

Could also be the guage.

10-10-2012, 11:29 AM
A couple threads on Oil Pressure Sender with good information: