OK Why the extra fuel line

[TigerShark_Rookie]

1994 Tigershark Barracuda

I checked the service manual and the net and I still don't know what the third line from the fuel tank is supposed to do.

According to the manual
The outermost hose is the supply line from fuel tank to the fuel pump on the carb
The innermost hose is the return line from the fuel pump on the carb to the fuel tank.

The middle hose (which is T'ed) is the question.
One line from the T has a check valve and then a fuel filter at the end
This I assume is the air inlet to the fuel tank (thus the check valve)

The second line from the T (is a mile long) and also has a check valve only allowing flow back to the tank

What is this for ?
Where does it attach to ?

Thanks
Dennis

[John Kubiak]

Re: OK Why the extra fuel line

It's the pressurization line for the Torpedo Tubes!!!

Actually, it's the fuel tank VENT; one side of tee goes to vacuum relief valve (near handlebars) the other goes to pressure relief valve Below bumper rails and above the waterline on the lower hull.

[TigerShark_Rookie]

Re: OK Why the extra fuel line

It's the pressurization line for the Torpedo Tubes!!!

Actually, it's the fuel tank VENT; one side of tee goes to vacuum relief valve (near handlebars) the other goes to pressure relief valve Below bumper rails and above the waterline on the lower hull.

OK I understand the tank vent near the handlebars (as fuel leaves the tank it must be replaced by air - thus the one way valve, air in only, on the vent line)

What I don't understand is where the other line attaches or goes.
Pressure relief would imply to me that if the tank suddenly builds pressure it is released thru this line (also containing a one way valve - out only) but where is it dumped.

The thought of having gas vapor or liquid dumped in the bottom of my ski does not sound appealing at all...

Wouldn't it be smarter to just remove the one way valve on the first line and let it act as a vent - Thus removing the T and the second line altogether ?

Thoughs
Dennis

[John Kubiak]

Re: OK Why the extra fuel line

The pressure relief valve is an overboard vent.....There are times during operation that the fuel system is under pressure, and other times that the fuel system pulls a vacuum. Most service manuals clearly illustrate this, and both check valve locations...what manual are you using???


No it is not "smarter" to alter or modify the fuel venting system to your own configuration.

[TigerShark_Rookie]

Re: OK Why the extra fuel line

The pressure relief valve is an overboard vent.....There are times during operation that the fuel system is under pressure, and other times that the fuel system pulls a vacuum. Most service manuals clearly illustrate this, and both check valve locations...what manual are you using???

No it is not "smarter" to alter or modify the fuel venting system to your own configuration.

OK - "Pressure relief valve is an overboard vent" - That make much more sense.
I'll scrap the idea of modifing the fuel venting system...

Now where in the <bad word> does it attach to the hull.
I can not find a nipple or hull grommet anywhere...

The service manual I'm using is a brand new 1994 Tigershark watercraft Service Manual produced by ARCTCO.
(Should be the horses mouth right ?)

The only reference to the fuel tank vent check valves in the entire book is a small blurb on the bottom of page 66...

While it states that the fuel tank is vented with check valves it also states in bold print the following two notes...

NOTE:The Check Valve in the vent line near the steering post must allow air to flow out of the tank, but not into the tank

NOTE: The check valve in the vent line secured to the hull must allow air to flow into the tank, but not out of the tank.

It is my belief that these two notes are completly - Backwards ...

I really hope that Arctic Cat doesn't dump fuel vapors or gas in the front hull by the steering post
and I also hope that they don't allow water to be sucked into the tank from an overboard vent...

Help anyone
Dennis

[John Kubiak]

Re: OK Why the extra fuel line

You get what you pay for...Ever wonder why Arctic Cat is out of the watercraft business, and has been for almost 7 years? Hmmmmm?

[dank]

Re: OK Why the extra fuel line

Correct,

The one that goes overboard should not let air or water in. The one under the handelbars should let air in only and not out?

What is so hard about that? The filters are there to keep the lines clear.

That is the same as most every ski on the water and most severice manuals have erros in them. I am not sure why that put them out of buissness.

[TigerShark_Rookie]

Re: OK Why the extra fuel line

Correct,

The one that goes overboard should not let air or water in. The one under the handelbars should let air in only and not out?

What is so hard about that? The filters are there to keep the lines clear.

That is the same as most every ski on the water and most severice manuals have erros in them. I am not sure why that put them out of buissness.

Nothing...

That's why this rookie said I believe the manual has an error...

My only remaining question (about gas line vents anyway) is where does the pressure relief valve hook to the hull or overboard outlet.

The hose is long so I must assume that it is near the back.
Does it attach to the Exhaust or something like that ?
Is it on the right or left side of the craft ?

Can someone with a TigerShark take a photo or draw me a detailed picture of where it exits the craft.
I must be blind...

Again this is a 1994 Tigershark Barracuda...

Thanks
Dennis

[dank]

Re: OK Why the extra fuel line

On the right side next to the bilge outlet. There should be a 90deg rubber outlet pushed threw a hole in the hull.

[TigerShark_Rookie]

Re: OK Why the extra fuel line

On the right side next to the bilge outlet.
There should be a 90deg rubber outlet pushed threw a hole in the hull.

Thanks - I'm still looking and thus far all I see is my "Torpedo Tubes" (sorry from different post).

If someone can take a picture of this pressure relief outlet I'd pay them for it
(Its got to be from a 94 - 95 Tigershark Barracuda)...

I can take pics of any part of my shark But I don't see anything next to the bilge outlet on the hull...

Still puzzled... :emoticond
Dennis

[dank]

Re: OK Why the extra fuel line

Here is the picture. I think it is under the handlebars thre a rubber grommet.

[dank]

Re: OK Why the extra fuel line

OK second try

[TigerShark_Rookie]

Re: OK Why the extra fuel line

Here is the picture. I think it is under the handlebars there is a rubber grommet.

Ding Ding Ding - Yea Haw - We have a winner :emoticont (I think)...

Wow I would have never guess that the pressure relief line for the gas tank would be vented out under the handlebars...

I saw that rubber grommet and assumed (yea Bad I know) that it was for an optional tack or speedo or something along those lines...

I enclosed a couple picts just to make sure we are all on the same page...

I want to say thanks to all those who helped out (especially "dank")
Super Site with Top Notch Tech Help... ("Torpedo Tubes" and all)

Thanks
Dennis

[dank]

Re: OK Why the extra fuel line

Glad to here you got it. I was on vacation the last week and just got back.