if I replaced my plastic fuel lines

I might be interested in replacing
the plastic fuel lines on my jetta 1.6NA 1991.
I would like to go with clear lines........
So can see the fuel
What kind of lines should I get????
Would like to run Bio through it too......
polyproplene,tygon????????
SAEJ30R9 compatible.

just read your other thread and i think you might be on the right path by wanting to replace the fuel hoses, unless you live in the north you should not have much troubble with the metal fuel lines. though these hoses are not clear i have had good experiences with plastic tubing for air brakes and the fuel hose that lowes stocks. the lowes stuff is just labled fuel hose, but seems to do very well for diesel applications. the air brake hose should be available at any hose shop like the ones that fabricate custom hydraulic assemblies, or maybe a shop that services semi-tractors. it works well to replace the tubing between the pump and filter base, and once you are able to get it on the barbs on the banjo fittings removal is impossibel without cutting it off. it helps to dip the end in boiling water for instalation. good part: probably impervious to any liquid known to man, abrasion resistant, will not leak at the fittings; bad part: available probably only in black. anyway, if there is a hose with a chewed up end go ahead and repalce it.

i can't really advise the use of the small worm gear hose clamps (any of them for hoses less than 3/4" seem to be single use, if that) insted try the solid band single size clamps, nearly every auuto store has them, but you have to ask since they are typically sold per piece without packaging.

another source of air leaks that are always overlooked is the copper washers in the banjo fitting assembly. if you have a propane torch handy you don't need to buy new ones every time you remove and replace the banjo bolts, just aneal the copper washers by heating them untill they glow red and let them air cool, then they will crush like new ones and form an airtight seal. sometimes if they are really out of wack but thick i'll lap them with coarse sandpaper on a flat surface, but rest assured that new ones are cheap but never manage to make it onto the shoping list (it is always something).

another place prone to cause an air leak is the bleed screw on the top of the filter base. small o-rings work ok in a pich if you don't tighten the screw enough to push the o-ring out, but a better solution is a small teflon or copper washer. i guess that one is a situation to see what you can dig up.

anyway, if replacing the hoses does not work i guess the best thing to do is obtain a hand powered diagnostic vaccume pump and plug one end of the fuel line and pull a vaccume from the other end and see if it will hold, if not chase down the hissing sound.

Yeah, thanks on the input there Zag...
Do you think while I am replacing all that
hose... I might as well replace the check
valves on the feed and the return....
and if so.... how close does the return
one need to be to the tank... it is in
a precarious spot right now..... If
it is within one foot of the tank...
is that ok....
You talk about the banjo bolt and
the bleed screw on the top of the
filter base..... My filter set up is
the newer style... C-clip and O-ring
no bleed screw..... Is there a bleeder
on the IP??
Yeah, those tiny worm clamps are
"for the worms" I think I am gonna
take you up on the single spreader
clamps... the worms ruin the hose.
and if you dont crank on them they
loosen up...
Yeah it would be nice to get a little
translucent plastic tubing.......
from the rear wheels to the front
of the vehicle is the plastic. I mean
it looks healthy still...
Here is another question for you..
The stuff on the car now is all oem...
so it is plastic and then the crip connect
to the rubber....... (like a pressure side power steering hose)
I was figuring I can cut it with a plumbers tubing cutter and
then get some of those tubing inserts to stick in the hose so it
doesn't collapse when tightened....
Does that seem to make sense?
and those inserts you think that is "go to the dealer stuff"
Also I noticed when I was messing with the hoses...
the connection for the (5/16 feed line) in the IP...
It has a bolt through it(banjo style) and the a little
nipple threads into the collar that the bolt holds donw.
well, the nipple was loose... I spun it (1/4 turn) with the
hose still attached... now it is tight but is it sucking air????hmmm
So what is the connection here at the IP about...
Could you describe it......
Two copper washers on the banjo bolt?
and this nipple? Is it really threaded??? Is it pressed in?
Is mine malfunctioning???????
thanks

hmm.. i doubt the nipple on the return line is causing problems, it should leak outwardly if it leaks at all. i'm familiar with the connectors that you have on your fuel system, but mine does not use them so i overlooked that. if the quick disconect type fitting is leaking it is possible to replace the o-ring inside, but for a diesel aplication you should look for neoprene o-rings because conventional rubber rings will degrade from contact with diesel. maybe viteron would also be an acceptable substitute. if you want to replace the rubber tube attached to the plastic tube make sure the two fit tightly and slide the rubber hose on about 2" and use two appropriately sized clamps (to insure the connection doesn't make future trouble). if the hose does not fit the tube tightly using any number of clamps will probably give a marginal seal at best, i doubt you'll need to use any type of insert to keep from crushing the plastic tube because pressure is applied equally around the the outside and directed inward.

just found out that a translucent tubing suitable for fuel is nylon and should be available from a hose shop, but you can order it from plastic suppliers if it is not available localy. the translucent tubing available from building supply stores (used to hook up ice makers) is not nylon unless it says specificaly. even that stuff will carry fuel, but it is not as resiliant as nylon, so i can't say i really recomend it.

not sure about check valves in the fuel system, mine does not have them (but it is kindof old) and i was not aware that the new ones did untill you mentioned it. as far as relocating them it is up to you, do whatever you are able to do; the location of a check valve matters less that it's inlet and outlet orientation.

about the banjo bolts, the inlet is near the timing belt, and the outlet is on top. the inlet probably won't leat outwardly unless there is a major break in the line. pay attention to major abrasion of the inlet line because most of the time that type of dammage won't look as if it would cause a leak even when it is the source of a leak. there is always the possibility of the pickup tube in the tank causing the problem, but if you decide to remove the sending unit mark it's orientation before removal. my brother once reinstalled the sending unit and ran out of fuel with the gauge showing 1/2 tank because the float was hung on the structure in the tank.