New fuel senders

davidbrooks

I thought i would open a new discussion on this topic.  We started a previous one and @LaRea made an interesting comment when he said that the OEM senders just read in 5 increments.  I have been having some flaky experiences with my setup so i had been looking into a solution.  Well, this weekend it rose to the top of the priority list.  I was taking the boat to the marina to start winterizing and ran out of gas.  I was about a mile away when i ran out.  
Called TowBoatUS and waited to have them come get me.  If you all don't have a towing service i recommend it for peace of mind.  I have had this since 2018 and never had to use it.  My fuel senders are original.  They are just an analog resistance sender that is basically a rubber ball on an arm.  The sender is wired into both power and a Garmin NMEA 2K device.  The setup has been problematic since day one.  Getting it calibrated...keeping it from just dropping out of the system...you name it i seem to be fiddling with my starboard tank setup all the time.  I didn't have a long run, havent used the boat hardly at all this year.  So, i figured i would just rely that the one sender that was working had an equal amount in the other tank ~ 30%.  That assumption got me about 85% of the way to the marina.

Tied up to the fuel dock for the night and put 20 gal in each tank. Took a while for the engines to get primed but they thankfully started right up. I pulled out the icemaker and fridge to get to the starboard tank.  BTW on a 2003 342 they put in 117 gallon tanks.  For anyone in the future that wants to know they are Florida Marine Tanks, FMT-117P-RKB  117G/442L  Part number 240126.  



I am going to put in NMEA 2k senders.  I ordered Oceanic Systems NMEA 2000 Fuel Tank Volume / Level Sender - 1000mm - 5-Bolt SAE from defender.com. Link here.  I am interested in if anyone can find any bad reviews or has any warnings for me.  I looked but couldn't find anything.  

The reasons i settled in on these are: 1) reputation 2) all one unit 3) no mechanical arms 4) can be shortened and calibrated on site 5) have up to a hundred increments vs 5 6) they also will sense if there is water in the tank.

The plan is to shorten the pickup tube to 24 inches.  The tank is 28 inches deep and i can assure you the pickup tube goes all the way to the bottom.  When i put in 20 gal i measured 4 inches of fuel at the bottom of the tank.  I figure if the sender is reading empty i can still have a few miles left.  It may take a while for them to come in though as all of the sites say they are backordered.

 

Dream_Inn

I'll be following this topic to see how well the new senders work.  For now, I will continue going off of my fuel burn from vessel view and watch my analog gauges.

Were you on the south river in that picture?  Just FYI, but tow BoatUS will also bring you fuel.  (I had this happen 300 yards away from my destination - fuel burn was way off due to bad plugs- & they brought me 25 gallons of fuel).  Did you run out of fuel on one tank first & then the other?  Glad you got it back up and running ok.

davidbrooks

@Dream_Inn I was on the Severn River right around the Rt50 bridge.  I lost the first engine about 3-400 yards South of the bridge and then lost the second engine 400 yds North of the bridge.  I stopped and opened up the valve to see if i could get them running off of one tank but sucked that one dry in minutes.  I was so close to the marina that it was just as easy to have them tow me in.  It was a nice afternoon/night so all in all not too bad.  I can say though that had the weather been bad this would of been a completely different experience.  I put exactly 20 gal in both tanks and after i got it up and running the port tank read 38% and starboard tank read 46%.  That sealed the deal for me.  I am going to try and suck out the remaining fuel in each tank to see if there is any crud in the tank i need to clean out.  Knowing the pickup lines go all the way to the bottom now solidified that being a good idea.

davidbrooks

Oh almost forgot to mention that while i was sitting there waiting on a tow i had the radio on just in case i needed to reach out to someone.  Just sitting there on channel 16 listening.  Every 30 min an announcement would come on to warn boaters in the Annapolis area that "there was a submarine in the area that was covered by a protected zone of 500 ft and do NOT attempt to cross its bow".  I was just thinking so exactly what do i do if i see a sub heading to me and i am just sitting there anchored.  

YYZRC

@davidbrooks why shorten the pick up tubes?  Just curious. 

davidbrooks

@YYZRC I am not shortening the pickup tubes.  Shortening the tube on the sender.  It pulls fuel up into a tube vs having a float.  This helps with movement of the fluid and less moving parts.  I was thinking i would shorten the tube so that when the guages read empty i would still have ~20 gal left over.

YYZRC

Ok yes makes sense! You will have a “reserve” so to speak. Smart. 

When I set up my VesselView on my old boat, I accomplished the same by inputting the tank capacity as being lower than it is in reality. 

TonyG13

YYZRC said:

Ok yes makes sense! You will have a “reserve” so to speak. Smart. 

When I set up my VesselView on my old boat, I accomplished the same by inputting the tank capacity as being lower than it is in reality. 

Did the same thing on ours.

LaRea

I see the logic of shortening the tube to have a built-in fuel reserve, but I wouldn't do it.  

Why?  You can't rely on the reserve unless you know when the gauge start reading zero.  Suppose you look down and notice the gauge says zero.  When did it hit zero?  Do you have actually have 20 gallons left, or are you empty?  

In fact, I'd argue that when you're down to the last 20 gallons, that's the most important time to have accurate measurements.  I wouldn't discard that information.  

Dream_Inn

I agree with @Larea , the bottom portion is actually where I'd want my 100 increments because that is when you care the most.  I just redid my son's fuel tank on his boat and made sure it was accurate all the way to the bottom.

davidbrooks

Knowing that the pickup lines go all the way to the bottom i am not sure i agree.  I would rather the fuel guage read 0 and still have a little extra just in case.  My thoughts were to setup the guage and sender as if it is a 100 gal tank vs a 117 gal tank. I agree i want it to be accurate.  That jump from 28% remaining to engine sputtering is not a fun thing.  

LaRea

Personal preference for sure.  If I hit bad weather and use more fuel than expected, I don't want to be guessing about how much fuel is left.  

Liberty44140

This is why I do like to top off my tanks at least once a summer. As far as I know my gauges are accurate, but by filling them up all the way and loosely monitoring my hours/miles I have a pretty good idea of where I really am regardless of the gauges. 

goalie59

davidbrooks    Once you get your senders straightened around why does it matter. In my opinion (for what it’s worth) if you follow the 1/3 1/3 1/3 rule then any measurement below 1/3 would be redundant. I have always tried to follow that rule but I do understand that there maybe unforeseen circumstances that could alter that. We all pretty well know how much range our boats have from full and if you think you are surpassing that then it’s time to fill up. Just my opinion. 

Dream_Inn

It is surprising how well the pickup pulls almost every drop out of the tank.  I emptied a tank this summer (again, my son's 20 grady white) and it got all but maybe 2 cups worth out of a 60 gal tank.  I thought it would be a gallon or two.  David, maybe you want to try it first with it set to the full tank.  You can always reduce it later if you wanted.

When I get fuel, I tend to fill the tank up.  This allows me to reset my fuel burn and start from zero again.  I know running around with full tanks isn't efficient (& she sure is like a fun toy with less than a half tank), but I go thru quite a bit of fuel to be going back and forth to the fuel dock twice as much.  @Liberty44140 you need to get that beast out for longer trips!!  Top off once a summer is definitely not enough (I know, you just get half tanks more often).  This summer was definitely shorter trips for me, but I believe I filled up at least a half dozen plus times.

davidbrooks

I got one of the senders in the mail today.  The other is backordered.  If it works half as good as it looks i will be happy.  This thing is beefy.

davidbrooks

I put the fuel sender in this weekend and am very happy with it.  Oceanic systems makes a sturdy product.  To be honest the hardest part of the whole process was figuring out the alignment of the screws on the top of the sender.  They are a 5 bolt pattern that is NOT equally spaced.  The new sender is very thick so i had to get new longer screws and i just couldn't see what i was doing. I pulled it back out, put a dab of adhesive on the cork gasket to have it stick to the sender and then just kept rotating till they all went in easily.  Easily is the key word here.  If you feel you have to force it you dont have it aligned correctly.  Get a 2 " piece of PVC that is an inch or two longer than your sender pickup, cap one end and use that to calibrate full.  The calibration process is straight forward.  There is a little dial you turn to E to calibrate empty and F to calibrate full.  It really is a lot simpler than the ones that connect to the analog senders.  I didn't have the PVC so i ended up filling up my tank.  The issue is that you then have a REALLY tiny little dial you have to put back to F and this is a whole lot easier when you aren't forced into a tight spot with a camera to make sure it is in the right spot.  I plan on getting the PVC to put in the next one. 

YYZRC

The bolt spacing is infuriating when you didn’t expect it and you are contorted trying to figure it out!

davidbrooks

I am literally lying there saying to myself "it shouldn't take an hr to put in 5 $%#$ screws". 

mbnarney

And I thought I was the only one.

Grahamu

It was important to align the sender when it was the old style float on an arm to make sure it did not come in contact with the tank walls.

memorymaker

anyone have any pics on how to get to the fuel senders on a 2001 31EC?  Also, these oceanic sensors - do they require an new gage or will the factory ones work?  Do they have any wireless one's with usb transmission?

davidbrooks

I am only aware of the standard analog type and N2K. No wireless or USB. The one I put in is N2K and no it doesn't connect to the original OEM guages of that era. You are gonna need a N2K guages or use a mfd.

rasbury

On the 270 it is actually right there with pretty easy access. I was told just yesterday to mark it before you pull it- now I know why!