Rating the factory 240Z fuel vent hoses

[Arne]

As part of the slow refresh of my red '71 240Z I knew I needed to replace all the fuel hoses, especially the big ones that go to the expansion tank in the right rear quarter panel. I'd read all the instructions for saving money by using generic fuel-rated hose and inserting sleeves in them to keep them from kinking and such.

But since I am more than a little reluctant to pollute my red car's originality, and also because I really didn't feel like messing with bending and inserting sleeves, I decided to bite the bullet and buy factory hoses. As a side benefit, I figured I could advise others on whether this was as good an idea as it seemed to me at the time. So now that it is done, here are the part numbers I used, and my comments. I got mine at club discount from my local dealer, but your dealer may not offer that. So I included prices from NissanParts.cc for comparison. (Prices current as of 1 May 2007.)

• 17239-E4601, $27.15. Smaller diameter hose, runs from expansion tank to top right side of the fuel tank. About 3 feet long. Has a preformed double bend at the tank end. This hose is apparently actually correct for '73 240Z, but works OK on '70-72 cars as well. (Correct '70-72 hose is NLA.) The double bend is not quite the same as the one that was on my car, but once pulled into place seemed to work well. Arne's advice - RECOMMENDED, but not absolutely required - The preformed bends do help for this hose. You might be able to get by with generic for this one, but the bend at the tank end might kink some on generic hose. Since this one is affordable, I'd do it.
  
• 17235-E4601, $53.20. Large diameter hose with several preformed bends, including a 180 degree bend at the tank end. About 4 feet long. Goes from the expansion tank through the floor to the back of the fuel tank on the right side. Correct for '70-73, fits perfectly. Arne's advice - HIGHLY RECOMMENDED - You need that 180 but would need to sleeve a generic hose to do it. The price of this hose is not that bad considering the three custom bends. Buy it.
  
• 17238-E4602, NLA as of 9/09. Large diameter horseshoe shaped hose, less than 2 feet long. Runs from expansion tank to fitting on filler neck. Correct for '70-73. Fits fine. Arne's advice - SOMEWHAT RECOMMENDED, not absolutely required - You can do this one fairly easily with generic, especially if you used a slightly longer hose than normal so that the bend was gentle. And now that it's NLA, you'll probably have to...
  
• 17236-E4601, $88.43. Medium diameter long hose. About 6, maybe 7 feet long. No bends at all. Runs from left side of tank up through the floor, across and into the bottom of the expansion tank. Correct for '70-73. Fits fine. Arne's advice - NOT RECOMMENDED - Unless you are a fetishist about original parts, use generic here. This is the most expensive hose from Nissan, but it has NO preformed bends. So there's no advantage to the factory hose on this one.
  

I also used 18" of 3/16" ID fuel hose (return line), 18" of 5/16" ID fuel hose (fuel supply line), and 4 feet of 1/4" ID fuel hose (evap tank to flow valve line) to do all the other hoses there while the tank was out. In addition, I got replacement grommets and hose sealing sleeves from Banzai. The hose sleeves could be replaced with heat shrink, but I felt the real thing wasn't all that expensive. My grommets were still soft, but the replacement hose from the top of the expansion tank to the metal line that goes to the flow valve on the left front inner fender (the 4 feet of 1/4" hose) was a smaller external diameter than stock. One of the grommets I got from Banzai was apparently intended to deal with this difference and worked great at that spot.

Anyway, the deed is done. For myself, I'm not sorry that for the red car I bought the long one from Nissan, but for my yellow car I would not have bought that expensive one.

I think it worked, the garage does not have that faint gas odor tonight, so I'm happy.

Edited August 5, 2011 by Arne

[madkaw]

Arne,

that vent system they came up with is unbelievable. It amazes me that they managed to use every size vent line from 1/4" to 3/4" hose. i am retrofitting a different tank to my car but still have to deal with the damn hoses. It's hard to find any hose over 3/8" for fuel venting with out special ordering. Napa wants 6.29$ a foot for there 3/4" and it's not formed.

So my point is, I guess, even though you paid alot, it's the easier route then trying to track down all these hoses. I have spent many, many hours trying to come up with ideas to limit the cost for my job , but the vent lines are expensive. That medium hose for 88$-----ouch

[240ZX]

Regarding aftermarket hose that will stand up to exposure to gasoline....try looking into TYGON tubing. The hose is clear and is available in many diameters and wall thicknesses. Just a thought!

[Arne]

Yeah, as I said, if I were doing it again, knowing what I know now, I probably wouldn't buy the $88 one. On the other hand, I believe that one is 5/8" ID (15mm actually). And fuel-rated 15mm hose goes for $6/foot or more. Get seven feet (to be certain you've got enough) and that's still over $40 right there. For the extra cost from Nissan, I did at least get cloth-braid.

[jackwarnock]

Hullo Arne

I posted a response to Carl Beck about this issue of Vent Hoses etc earlier. He made comment that we could do without the Vent hoses, so I have sought his advice on how to do it.

Meanwhile I appreciated your Post #1 above about the Vent Hoses you have used to replace yours. Thanks for the detail. However, I have been unable to find the Part #'s in my Australian Nissan Parts CD.

I have a 1973 JDM Fairlady 240Z. I am not sure if the same Vent Tank (called Reservoir Tank in my Nissan Workshop Manual) and hose combination is fitted to Australian delivered vehicles of 1973 vintage. However your concise description of the hoses matches mine exactly.

Today I spent some considerable time draining fuel tank and removing the old hoses. Most were fairly definitely original and very stiff - hence fuel leaks when fuel tank is filled. All the Forums/Posts I have read here confirm the problem I have had. Your Post was particularly helpful. Thanks.

Now the issue is - do I need to replace the Vent hoses or can I re-plumb without Vent Tank and Hoses?? I look forward to receiving advice from Carl Beck and others.

Alternatively, can you advise me of the supplier of your hoses, as I have my doubts that I will be able to find these here in Australia.

I will try Nissan Australia and other suppliers tomorrow (Monday), but seriously doubt that I can source the hoses in Australia.

Help or advice from others would be appreciated.

Regards, Jack

[jackwarnock]

Hullo again Arne

After re-reading your #1 Post I noticed the reference to grommets and sleeves from Banzai. I will need to replace these as well, so any help in directing me to suppliers would be appreciated.

Despite the cost, I would like to do the job properly to avoid fuel leaks and other problems. Unless the "elimination option" from Carl Beck will work, then I will need to source the hoses, grommets etc that you did.

Like someone else has said, Nissan managed to use every conceivable hose size made to construct this strange Vent system. What a crazy mess. Any way, hopefully when I fix it, it will be good for another 30+ years. That will do me then!!

Thanks again for your help.

Regards, Jack

[=Enigma=]

Jack, the reference to Banzai is to Banzai Motorworks here:

http://www.zzxdatsun.com/

[Art@NissanSport]

I just redid all my hoses.

I used a 3/4" multi-purpose hose from NAPA for this:

"17238-E4602, $19.81. Large diameter horseshoe shaped hose, less than 2 feet long. Runs from expansion tank to fitting on filler neck. Correct for '70-73. Fits fine. Arne's advice - SOMEWHAT RECOMMENDED, not absolutely required - You could do this one fairly easily with generic, especially if you used a slightly longer hose than normal so that the bend was gentle. But since it's so cheap..."

I had them cut me a 1' piece and it formed the exact shape (a natural curve) needed when cut to that size. Total cost: under $7.00. Would probably go one size larger next time. The mult-purpose hose comes in many sizes larger then 5/8".

[hls30.com]

Regarding aftermarket hose that will stand up to exposure to gasoline....try looking into TYGON tubing. The hose is clear and is available in many diameters and wall thicknesses. Just a thought!

Tygon is excellent stuff, I believe using it would give a permanent repair.

It is what I will be using for low pressure fuel lines.

Will

[JimmyZ]

Amazon hose here in Orlando has the exact diameters needed. (fractional inch stock not metric but it's close enough) Total for all hoses thru them was $60.00. If U like I could get some for you.

Jim

[a7dz]

Tygon is excellent stuff, I believe using it would give a permanent repair.

It is what I will be using for low pressure fuel lines.

Will

I would be careful using Tygon tubing. When exposed to fuel and oils over extended time periods it expands, doubles or triples its original size, completely loosing its shape gets sticky where exposed. I have not seen it burst but, have seen it collapse and seal it self off. I would still use a more rigid hose that is rated for gas, fuel and oils. I do not believe the cost savings out weigh the risk of hidden fuel problems later.

[sblake01]

I buy most of my hose from ACE Hardware. Since I work there, I get it for cost+10%. The 5/16" 200psi fuel line used in many parts of the the 280Z efi costs me .55/ft. I can get any size even the ones we don't normally stock from one of our distributors for much less than the normal over-the-counter price. With that in mind, I generally choose practicality over originality.