Fuel Gauge stuck on full! - SailNet Community
 2Likes
Reply
 
LinkBack Thread Tools
post #1 of 16 Old 04-12-2016 Thread Starter
Senior Member
 
Join Date: Feb 2016
Posts: 146
Thanks: 7
Thanked 8 Times in 8 Posts
Rep Power: 4
 
Fuel Gauge stuck on full!

I've always carried with me the idea that the fuel gauges on sailboats are often wonky or downright inaccurate, so I record and track my engine hours and fuel usage and this has served me well, but the gauge on my 2004 B323's tank is pegged to full all the time and doesn't budge.

Is there any fix? How easy/hard/cheap/expensive is it to address?

Thanks in advance for any replies.
Skyeterrier is offline  
Sponsored Links
Advertisement
 
post #2 of 16 Old 04-12-2016
Senior Member
 
Join Date: Feb 2011
Location: San Francisco Bay area
Posts: 3,183
Thanks: 9
Thanked 92 Times in 91 Posts
Rep Power: 9
 
Re: Fuel Gauge stuck on full!

What's a fuel gauge?
oysterman23 likes this.

Bristol 31.1, San Francisco Bay
MarkSF is offline  
post #3 of 16 Old 04-12-2016
Senior Member
 
Stu Jackson's Avatar
 
Join Date: Jul 2001
Posts: 1,167
Thanks: 0
Thanked 32 Times in 31 Posts
Rep Power: 19
 
Re: Fuel Gauge stuck on full!

Good idea to use engine hours for the reasons you stated.

A pegged gauge is either of two things: the sender or the gauge. It's usually the sender. Sometimes a bad ground can cause it.

Check it out: I'd first confirm the ground (I once found a ground wire simply hanging in space because a butt connector failed!!!), then the sender, although sometimes it's easier to check the gauge.

How to check the gauge: Google Teleflex, they have troubleshooting guides for just this issue.

Stu Jackson, Catalina 34, 1986, M25 engine, Rocna 10 (22#), Maple Bay, BC, Canada
Stu Jackson is offline  
 
post #4 of 16 Old 04-12-2016 Thread Starter
Senior Member
 
Join Date: Feb 2016
Posts: 146
Thanks: 7
Thanked 8 Times in 8 Posts
Rep Power: 4
 
Re: Fuel Gauge stuck on full!

Quote:
Originally Posted by Stu Jackson View Post
Good idea to use engine hours for the reasons you stated.

A pegged gauge is either of two things: the sender or the gauge. It's usually the sender. Sometimes a bad ground can cause it.

Check it out: I'd first confirm the ground (I once found a ground wire simply hanging in space because a butt connector failed!!!), then the sender, although sometimes it's easier to check the gauge.

How to check the gauge: Google Teleflex, they have troubleshooting guides for just this issue.
Thanks, I'll look into this. I've been told that even the fuel gauges on small private aircraft are none too accurate either.
Skyeterrier is offline  
post #5 of 16 Old 04-12-2016
Senior Member
 
JimsCAL's Avatar
 
Join Date: May 2007
Location: Glen Cove, NY
Posts: 4,523
Thanks: 5
Thanked 205 Times in 197 Posts
Rep Power: 13
 
Re: Fuel Gauge stuck on full!

This is easy to trouble shoot with a Digital Multimeter. The sender is just a variable resistor moved by a float and the gauge measures DC volts. The voltage at the gauge changes as the resistance of the sender changes as the float moves up and down with the fuel level.

Accuracy can be pretty good if properly set up in a rectangular tank.
JimsCAL is online now  
post #6 of 16 Old 04-13-2016
Badger Sailor
 
MSN2Travelers's Avatar
 
Join Date: Sep 2006
Location: Milwaukee
Posts: 189
Thanks: 1
Thanked 7 Times in 6 Posts
Rep Power: 14
 
Re: Fuel Gauge stuck on full!

My `99 Oceanis 352 was pegged full when I took delivery from the broker. Yes, I ran out of fuel on the 110 mile trip to homeport.

My fuel gage is made by VDO. Their system has the gage pegged full if there is an open in the circuit and pegged empty if there is a short. A quick test is to disconnect the wire at the sending unit. The gage should be pegged full. Ground that wire and the gage should drop below empty.

If this happens, look at the sending unit and/or the tank ground. If you pull the tank sending unit, an ohm meter should read 10 ohms empty and 180 ohms full.

It is common for the connections in the circuit to corrode at the back of the gage, the connection at the sending unit, the ground from the tank/sending unit or all of the above. Look to your connections first before you start throwing money at the problem.
eherlihy likes this.

Paul
`99 Beneteau Oceanis 352, #282 WiTCHCRAFT
Milwaukee, WI
Sailing Lake Michigan and the Great Lakes
MSN2Travelers is offline  
post #7 of 16 Old 04-15-2016
Senior Member
 
Join Date: Feb 2010
Location: Narragansett Bay
Posts: 20,343
Thanks: 82
Thanked 577 Times in 553 Posts
Rep Power: 11
   
Re: Fuel Gauge stuck on full!

Quote:
Originally Posted by Skyeterrier View Post
......I've been told that even the fuel gauges on small private aircraft are none too accurate either.
This is true, although, they are required to be accurate in the low reserve range and at full. In between is where they get sketchy for a variety of reasons.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeanneau 54DS

In the harsh marine environment, something is always in need of repair. Margaritas fix everything.
Minnewaska is offline  
post #8 of 16 Old 04-15-2016
Senior Member
 
outbound's Avatar
 
Join Date: Dec 2012
Location: NE & Windwards
Posts: 6,392
Thanks: 137
Thanked 190 Times in 181 Posts
Rep Power: 8
 
Re: Fuel Gauge stuck on full!

Have four fuel tanks so log gives no assessment of what's in a particular tank. Therefore spec'd dip sticks for every tank in the boat (8-2 waste, 2 water, 4 fuel). Dipsticks never fail. May wish to install a dipstick as you work through this problem. KISS redundancy. Paper towel and dipstick = true info.

s/v Hippocampus
Outbound 46
outbound is offline  
post #9 of 16 Old 04-15-2016
Senior Member
 
Join Date: Feb 2010
Location: Narragansett Bay
Posts: 20,343
Thanks: 82
Thanked 577 Times in 553 Posts
Rep Power: 11
   
Re: Fuel Gauge stuck on full!

A holding tank dip stick?

My holding tank is now made of poly (I had it custom re-built a few years back), so I can see it visually, if necessary. I also find the gauges for poly that can use external tape sensors to be a bit more reliable than the interior mechanical ones, but still not perfect.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Jeanneau 54DS

In the harsh marine environment, something is always in need of repair. Margaritas fix everything.
Minnewaska is offline  
post #10 of 16 Old 04-15-2016
Learning the HARD way...
 
eherlihy's Avatar
 
Join Date: Jan 2007
Location: Boston / Ft Myers Area
Posts: 6,843
Thanks: 396
Thanked 296 Times in 291 Posts
Rep Power: 13
 
Re: Fuel Gauge stuck on full!

Paul's post is spot on!
Gauge pegged full = open circuit on the sender wire.
Gauge pegged empty = sender wire with low (or no) resistance to ground.

A quick check is to start at the tank, and touch the sender wire (pink) to a known good ground. Do not assume that the tank is grounded until you check it. When touching the sender wire to ground, the gauge needle should fall to empty.

I will also add that both the gauge and the tank need to be connected to ground, in addition to having the sender wire connect them. A long time ago I installed a new fuel gauge, and ASSumed that the sender wire would provide ground to the gauge. I was mistaken, and the gauge stayed pegged all the time. Two gauges and one sender later, I figured it out.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

USCG Licensed OUPV Captain, ASA 101/103/104/105/106/114/118 Instructor - Also certified in Marine Electrical Systems


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
eherlihy is online now  
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
adding a fuel gauge Skipper Jer Diesel 7 05-07-2016 08:58 PM
Diesel Fuel Gauge SawWhet Diesel 4 08-20-2011 09:41 AM
fuel gauge -- any suggestions? pegasus1457 Diesel 24 11-28-2009 04:01 PM
Fuel Gauge Morgan 30 Twoowls Gear & Maintenance 8 11-18-2009 03:02 AM
Fuel Gauge questions rikhall Gear & Maintenance 20 01-02-2009 11:22 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome