Biodiesel fuel line replacement on '82 720 SD22

SD diesels were widely available in the US in the 1981-86 Datsun/Nissan 720 pickups, and in Canada through '87 in the D21 pickup.

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asavage
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Biodiesel fuel line replacement on '82 720 SD22

#1

Post by asavage » 13 years ago

[I originally wrote this post at BiodieselNow.com's FAQ forum.]

More than a year ago, I bought, repaired, drove, then sold an '82 Datsun 720 diesel pickup. I drove it a little more than 1000 miles on B100, and the woman (a local) who bought it, did so expressly to run B100, which she did for the next year.

When I sold it to her, I warned her that at some point in the future, the fuel lines would have to be upgraded. Almost exactly a year later, one pressure line began weeping enough to drip, and that's when she called me and I ordered the McMaster-Carr viton tubing, in three diameters for this rig.

I took out the fuel tank,
Image
a task made easier due to the OEM fitment of a drain plug. While the tank was down, I replaced the fuel suction line and return line as described below; I did not replace the vent line, the filler neck hose, or the filler neck vent line (runs up the side of the filler tube).

On the advice of a couple of people here, I ordered three diameters of viton tubing from McMaster-Carr and when it arrived I was shocked at how thin the wall is on this stuff.
Image

A worm-drive hose clamp will not only not effectively clamp it, but would likely tear it. I called Greaseworks in Oregon, and asked Justin what he uses on their conversions, he gave me a couple of ideas and added that the viton tubing isn't very abrasion resistant either, and he suggested sheathing it inside other hose in places where abrasion could occur.

So I scoured various sources for appropriate clamps, and thought I'd found something that would work well: plastic ratcheting clamps.
ImageImage
When I tried them, some of the pressure lines would still leak, so I double-clamped them, but I also found that they aren't really reuseable after all. One use, and the next time they won't ratchet and hold anymore. Bummer.

Adjustable band clamps, such as NAPA/Balkamp's 705-1226
Image
aren't readily available in a small enough clamp range to accomodate the OD of the viton tubing.

What I ended up doing was using a 3/4" long piece of Gates 3/8" ID fuel line, and putting it over the viton line where it fits over the hose barb. A sheath or sleeve. Then I used the Balkamp band clamp to clamp on that. For the 8mm fittings (the majority), it works very well. Looks a bit odd. I have about seven connections done like that, and they don't leak a bit. They can be removed and reinstalled without damage to the tubing.

I also sheathed several of the long runs that wiggle around with the same 3/8" fuel line, but slit down the side so it was easy to slip the viton tubing inside. I was also able to re-use the OEM SS braided hose covers near the IP. The sheathing also helps to prevent the viton tubing from kinking, which it will do if you look at it cross-eyed; the thin wall again.
Image Image Image Image Image

Along the way, the primary filter (a filter much like the old MB "prefilter") got inadvertantly switched to one physically identical, but for a gasser: it had a paper element. When I was still using that (wrong) primary filter, I was generating a lot of vacuum on all the suction lines that isn't normal for the system -- at one point I measured 11" ! I suspect even the OEM lines would have been compromised in that situation, but it was very clear that the viton lines were flattening out. Inserting 3/16" or 1/4" x 12" long compression springs (loose coil wind)
Image
inside the suction sections of viton tubing moved the problem from the lines back to the filter. I do not know if there would be a problem with the viton lines collapsing in a normal vacuum situation, but the springs were cheap insurance (about $3.50 for 12"). And, like the outer 3/8" sheathing, the springs help prevent hose kinking as well.

The McMaster-Carr viton tubing is a PITA to work with. Lubricants won't "stick" to it, so even pushing it on hose barbs is not easy. It's thin wall and requires care and a special clamping technique. But it's the only tubing that I know will work in the long-term, because it's been done before, and that's why I used it. I hope to find something easier to work with for the next one I do.

I hope this helps someone avoid the pitfalls I found.
Last edited by asavage 12 years ago, edited 2 times in total.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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#2

Post by diesel-man » 13 years ago

Al:
Are you running your Maxi on biodiesel? I take it that you don't have this truck anymore. Did you make small batches of Bio or did/do you have a good size operation?
I saw on DirectTV on the Dirty Jobs w/Mike? Rowe that a segment about a month ago, had a guy that took Rowe to some restaurants to pick up WVO, (in a Datsun diesel pickup) went back to this guys garage to make Biodiesel. I seem to remember he made over a 100 gallons at a time and it was taking up his whole garage!

I read another post about how "they" shut the car off on Bio and came back out later :( .......

Give us a snapshot of the "joys" of WVO & Bio. How much would one have to make to be worthwhile? I searched it out on Google and there are a couple ways (chemicals) to come around to the same end (slightly different process) Cost?

I'm all for saving money, it only takes a small "amount" of Scotch in the mix to make a person this way. Scotch in the geneology is like yeast in bread...it ain't gotta be the main ingredient...

I am doing all I can for OPEC already, I bought an outdoor wood boiler to heat the house. I used to use about 600 gallons of heating oil when keeping the thermostat @ 68 in the evening and I used to turn the heat off at about 11:30 just before going to bed. We would get under two "wooly" blankets and sometimes it was as low as 50 in the morning. Since the wife always got up first (she's the brewmaster) to make the coffee, this routine did not go over so well, but she is a little Scotch at times (guilty by associtation) just like I'm a little bit Italian now.

Then two Winters ago I went back to using the wood stove in the living room to save oil. When it is less than 10 degrees outside and the wind is going 30+ mph and the heater is running every ten minutes? you don't even have to be Scotch to want to do something! :shock:

Anyhow now with this outdoor boiler we keep the house 75, 76 or whatever feels good that night. The wife just loves it, one day I'll have to teach her how to use it? :wink: Although, if she tries to teach me about the washing machine......... That is a contraption I don't think is possible for me to understand 8)

I got this story about "The Diary of a Snow Shoveler" it is Off Topic, has a few bad words in it, but I'm most sure you will ROFLYAO and bring tears to your eyes laughing. You'll have to ask for it... not going to volunteer it.

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#3

Post by asavage » 13 years ago

So much has been written and said about "biodiesel" . . . and so much of it is bullshit . . .

I'll try to keep this short, but I encourage you to try to find two hours and do your own research (I can recommend biodieselnow.com). I am not quite an expert, but I am damned close at this point, having been in the game for about 2.5 years.

"Biodiesel" has a specific definition: it's transesterified oil. The oil (feedstock) can be new or used, and vegetable or animal sourced.

What "biodiesel" (BD) is NOT (not!) is just oil, or oil mixed with kerosene, or oil mixed with Sta-bil, or oil mixed with . . . you get the idea. BD is not oil mixed with anything. If the feedstock hasn't been transesterified, it's not BD, period. If you don't believe me, you can argue with the National Biodiesel Board and the Feds, who made the definition.

In order to be sold as a fuel or as an additive, legally it should have to pass the BD ASTM specification D-6751. That's right, there's a series of defined tests (just as there are for petrodiesel (PD)), and if a test batch of BD won't pass the tests, it's not BD, it's homebrew or worse.

People are putting all kinds of crap into diesel engines these days, many of whom are doing it because they heard some things about "biodiesel" and thought they could save a buck, or save the whales, or boost local economy, or just hang out with other folks of like mind . . . and a whole lot of otherwise useful diesel engines are being scrapped as a consequence. That's my opinion, and I've seen enough of this to be convinced.

[ . . . pause to calm down . . . ]

Alternative diesel fuels these days fall broadly into three categories: BD (that which passes ASTM D-6751, and BD that doesn't quite); Straight Vegetable Oil (SVO) and Waste Vegetable Oil (WVO, which strangely enough includes non-vegetable oils, go figure) that are filtered somewhat; and gawd-awful SVO/WVO/bathtub-homebrew mixtures.

Each category has it proponents, advantages, and drawbacks. It's beyond the scope of one post by myself to do a decent job of even outlining all of those. Suffice to say that I am a very big booster of BD. BD (which is NOT VO/WVO) is a fuel which burns cleaner than PD (much lower HC, CO, particulate emissions (PM), and sometimes -- but not always -- slightly higher NOx in engines that have not had their IP timing backed off 1-2°). BD contains no sulphur, so no acid rain. BD has hugely enhanced lubricity over PD. BD smells a lot better (when burned) than PD -- as Philip says, it smells a lot like house paint in unburned state: linseed oil-like. BD is non-toxic and is not classified as a hazardous material (though the chemicals used in its productions definitely ARE) and you can just put a bunch on the ground and it won't do a thing. It degrades relatively quickly when exposed to air & sunshine (compared to PD). BD has a much higher flash point than PD, so it's less of a hazard to handle & transport.

BD can be produced, in quantity, domestically. If you research much, you'll find people who say it can't put a dent in domestic PD requirements, but they're ignoring algae (yes, algae) and Thermal Depolymerization (TDP), and you can Google those too if you're interested -- my point is that they're wrong, but lot's of wrong things get propagated in the internet.

BD is not fuel cells, but it can be put into the existing fuel distribution system NOW, whereas the "hydrogen economy" (which I believe to be a pipe dream, supported and propped in much the same way that Micro$oft props up Apple so they can point to Apple and say, "Look, we do too have competition!") is pie-in-the-sky BS that is years -- many years -- away from any kind of mass use.

I'm biased: I've spent a great deal of time educating myself on BD, and I help maintain our local BD distribution point -- for fuel brought in from Seattle, and whose feedstock is soy oil from the Midwest. Stoopid, but true. The Seattle area has, I've read, the highest concentration of BD users in the US. I'm hours away from Seattle out in the boonies, but I can get our three 260 gal totes filled every month by a tanker that comes by.

Today, by far, most US BD is made from soy feedstock. Soy is not the best feedstock for BD production, it does not have as high a yield per acre as several other plants, and the fuel produced is a compromise of qualities -- there are better alternatives. However, raising soybeans is well understood in the US, and the soybean industry has a mature infrastructure that is partially subsidized by our tax dollars, so soy oil it is . . . for the time being.

Um, where was I?

The Datsun diesel 720s: I owned one '82 1.5 yrs ago that I bought ($400, from Mercer Island, 86k original miles) with a trashed transmission (read my other posts on this trans, it's the same guts as in the Maximas, and indeed as several other Nissan products for many years, and has several weak points), and I did a decent job of fixing it up, then sold it to a local ($2000). It has run B100 exclusively since I purchased it (1000 miles by me, 14k miles by the new owner), and if you've read the above, you know about at least a couple issues with B100 use and old vehicles.

I bought another '82 720 diesel four months ago for a friend ($160, Bellingham, non-runner) with a bunch of problems, mainly a stalled Injection Controller Motor and a lot of cut/bypassed fuel lines, and huge rust issues, still looking for a donor gas truck to do a drivetrain transplant), and after doing minimal work on it and getting it running well enough to vet the engine, I compiled a list of items it needs, and sold it to a coworker ($400), who is running it on B100 and also working down the list. It's a real timesink, but he wanted a small diesel PU, and there just aren't a lot around (for a pretty decent list I put together two years ago, see this post of mine and scroll down about three screens worth to see the list.). It's not much of a PU, but it does what he wants.

I try to get local folks to see the long-term wisdom of BD use now.

BD is not cheap, if you don't own the feedstock. We are selling it for $3.49/gal right now. As BD goes, that's pretty cheap, and it's not (right now) competive price-wise with PD. It was actually cheaper than PD right after Katrina, around here anyway. But I don't proselytize BD on its economic benefits anyway.

If you have your own feedstock (or can procure it, as in fryer grease, donut shop oil, etc.), if you don't mind working with hazardous materials (lye, methanol, which combine to form methoxide, and it's not nice stuff to have in your basement unless you really, really mind your Ps & Qs), and have the space and patience (and the ability to compost or otherwise safely dispose of the glycerin -- about 10-15% of the raw feedstock is going to convert to the base stock of bar soap!), then you can certainly save a pile of money by producing your own biodiesel. Lots of people are successfully doing it. There are excellent kit plans (Girl Mark has the best by far), kits, and entire fuel processors available for BD production -- and not a few rip-offs too, this being a fad kind of thing right now. There are all kinds of downsides too, but again, if you have the feedstock or can get it for a reasonable effort, and if you use enough fuel to make it worthwhile (say, fleet operation or home heating) then producing your own BD can make sense.

I have a whole list of things that I don't like about burning SVO/WVO and the crap that's being sold by one outfit that's supposed to "convert" feedstock to safe fuel without transesterification, but I'll spare you and admonish you to read a lot before going down the SVO/WVO and additives path -- beware, Luke, the Dark Side of the Force, etc etc. Burn glycerine and you get acrolein out the tailpipe, and injector coking, ring land coking, IP input shafts breaking, lube oil contamination . . . now there, I said I wasn't going to get into that list . . . do your own research, but I'm exciteable about the whole "put the fryer oil into your tank and drive" crap. Even Elsbett and Greasel don't convince me, they haven't got all the bases covered, but they're still selling a lot of hardware to hopefuls -- for the wrong reasons, IMO.

[ . . . more deep breaths . . . ]

As I've written somewhere else on this site, and on other sites, the Bosch (Diesel-Kiki, under Bosch license) VE IPs are weak: they leak. They leak in normal usage. They leak a lot faster when using "low-sulphur" (today's PD in the US) and "ultra-low-sulphur" (ULSD, we all get it nationwide in Sep-06 by Fed mandate). There is a thread on this site (and many others) on this topic.

I have run some B100 in my LD28, and now my IP leaks, presumably at the front seal. In my opinion, it would have leaked anyway but the B100 definitely pushed it over the edge fast. I still run B100 in it (it doesn't leak much, and I don't drive it 2k/year these days). I have the last (AFAIK) two NOS 1982 injection pumps available in the US, in storage -- I bought them for a song ($850 for the pair) two years back from a liquidator. My idea was to swap one in for mine -- this was before mine was leaking, mind you.

Now, if my leak is the front seal, I'll probably just replace the seal. I bought the Bosch Book on distributor-type IPs (ie the VE series) and have read it cover-to-cover twice in the last month, and now know more about it than any sane person should -- it's not a rebuilder's book, it's all theory, and it's good, if you can get by the weird translated German. Recommended if you're interested in these critters, and it's only $23. Anyway, now that I understand the nine major systems in the VE IP, changing the seal is no big deal. And if I screw it up, I still have three other IPs with which to work.

[ . . . ]

Yeah, if you run SVO/WVO (or really bad BD that hasn't been washed well, or is not fully reacted), you will have problems getting the engine started -- and fuel system and overall engine life is reduced too, but most people only focus on the starting issue.

To my way of thinking, home BD production for home heating make more sense than for use as a vehicle fuel. But read up, there are drawbacks, too.

It's gotten late enough, and I have two other projects to research tonight, so I'll stop now. I'm not even going to proof this post, I'll edit it later.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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ecomike
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#4

Post by ecomike » 13 years ago

If I ever try biodiesel or WVO I will change the fuel lines, but I probably will use industrial low pressure (less than 250 psi) paint line hose (like Binks Paint Eq. Co. has) which has a solid polyethylene inner tube, is reinforced, and has an oil and abrasion resistant elastomer outer cover.

It holds up for years even when flushed repeatedly everyday with MEK, Toluene, xylene and other highly aggressive industrial paint solvents. It should be a lot less expensive that Teflon, Kynar, or Viton, and it will handle tight bends and vacuum conditions with out collapsing.

I use to sell it the 3/8" ID Binks hose for about a $1.00 a foot.
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.

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#5

Post by asavage » 13 years ago

OK . . . where do we buy it? And is it available in metric diameters, or at least 5/16" for 8mm?
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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ecomike
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#6

Post by ecomike » 13 years ago

Since I live in Houston, Texas I would pick it up at one of the many local paint equipment distributors here or the generic equivalent hose at a large hose specialty hose company like Willco Supply.

We could probably find an online hose supplier these days.

I just did a quick search and found 3/8" ID (11/16"OD) and 1/4" ID by 1/2" paint hose at http://www.spraygundepot.com/scripts/de ... 0503130053
I hope I did the link right?
They are asking $1.65 ft for the 3/8" ID hose.

The paint hose is probably only available in those two sizes, but

AL,

Before I look any further (and I will) for an online source of the generic equivalent hose in odd hose sizes to recommend for all of us, what prefered ID hoses do we want and what are the OD limits for each?


In Seattle you might try Finishing consultants, 800-514-0095, at:
http://www.finishingconsultants.com/
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.

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ecomike
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#7

Post by ecomike » 13 years ago

I found a generic one online, still 1/4" and 3/8" ID's, but it uses Nylon which is even better than PolyEthylene.

http://www.amazonhose.com/Paint_Solvent_Hose.html

Interesting list of products these guys have. Never heard of them but looks interesting! http://www.amazonhose.com/products.asp
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.

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#8

Post by asavage » 13 years ago

ecomike wrote:what prefered ID hoses do we want and what are the OD limits for each?
8mm is the majority. 10mm for some, and I think 3mm for return lines. I do not recall where the 10mm is used, but I used some.

The line you describe does not sound very flexible, and diesels move around a lot. The viton line I used above (in the first post in this thread) was too floppy.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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ecomike
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#9

Post by ecomike » 13 years ago

Great I will see what I can find. Isn't there one size that has an OD limit as well because of some kind of clearance problem?

Because it is fiber reinforced with an EPDM (in some cases) outer cover it is fairly flexible and can handle pretty tight radiuses.

It would require good stainless steel worm gear clamps. The standard paint industry fitting is a hose barb assy that threads into the nylon tube and then a threaded outer fitting goes over the cover and threads onto the outer part of the inner hose barb. As they are threaded together they squeeze down on a brass ferrule that forces the hose tight against the inner hose barb. They are typically rated for pressures of at least 250 PSI.

They are suprisingly flexible, with out collapsing on the inside. The 1/4" ID hose can probably handle a 360 degree, 1.5 to 2" radius turn.
The neat part is you get the chemical resistance of nylon on the inside, plus the flexibility and abrasion resistance of an elastomer (like EPDM) on the outside, in this composite hose.

Here is an interesting pub on Viton and automotive applications I just ran across by Dupont-Dow.com that has caught my eye.

http://biofuels.coop/archive/viton.pdf
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.

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asavage
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#10

Post by asavage » 13 years ago

2" radius is fine. I was envisioning something that couldn't make the many bends.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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83_maxima
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#11

Post by 83_maxima » 13 years ago

What about the clear medical-grade tubing the fellow used to convert his Datsun diesel on that episode of "Dirty Jobs" (if anyone saw that)? Looked similar to silicone, but I am not certain of the material.

I have not heard it mentioned by anyone here, but the fellow seemed to know what he was doing when it came to biodiesel.

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asavage
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#12

Post by asavage » 13 years ago

If someone is running WVO/SVO, the materials compatibility is much wider. I don't know about that fellow's project; perhaps he wasn't running biodiesel, but WVO instead.

As noted in the first post of this thread, tubing collapsing due to vacuum was initially a problem. Too-soft tubing is no good, unless an anti-collapse spring is used.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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83_maxima
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#13

Post by 83_maxima » 13 years ago

I'll see if I can't find out more about it.

I am sure I am not the only one that saw the episode, but he was making *biodiesel* from WVO ad running it in a datusn diesel pickup, most likely an SD22 - 1982.

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asavage
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#14

Post by asavage » 13 years ago

Much of the "medical grade" stuff I've worked with is useless around aromatic hydrocarbons. So color me sceptical -- until more info is found.

Viton works, it's proven.

from http://www.me.iastate.edu/biodiesel/Pag ... sel22.html
Material Compatibility

Biodiesel interacts differently with materials than diesel fuel. Some metals have a catalytic effect on the biodiesel oxidation process. Contact with these materials should be avoided, particularly for biodiesel in long-term storage. Copper and copper-containing alloys such as brass and bronze should be avoided. Lead, tin, and zinc are also cited as having some incompatibility with biodiesel [Tyson, see below]. Aluminum, steel, and stainless steel are acceptable tank materials and stainless steel and black iron are commonly used for piping. Galvanized and copper pipe should not be used for biodiesel or diesel fuel. The table below shows the effect of biodiesel on elastomers and polymeric materials.
Material  	BXX 	Effect compared to diesel fuel
------------------------------------------------------------
Teflon 	 	B100 	Little change
Nylon 6/6  	B100 	Little change
Nitrile 	B100 	Hardness reduced 20%, swell increased 18%
Viton A401-C 	B100 	Little change
Viton GFLT 	B100 	Little change
Fluorosilicon 	B100 	Little change in hardness, swell increased 7%
Polyurethane 	B100 	Little change in hardness, swell increased 6%
Polypropylene 	B100 	Hardness reduced 10%, swell increased 8-15%
Polyvinyl 	B100 	Much worse
  	 	B50 	Worse
 	  	B40 	Worse
 	  	B30 	Worse
 	  	B20 	Comparable
 	  	B10 	Comparable
Tygon 	B100 	Worse
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

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ecomike
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Location: Houston Tx

#15

Post by ecomike » 13 years ago

Well thats it then, that chart confirms that nylon, specifically nylon 6/6, but still nylon, is unaffected by biodiesel even B100. Therefore the nylon tube lined, industrial paint hose should be an excellant lower cost choice for fuel hose.

I noticed on that Dupont-Dow site I posted in last nights post that most (if not all) new cars have fuel hoses made with a thin viton liner on the inside of the fuel hoses. Most of them were pre-fitted, molded fuel hoses which does not help us, but it makes me wonder if there is not an unfitted, universal fuel hose by the foot available at the typical auto parts stores now that has a viton liner inside?

I also noticed that they were using polyesters and hydrogenated nitrile rubber in some of the outer cover materials over the viton core. Since the new car viton core hoses are not solid viton it is probably a lot less expensive and it was reinforced hose like the paint hoses I was talking about earlier. :D
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.

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