Engine dies when using port tank

T

tparrent

New member
I was out exploring the industrial rivers of New Jersey yesterday (hey, you boat where you can when you can) and had a wee problem with my engine.

The Honda 90 has been flawless to date and only has 60 hours on it (2007 C22)

With the engine running, I switched from the starboard to the port tank. The engine ran fine for five minutes then quit. Of course it quit under a bridge as another much larger vessel was coming through. No sense in it quitting in the quiet marsh with nice soft shores to drift into!

I switched back to the starboard tank and was able to restart the engine. As I had let the starboard tank run low, this led to a little excitement with a container ship and three tugs in a tidal race but that's a different story...

When I got back to the dock, I switched to the port tank again and ran it for five minutes with no problem.

This morning, I headed out again using the port tank. After about ten minutes, it quit. Of course it chose a tight spot at the marina exit with a big tour boat coming up behind me.

I switched back to starboard and the engine ran fine.

The fuel in both tanks has almost always come from the same pumps so I would be surprised if the fuel itself was bad.

Do you shut down the engine before switching tanks? Do you have to prime the fuel line when switching?

Where do you think the fuel came from that kept the engine going for five or ten minutes?

Thanks

Tom
 
That sucks, which is almost certainly the problem. It sounds like your tank vent is plugged. It draws fuel out until the tank vacuum is greater than the pump vacuum and it quits.
 
Tom, I would suspect the tank, pick up, or line from tank to fuel switch. You may want to pull the fascia board, then do some inspecting. Your vent on the port side could also be blocked, I'd check that first.
 
I am not qualified to answer any of your technical problems but I certainly can relate to your experience that things don't seem to break until the most inopportune times! Why is that??????
 
It doesn't sound like this is probably the issue, but, just in case.. (since the engine can run a fair while on residual fuel, and "five minutes" could maybe be four minutes, etc.)... have you checked previously about whether your tank valve labeling is correct?

Reason I say that is that I have read a few threads here wherein people reported that the pointer and the label don't always agree on the function (so pointer to port could be "off"). Maybe you have already checked yours or previously determined that the pointer is correct though.

(Because of reading those older threads I checked mine before connecting the new fuel hoses and it did read correctly as originally plumbed, so at least some of them do.)
 
Is this something new? Is there a possibility that the fuel transfer switch is being turned to the wrong position (sometimes the handle vs the pointer is an issue).

Certainly you want to check the vents. But also use the primer bulb to see if you can bring fuel from the tank into the filter. It could be an obstruction at a fitting in the fuel line also. Could be an anti siphon valve, could be obstruction on the pick up screen. could be an air leak at some place in the system on the port fuel line. If it is not obvious such as the vent--then blow compressed air back thru the line, and start tracing each fitting. Once I found a bad antisiphon valve, another an air leak, a third time it was some teflon tape which was on one of the fittings, acting like a butter fly valve.
 
Thanks for all of the suggestions.

I will definitely check the vent first.

Now that you mention the hoses, I recall that there has been one change that could have caused the problem. I replaced a perfectly good bilge pump awhile back (turns out it was only blown fuse :amgry ) and in doing so I had to remove the batteries and completely clear the area. I'm not sure exactly where the fuel lines run but they must be in that area somewhere - and it would only be the port tank fuel line that would cross over to the switch on the starboard side.

My trip yesterday was the first time I used the port tank since the bilge pump replacement. I will look up under there and see if I might have jostled something or pinched the hose.
 
It seems like it is the fuel pick up in the tank that has the problem. As thataway mentioned the fuel pick up can get clogged by debris or corrosion. The pick up can be easily changed with a new one at West Marine or any other boat store.

Or else it could be the check valve is stuck (at the top of the tank) that keeps fuel from backing up from the motor. In either case, just remove the entire fuel pickup/ check valve and replace them with new parts.
 
This topic is so timely. On our future cruise from Daytona to St. Augustine, I believe some 56 or so miles I figured I would have to switch tanks. The 16 comes with two 6 gallon tanks or say about 72 miles worth of travel. Going in a group and am not sure if they plan to make a "pit stop" half way. I figure we would have to stop turn off the engine switch the lines from the tanks and re-start. Does that sound right?
 
Stan-

No need to turn off the engine, IMHO.

Modern fuel line to tank connectors have check valves built into the connectors that will stop loss of significant amounts of of fuel when switching tanks.

I would have a rag handy to wipe up the very small amount of fuel that may spill when switching.

The same amount, maybe 1/4 of a teaspoon (1-2 cc), will happen whether you have the motor running or shut off.

The motor can continue to idle while you switch tanks. It will not run out of fuel while you're doing so.

Not a big deal (!)

Have a nice trip!

Joe. :teeth :thup
 
Just as another data point: I switched tanks a half dozen times or so when underway on my last (first!) trip, and nary a hickup. I think that the engine will run so long with no fuel hooked up (i.e. if you take off a line to run one dry) that by the same token, any momentary blip caused by switching tanks is just "taken up" in the overall flow (by the time it actually reaches the carb or injectors).

Now I need to find out if it's possible to lube the selector valve or if a stiff/creaky one just needs to be replaced...
 
Now I need to find out if it's possible to lube the selector valve or if a stiff/creaky one just needs to be replaced..
Click to expand...

I would use Dupont multi use Teflon liquid lubricant in the dropper bottle.
The best way would be to take a hose off, and expose the valve interior. As you rotate the valve thru 360 degrees, you should see the sides of the interior of the valve exposed in two positions. Drop a few drops of the lubricant on the exposed sides of the valve, and then rotate it a number of times. Work the valve a number of times. These do need exercise.
 
Thanks for the reply on the valve lubing. I had the hoses off last summer (I replaced all my fuel lines), so I guess I should have lubed the selector then... duh! I did lube the part near the handle, but then (later) discovered that didn't do the trick. I'm actually not sure if they are ball valves or not - it's the "standard" valve that I see on many 22's (the one where the handle looks like it should be the pointer but instead it's a tiny pointer opposite the handle). I'll take a closer look at it when I'm reunited with the boat. I either need to lube it or replace it. It works fine but I don't like to wince every time I use it (as it kind of "squeaks").
 
tparrent: When I first got my boat and wasn't familiar with the fuel selector switch, I had the same problem as you describe. Turned out to be the detent, on the selector for the port tank was marked in the wrong place. So, after running long enough to starve for fuel, the engine would die. The indication on my boat was that the fuel bulb between the motor and selector valve was partially collapsed.
 
I did something similar this past weekend.I moved the selector to the other tank and it ran fine for a few minutes then out of gas died.I had the winter canvas on ,so instead of looking at the pointer I just reached thru the canvas and moved it to were it clicked. The only problem was I pointed it to OFF instead of port.I looked at the bulb and it had collapsed, so switched it back to original side and lo and behold,the bulb filled immediately once it could suck fuel again.Big relief.. :smileo
 
We experienced a similar problem this past summer with the port tank. After several occasions of water showing up in the Racor and slowing fuel flow I think we finally found the problem. Filling up the water tank with a hose was the problem. Some water would spill from the process of filling the water tank and migrate to the stern along the rub rail. The water ran to the low spot on the rail and dripped off, right on the port vent. Water tension and the lack of a trap allowed enough quantity quantity of water to contaminate the port tank fuel and cause the Racor to slow fuel flow to the Honda 90. This water was observed entering the tank via the fuel vent while on the trailer with the tongue jack all the way up.

The solution was to pump the tank dry. Then changed the fuel vent to a vent with a small trap and a new fuel vent hose. So far so good.
 
Speaking of the "Racor". How often does that get cleaned, emptied, changed out. Is there some sort of filter in there that should be replaced. On the 16 it is located in a place where one does not see it and can easily be forgotten about which I'm sure is not a good thing.
 
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