Fuel Tank Vent Lines

[sdyck]

 Considering eliminating the vent tank. According to a search there are supposed to be instructions at this link;
http://www.classiczc...light=fuel vent
 

But the link doesn't work. Does anyone have a better link?

 

Thanks

[mlc240z]

Just did this due to the issue of a full tank and a left turn would release gas fumes into the interior. While I had the tank down, had it boiled out and sealed at a radiator shop that also did the Renuzit (?) tank treatment. When the guy looked at the tank, he said it didn't need the full treatment for around $300+ (which I would gladly have paid) but instead boiled it out, coated the inside and painted the outside. Still paid about $200 but should be good for another 20+ years. Also replaced all vent lines and the filler tube (MSA and aftermarket generic fuel lines). Still able to get about 2 of the lines from MSA but got creative with the bends needed for the unavailables. Used a spring inserted inside generic fuel line for the big bend to prevent collapse of the line. Also read you can use the PEX/plumbing brass 90deg elbow to make the sharp corner. Result is a full tank, left turn and no gas smell inside the cabin. Exhaust smell would def benefit from a redo and seal of all tail/hatch gaskets. I'd already done that part in addition to adding an extension to the exhaust and seal of the antenna drain tube grommet.

You can get away reasonably cheap except for the tank boilout/treatment. But I look at it this way. I'll prob never have to d*** with this again in my lifetime.

sorry for the long post but go for it.

[sdyck]

Thanks Bart, will probably go the same route. Considering just eliminating the vent tank and lines and capping things off. Always worried this will lead to other issues, so will probably do the whole thing.

Steve

[FastWoman]

Use Goodyear E-Z coils for the bends:

 

http://www.veyance.com/productsDetail.aspx?id=17254

 

You can get larger size fuel hoses from a tractor supply house.  You can also buy some really nice marine-grade hose from a marine supply store.  If it's USCG marine-rated, then it's fuel resistant.  DON'T use heater hose!

 

I think your decision to keep the little tank is probably a good one.  I think it courts problems to buck the design.

[siteunseen]

I bought all my hose at an O'Reilly's Auto Parts store.  They had all the way up to 5/8" on hand.  Hoses and clamps were around $60, quart of Red Kote tank liner was $30.  I have hundreds of PEX fittings, so $100 and a week of time.  If I can find some of the pics.

Don't forget a Fram G2, $3 bucks, coming out of the tank's supply side.  That picture isn't my 240s G2, thats a 280 with the G3.

Nissan still has the fuel sending unit, $50.  The wires going to it are what they call "nail head" connections and they are a PAIN.  When you get them on slather them up with liquid electric tape.

 

Picture: I used a 1/2" pex 90 degree for the small vent line above the sending unit.

You'll need two 3/4" pex 90s for the 180 turn on the top of the tank, it's the 5/8" hose connection.  I'll find a picture of that somewhere, I know it's on my computer!

That box has the Nissan part number for the sending unit.  You'll also need an O ring, p/n 17342-18000

Gotta go, more when I get time.

 

Cliff

[mlc240z]

Fastwoman, definitely looked at the E-Z coils. I felt since they're only vent lines (no liquid to worry about flow restriction) and the bend was so extreme, I'd rather worry about the inside diameter collapse. Plus the stainless springs were cheaper.  

[FastWoman]

Not cheaper than my EZ Coil!  The auto parts guy had a couple of samples, didn't figure they could sell any, and said, "Here, try this doodad.  It might work."  And it worked great.  Seriously, I have no idea what they cost.  They look a bit pricey.

[sdyck]

Cool, love the pics. Took a look for the EZ coil. Canadian tire sells them for $7.00 a pop up here might give them a try

FastWoman, did you use the EZ coil so the 180 degree bends? and no issues?

[siteunseen]

Her 280 doesn't have all that mess, fuel injected. 

 

Finally found a good thread with pictures for reference, http://www.classiczcars.com/topic/17542-treating-insideoutside-of-gas-tank-with-por15-products-and-removing-evaporation-tank/

He's deleting the tank though but still has some useful info.

 

Here's another picture that'll make you cringe.

[FastWoman]

Sdyck, I seem to recall the EZ coil instructions saying you can bend 90 deg max, but I think I could get nearly (not quite) 180 out of mine.  No issues that I know of. 

[Marty Rogan]

Use Goodyear E-Z coils for the bends:

 

http://www.veyance.com/productsDetail.aspx?id=17254

 

You can get larger size fuel hoses from a tractor supply house.  You can also buy some really nice marine-grade hose from a marine supply store.  If it's USCG marine-rated, then it's fuel resistant.  DON'T use heater hose!

 

I think your decision to keep the little tank is probably a good one.  I think it courts problems to buck the design.

I removed the vent tank with no problems whatsoever.  It is a U.S. Emissions device.  Non U.S. vehicles leave them out, per Nissan's design.  I even used a Nissan hose from a non-U.S. spec vehicle that deleted the tank.  That was many years ago and I don't have the P/N any longer.  It may be in the parts manual though.

[Carl Beck]

I eliminated all the vapor recovery lines etc - about 20 years ago. Never caused any issues/problems.{as long as you keep that top tank vent open - i.e. making that 180 without kinking the hose}.  Many of the 69 production 240Z's didn't even have it to begin with. Canada didn't require it, nor did the US in 1970. California did... and the rest of the US followed, so it became standard on all North American models.

 

So it isn't so much a design element - as a last minute add on for California in 1970. 

 

FWIW,

Carl B.