No fuel shutoff at fuel tank?

[Suncatcher]

I recently purchased a new-to-me boat with a Yanmar 2GM and got brave enough (never touched a diesel before) to try some basic engine maintenance. Oil change went well. But stuck at first base with changing the fuel filters. I understand that I must first turn off the the fuel at the fuel tank but there doesn't appear to be a turnoff valve. Fuel line goes directly from the tank to the fuel filter/water separater. I'm concerned that when I remove the separater that fuel will siphon from the tank. But it's an old engine so there must be a way to do this. Any suggestions?

 

[Benny17441]

It is easy to install a fuel shut off valve. Get a fuel petcock valve appropriately sized for the fuel hose. Find an appropriate location usually where the fuel line enters the engine compartment, cut the fuel line in two and install the valve with some clamps. It does come in handy when working on the fuel system. In the past I have pulled the fuel line at the water separator and inserted a screw driver or a plug to contain the flow until I finished what I was doing.

 

[SG]

You have a supply and a return to the engine. Why do you HAVE to turn-off the supply?
Do you have a electric fuel lift pump (supplemental or otherwise)?

 

[Stu Jackson]

You have a supply and a return to the engine. Why do you HAVE to turn-off the supply?

if the tsank is above the filter and engine it will siphon, that's why. If the tank is low, no issue. He didn't say.

For the OP: Until you install one, and Benny's right, next to the fuel filter is the best place for it, use vice grips with something like a bicycle inner tube or leather for chafe, to close up the supply line.

Also, almost NONE of us knew anything about diesels until we bought our boats. You are not alone. Only exception I can think of is farmers! They grew up with tractors.

 

[Ralph Johnstone]

Does that label say "vent lines" or do I have an overactive imagination ?

I also see a crack in the rubber under the upstream gear clamp. If the tank is higher than the engine, you may eventually start pulling air into your fuel system given the brittle condition of the hose.

Air inlet or fuel leak, neither are a welcome thought.

 

[Doug4bass]

Until he gets a shutoff valve installed, how about a pair of channel locks (no teeth) to crimp the feed hose? Maybe just once?
P.s.... I have had fuel siphon with a lower tank. Not sure why....

 

[31seahorse]

Suncatcher,
In your posted picture there is a loose hose clamp that appears to be around the fuel inlet to your tank. Not a good thing! If you are changing hoses during this filter change be sure to double clamp all connections. If you are not changing hoses check all the clamps for rust or loose fit and check all hoses for cracks, brittle feel, or mushiness.

Hint for changing fuel filter......Wear old clothes, move things away that will absorb fuel you spill, invest in a spray bottle of Pure Ayre for diesel fuel. Pure Ayre will cover the smell of diesel fuel.

Read the information on how to "bleed" the fuel lines and the engine to the injectors so the engine will be happy to start when you finish your work.

 

[SG]

I would very much counsel against trying to squeeze a rated fuel line to shut it off. You likely damage it if you're not careful.

If the Tank IS NOT overfilled and has some air in it. Find the supply line between the tank and the initial fuel filter (hopefully you have two, a initial water and gross partical "Racor" and then a final one just before the engine. Then simply remove the hose fitting between the tank and the filter that is HIGHEST. The fuel will drain down into the tank. If if doesn't, blow it down into the tank. Then you can remove the hose at the tank. If you're hose is screwed-up, old, or whatever, replace it with a new marine diesel fuel rated supply hose, and petcock valve (if you need or want one).

You should have four fittings on your tank: i) fill hose to the deck fitting; ii) vent hose to the stern transom -- or some other dry place high above the waterline; iii) engine supply take-off hose; and, iv) an unused return fuel line back to the tank. Your engine doesn't use all the fuel that the engine fuel pump draws. It returns that excess fuel back to the tank.

Have you found all of there things?

 

[FastOlson]

Our tank came from EY with a metal ball valve right at the tank outlet. Seems like a good idea. If you ever have an emergency that involves the engine compartment, it's nice to (in our boat) just reach down below a settee top and shut that valve off. I usually shut it for filter changes also.
Hoses: if you see some cracking, just replace them all. The newer hose has improvements in the materials and given the increasing stew of chemicals in "diesel" fuel, that's a real good thing. In the greater scheme of things, USCG-approved hose is inexpensive.
As Stu points out, we all learned about diesels when we bought a boat with one.

 

[Dalliance]

I have shutoff valves at both the tank and the filter. Think the one at the tank is original and the PO added the one at the filter to make filter changes more convenient.
Ditto what's the others have said about replacing suspect fuel lines and learning about Diesel engines. I have the same Yanmar 2GM. It was all new to me, a bit intimidating at first, but basic maintenance is really pretty simple.

 

[Suncatcher]

•Yes the tank is higher than the engine so I worry about siphoning.
•I didn't notice the fuel intake clamp. I'll check and tighten that and double clamp it.
•I also didn't notice the 'vent' markings on the hose or the crack. I'll get the correct hose to replace it.
•and I'll check all the other engine hoses
•I'll also get a shutoff valve
•I'm thinking that the best way to get the hose off is by removing it at the secondary filter and holding it up so it drains back into the tank as suggested...while wearing old clothes...with plenty of rags handy!

Learning lots quickly!

Thanks for all input so quickly.

 

[dziedzicmj]

you may also get some fuel absorbent sheets. They work great in containing the spills.

 

[31seahorse]

+1 for the absorbent sheets. aka engine diapers I tried real diapers following someone's advice.......not as useful in my opinion.

 

[dziedzicmj]

the point is that the good absorbent pads absorb fuel, but don't absorb water (as opposed to any normal diapers that are designed to hold mostly water)

 

[Suncatcher]

Oil absorbent sheets good....human diapers bad...gottaca