Spurting fuel when starting engine

B

baz

Well-known member
Joined
Jun 19, 2009
Messages
6,083
Fluid Motion Model
C-24 C
Today I topped up my 75 gallon R25's diesel fuel tank. It was at 67% full (per the Yanmar display) before fueling so I had calculated it needed some 24.75 gallons to be topped up. I filled the tank with 25 gallons and there was no issue so I kept pumping and eventually stopped at 33.325 gallons as the pump shutoff just as it does when filling a car's fuel tank. The extra 8.325 gallons presumably was due to the error in the Yanmar fuel tank display gauge reading.

After fueling and replacing the fuel filler necks spin on cap and wanting to leave the fuel dock I started the engine and went back to the stern tie to release it. At this point I noticed red dyed diesel on the swim step that appeared to have spurted out of the fuel tank's relief port. It was not that much but enough to catch my eye. I mopped it all up as well as some on the transom surface.

Questions:

1) Why did this happen when starting the engine ?

2) When starting the engine is the fuel tank in any way pressurized causing a very full fuel tank to spurt some fuel through the relief port ?

3) How do others know when their fuel tank is full ? I've been told to listen for the air whistling from the relief port and when it reaches a high frequency to stop fueling!

4) Just how accurate is the Yanmar fuel gauge display ? A 1% error equates to 0.75 gallons and a 10% error would then mean 7.5 gallons which is approximately the extra fuel beyond my calculated 25 gallons. I have a hard time thinking the Yanmar fuel gauge is anywhere close to being 10% in error mind you.
 
Not from a Ranger/Yanmar perspective, but from plenty of time on boats... I've yet to find a fuel display that I would bet on. Our C-Dory is Honda powered, and the Navman fuel flow meter is more accurate than the Honda fuel gauge. I have always fueled boats until I hear a change in pitch in the sound in the fuel line/filler. If fueled 'till it clicks off (like on a car), I get fuel out the vent. Which means fuel in the water. Which means a potentially BIG problem.

With a full tank, a shift in weight, such as walking to the back of the boat, can be enough to push fuel out the vent... which can potentially draw more fuel out with a siphoning effect.

We had a fuel spill here at the marina where I am working this summer. Well, not WE, but rather a boat that fueled on land and then backed down the ramp... the change in level caused about 5 gallons of fuel to spill out that boats vent before he figured out what was going on... and hauled ass out of there. We didn't catch the guy, but we did spend a lot of $$ on booms, man hours and clean up for the mess he left.

I don't fuel until it clicks off when on a boat. If you have your engine hours and know your average fuel burn, it's pretty easy to keep track of how much fuel you should use.

Good thread. Thanks for bringing this up.

Best wishes,
Jim B.
 
Diesel systems have a fuel return . I suspect that is where the pressure comes from . If you were way topped off , it may have caused the fuel to exit the vent .
This article is a pretty informative overall picture of a modern diesel fuel system .
The tank has a sender in it and it is not exact at all . Its usually a float with a rheostat type device and it can be affected by the angle of the boat and which side of the tank its on .They are not as accurate as the engines computer if Its a common rail system. Some need to be calibrated to the tank's size .
Marc
 
You could have a sag in your fuel vent line. Fuel gets trapped in the low area from by the boat being tipped back, from heavy seas, a ramp, or overloading and then is forced out by air pressure when refueling. Just a thought.
 
We find that when fueling our R-25 (2008) there is a continuous sputter of fuel out of the vent. I do not understand why this should happen and it is not much but to limit the effect on the water we have help and absorbent cloth at the vent to catch the spill. When we filled this week we also stopped filling based on how much we thought the tank would hold. Ended up that the tank guage said the tank was less than full. Since fuel is readily available on the Columbia River in Portland a tank that is less than full is not a problem. I suspect we would want to have a full tank when we get to the Puget Sound so I also need to figure out how to determine when the tank is full. Anyone have an idea why we get the fuel sputter while fueling?
Good information about a tank that was filled on land that spilled fuel when the boat was launched. I will make sure not to overfill my tank before launch.
John Turner, John's Folly
 
Fuel gages cannot be relied on. :roll: :cry: With the R21EC, one can see the fuel level in the tank. At my last refueling, I filled the tank to the line near the top of the tank, as usual. The fuel gage read slightly over half full. It normally read full. Boat movement didn't change the reading, but it has gone down as the fuel is used. Maybe the float is fuel soaked, or stuck? 😱

A fuel spill can result in a fine of up to $854,400.00 (or more?). It just went up and my insurance coverage was increased to cover it.

Most of the sputtering/spurting problems are due to the fuel venting systems. The remainder are due to improper filling. The normal fuel vent sytem on the R21EC is impossible/horrible. :evil: Thanks to Jeff and Andrew, my venting system is much better. I removed the original vent sytem, replaced the fitting at the tank, ran a new vent line across the boat to the starboard side (making sure it was supported to prevent any accumulation of fuel, ie. always going upward, had to install a different exterior vent fitting to make sure the vent line pointed up and finally replaced the screw-on fuel filler cap and assembly with a new filler cap and assembly that are flush mounted. Only one slight stain since, maybe two drops of fuel out the vent. 😀

I recently purchased a CS30 sailboat; the fuel tank is roughly three feet below the hull exit point for the vent fitting. I expect it will be difficult to get any fuel out that vent. But, if I'm not careful I know I can get blowby from the filler. Almost all vent lines are too small to allow rapid filling.

Gene
 
If the fuel vent system on the R21EC is terrible and Jeff and Andrew helped you with your design change, why don't they change the current design? I love the boats and am looking at the R21EC as an option. Considering that this is my first boat that I will have owned, I joined this site and am constantly monitoring the input in order to feel I am making an informed decision before I purchase.
I guess I feel that like everything else in life if we find something that will improve the situation, why not change it.
Just voicing my opinion.
Pete Cameron
 
When we fill Island Ranger, somes times we get fuel sputtering out of the vent, other times it does not. I think it has to do with how much air is getting mixed in with the fuel when filling. I don't know if it has anything to do with whether the pump is gravity feed (many of the pumps up north) or it is really a pump, and how much pressure is behind it. It seems to happen randomly.....

My solution is to use a recovery cup over the fuel vent. Several Marinas here have them available, I carry one with me all the time. Using miles travelled and hours run, I can almost always outguess how many gallons I'll need. And yes, I just use the gurgling sound to know when full. I then pour the recovered fuel into the Wallas tank....

I know some of the newer R-25's vents are located in places where the recovery cup doesn't work.

Mac
 
Hi Pete,

To put the whole thing into proper perspective... I've owned lots of boats over the past 40 years and other than portable tank outboard boats, I don't think I can think of one that didn't spit out the fuel vent if filled too fast, or too full. It seems to be a problem on any boat with a built-in tank. My current boat ( '05 R-21 classic ) doesn't have an external vent, just a vented filler cap and I don't think it's ever lost more than drop or two since I've owned it.
The number of items for sale that are designed to prevent, reduce, catch, collect, re-direct and otherwise solve the "spurt" problem would seem to indicate a very sizeable market with the same problem. Almost all vent systems are designed for gas powered, rather than diesel powered boats, and are concerned with removing explosive fumes. A diesel vent could be run to collection jar(tank?) onboard rather than overboard without any danger.
 
One would think that the penalties for fuel spills and the concern for the environment would cause there to be some ruling on boat manufacturers to install devices that warn the boat owner that the fuel tank is full and to stop pumping.

BTW -- we had a blind man working at my office a number of years ago and I would see him drinking his coffee at times. I wondered how he knew when his coffee cup was close to being full. So I watched him one day to see how he managed that. Amazingly enough it was very simple (and no, he did NOT dip his finger in the coffee cup 😉 ). He had a small gadget/device that he hung over the lip of the coffee cup and held onto it and when the coffee liquid filled the cup and eventually contacted this device it vibrated, at which point he stopped pouring. I wonder if a similar device could be used for the boats. :roll:
 
Even todays cars can be overfilled until they spill fuel, that's why the pumps have signs warning against "topping off". The main difference is, they won't fine you so much that you could loose your home and 401k if you spill a little gas. Even if that spill will wind up in the waterways via runoff through the storm sewers.

A device to detect a boats fuel level before it overfills would have a few problems to overcome;
Firstly, it can't use anything electrical in contact with the fuel or fumes (remember it needs to be compatable with gasoline)...so no sparks or chance of sparks...ever.
Secondly, it must be set to work at all levels of list, pitch or yaw so it would need to be located well below where most folks would consider the tank as "full". Human nature would result in the "alarm" being ignored or dis-connected.
Thirdly, it would need to be abolutely, positively, 100%, definitely, for certain to ALWAYS work to foolproof perfection...forever. Otherwise whomever made it, or sold it, would be liable for massive lawsuits.

Probably best to always under fill and carry a 5 gal can if fuel load is that critical
And if it spurts fuel "when you do it that way"...then... "don't do it that way"

All this makes me appreciate the "fill-directly-into-the-tank-that-the-fuel-level-is-visible-through-so-I-can't-over-fill-it-system" that the R-21 used.
 
There is a device that can be added to the vent line which will give an audible alarm as the fuel tank is beigning filled.
When the sound stops, stop filling.
I had that on my gas powered boat and no more fuel out the vent.
The faster the fuel is added to the tank the louder mthe sound.
One source is:
http://www.greenboatstuff.com/grmafuwh.html
Bill
 
Pete, one would have to ask Jeff and Andrew why Ranger doesn't change the vent system on the R21EC. 🙂 Perhaps they don't agree with my opinion about the vent system in use. 😉 Actually, I was surprised when I checked a 2010 R21EC at the 2010 Atlanta Boat Show and found it had the same vent system as my initial one. :? One problem with the original system is the distance from the vent fitting on tank to the external vent fitting is extremely short. So short, my vent line was kinked, further restrictng air flow. The tank would pressurize when the fuel was sloshing around due to wave action and blow fuel thru the filler cap outlet and thru the vent. :cry:

One issue with fuel venting systems has to do with allowing the air in the tank to be displaced by the incoming fuel at an even rate. And, having the tank far enough from the external vent fitting to keep fuel within the tank and the vent line when fuel is sloshing around. Baffles in a fuel tank can help. Larger venting capacity can help. Being careful when refueling is important.

When I considered buying a R21EC, I looked at a new 2008 model. At that time there was only one fuel filter in the system, the one on the engine. I brought that to the attention of the dealer. Ranger then began installing the primary fuel filters in the aft storage area and I think they also retro-fitted the 2008 models still in the dealer system.

Ranger is very, very good about taking care of their customers. Probably the best company I've dealt with in over 50 years of boating. You won't get a perfect boat from anyone. The R21EC is an excellent boat. But, one needs to understand what it is that one is buying. This forum can help one gain that understanding.

Gene
 
I have a 2007 R25. The fuel vent is on the starboard side just below and slightly aft of the fuel fill in the center of the starboard side deck.

When I fill there is no problem until the tank is almost completely full. Then there will be sputters out the vent if I am not very careful. At the first sign of a sputter I know the tank is almost full. Not very scientific, but I have topped up the tank many times with this method.

As for the fuel guage, it is highly inaccurate. It goes down relatively quickly to half full, then seems to go very slowly the rest of the way. At leat it tells me that I have "a lot" of fuel or "very little" fuel. My habit is to top it up as often as possible when cruising rather than risk running out of fuel.

I made the mistake the first winter of leaving the tank half full. I had a lot of "dirty fuel" problems that summer and wound up installing a primary filter. Since then I keep the tank topped up, use a biocide in the winter, and things have been ok.
 
My turn 😀

The way our system is designed with the fuel tank fill and vent is pretty simple. On "Newer" models of the R25 the fuel fill and vent are very close to the same height level. If you "over fill" the tank you will have fuel not only to the top of of the fill but also the vent. The nice thing about the newer Nmea 2000 engines and Nmea 2000 electronics, you can calibrate another source to keep track of fuel since the two now talk. Another thing to realize is that diesel can foam up very easily when filling too fast which will cause fuel to "spit" out. My suggestion to all is this neat little device that I use every time I fill up my boat. http://www.thefind.com/sports/info-no-s ... ery-system

As for the R21. We have changed the fuel system on newer production built boats.
 
Got an early start on the Labor Day crowd. Ran down the lake to refuel this am. The only place on the lake with diesel fuel (to my knowledge) is a round trip of two hours at 2900 rpm, 7+ knots.

Anyway, the gage read half full (or half empty); took 8.225 gals to fill it. So the gage reading is a bit off. Used my usual technique of observing the level in the tank to know when it was full. No sputtering, spurting or splashing while refueling, even though the pump was moving fuel much faster than usual.

When finished, the gage read full. I guess the gage had stuck the last time I refueled.

Gene
 
I'm pleased to hear Ranger changed the fuel system on the newer R21ECs. Hope you did it the way you guys recommended for my boat. It has worked perfectly. 😀

Gene
 
baz":1zdjp6lf said:
...snip...

Questions:

1) Why did this happen when starting the engine ?

2) When starting the engine is the fuel tank in any way pressurized causing a very full fuel tank to spurt some fuel through the relief port ?
...snip...
Click to expand...

I appreciate all the replies to the OP. However no response seems to have answered my first two questions!

When I filled my fuel tank there was no evidence of fuel spill, yet when I started the engine fuel spurted out of the fuel vent. I have to assume this is where the fuel came from as the fuel filler cap had been screwed back so fuel could not have come from that source.
 
Andrew Custis":1cmbfznk said:
My turn 😀

The way our system is designed with the fuel tank fill and vent is pretty simple. On "Newer" models of the R25 the fuel fill and vent are very close to the same height level. If you "over fill" the tank you will have fuel not only to the top of of the fill but also the vent. The nice thing about the newer Nmea 2000 engines and Nmea 2000 electronics, you can calibrate another source to keep track of fuel since the two now talk. Another thing to realize is that diesel can foam up very easily when filling too fast which will cause fuel to "spit" out. My suggestion to all is this neat little device that I use every time I fill up my boat. http://www.thefind.com/sports/info-no-s ... ery-system

As for the R21. We have changed the fuel system on newer production built boats.
Click to expand...

Andrew: Thanks for the No-Spill-Recovery-System reference -- a cheap enough soln to fuel spills via the fuel vent opening. 🙂
 
baz,

If the tank, the vent line and rest of the fuel system were completely full, perhaps 😉 starting the engine moved enough fuel thru the fuel return line to force fuel out the tank vent, or maybe even the around the fuel filler cap. I think it's possible, but unlikely (see last paragraph).

But, somehow your system got pressurized. My experience with these sytems, diesels, indicates the pressure comes from displaced air. On my R21EC (before the Ranger recommended modifications were installed), movement of fuel within the tank would creat enough air pressure to blow fuel out both the vent and the filler cap. Installing baffles in fuel cells help to minimize this problem (I don't have baffles and won't install any, can't figure out how to do so in a plastic tank. Besides I don't need them now). Two other major causes pressurizing the system is too rapid filling and overfilling.

I overfilled one of my tanks in an Albin trawler we owned. Not enough to get fuel out of filler port, but enough to fill the line from the cap to the tank. I usually ran on one tank at a time, switching to manage fuel in each tank. I ran that the refilled tank for several hours without a problem and then switched, as usual. Several weeks later I found fluid around my rudder post. Checked everything, finally discovered fuel had leaked around the overfilled tank gage gasket, run across the top, down the side and back into the rudder area. Lesson: do not overfill, fuel will find a way out. 😱

Gene
 
You must log in or register to reply here.

  • Tugnuts.com is the community hub for Ranger Tug, Cutwater, and Solara owners. Since its inception in 2008, the Tugnuts forum has grown into an active and thriving community of more than 9,000 members. It serves as both a meeting place for the best boating community online, and an invaluable archive of information.

  • User menu
Back
Top