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Engine Specific Info and Questions => IDI Engine => Topic started by: stewardc on August 07, 2012, 03:25:38 pm

Title: Better fuel return hose
Post by: stewardc on August 07, 2012, 03:25:38 pm
Is there a better hose to use on the small injector return lines. I'm presently using the old braided-cover VW hose, but there must be something better. Like silicon, for instance ???
Title: Re: Better fuel return hose
Post by: vanbcguy on August 07, 2012, 05:00:15 pm
I've seen lots of folks using motorcycle fuel line or chainsaw fuel line with good results...
Title: Re: Better fuel return hose
Post by: 745 turbogreasel on August 07, 2012, 05:22:53 pm
Better for what?  The braid stuff is easy to install, and lasts a fair while.
Title: Re: Better fuel return hose
Post by: carrizog60 on August 07, 2012, 05:32:16 pm
why?
if its leaking probably its old,itīs always good to do proper maintenance and just replace that.
Title: Re: Better fuel return hose
Post by: libbydiesel on August 07, 2012, 05:48:25 pm
I use 1/8" ID clear tygothan from mcmaster.  Fantastic hose.  Super-resilient.  I now have a couple years of use on multiple vehicles and haven't ever had an issue.  It lasts much longer than the braided hose. 
Title: Re: Better fuel return hose
Post by: CRSMP5 on August 07, 2012, 05:57:01 pm
my 98 tdi that i used to bbuild my tdi-m from has lime green ones.. ive had them off and on the injectors a few times... aka during the build...

i decided to try them out... and over 13k later still no leaks with bio or diesel..

what they are.... rc nitro fuel line... lots of colors avalible.. cheap... most hobby shops that deal rc carry it... so need a little accent under the hood... there you go..
Title: Re: Better fuel return hose
Post by: stewardc on August 08, 2012, 12:45:08 pm
Wow, thanks for this guys. the Tygothane and the RC fuel line both look good.

When replacing, always look for something better than stock. OEM+
Title: Re: Better fuel return hose
Post by: R.O.R-2.0 on August 08, 2012, 01:40:03 pm
i use vacuum lines.. since i usually pull all the emissions equipment off my ricers, and anybody elses who wants me to take it off, i have a HUGE pile of vacuum line laying around.. i use it for damn near everything that takes small line..

boost lines, fuel return lines (it doesnt harden from the fuel or heat)
Title: Re: Better fuel return hose
Post by: mtrans on August 08, 2012, 01:55:15 pm
X2
I use ONLY this for all fuel line,its PA tupe.
Title: Re: Better fuel return hose
Post by: stewardc on August 09, 2012, 07:05:02 am
i use vacuum lines.. since i usually pull all the emissions equipment off my ricers, and anybody elses who wants me to take it off, i have a HUGE pile of vacuum line laying around.. i use it for damn near everything that takes small line..

boost lines, fuel return lines (it doesnt harden from the fuel or heat)

Isn't that just like what VW puts on them originally?

Title: Re: Better fuel return hose
Post by: R.O.R-2.0 on August 09, 2012, 02:35:37 pm
i use vacuum lines.. since i usually pull all the emissions equipment off my ricers, and anybody elses who wants me to take it off, i have a HUGE pile of vacuum line laying around.. i use it for damn near everything that takes small line..

boost lines, fuel return lines (it doesnt harden from the fuel or heat)

Isn't that just like what VW puts on them originally?



basically, but smaller ID, so it fits ALOT tighter on the barb than the braided shizz..

plus, its not braided, so the fabric doesnt bunch up on the ends, and make it about impossible to re-install the lines after re-using them 3 or 4 times..

fish tank air line works good for temporary diagnosis of leaks with the injector returns..
Title: Re: Better fuel return hose
Post by: gldgti on August 10, 2012, 02:30:31 am
I am using SS braided Teflon......its awesome, but I wouldn't do it if I had to pay for the hose first ;-)
Title: Re: Better fuel return hose
Post by: stewardc on August 10, 2012, 01:01:22 pm
I am using SS braided Teflon......its awesome, but I wouldn't do it if I had to pay for the hose first ;-)

Gave you got any pictures of that ?
Title: Re: Better fuel return hose
Post by: gldgti on November 15, 2012, 02:33:38 am
sorry stewardc, only just saw your reply. you can just see it in this pic...

(http://i167.photobucket.com/albums/u139/gldgti/P1010625.jpg)
Title: Re: Better fuel return hose
Post by: bajacalal on November 15, 2012, 11:53:00 am
I use the regular small fuel line. I think 3/16" is what fits. If you can't find it at an auto parts store try a small engine or motorcycle shop as mentioned.

I don't like the OE hose with the external cloth braid, I think it traps contaminants which cause the hose to wear, and it makes it hard to spot a deteriorated, cracked or leaking hose, because you can't see the rubber. If you buy hose that isn't rated for fuel, either silicone or rubber, it may dissolve in the diesel. I've seen this happen.
Title: Re: Better fuel return hose
Post by: stewardc on November 15, 2012, 01:11:30 pm
I like this, but what keeps the hose braid from fraying with no fitting on it ?

sorry stewardc, only just saw your reply. you can just see it in this pic...

(http://i167.photobucket.com/albums/u139/gldgti/P1010625.jpg)
Title: Re: Better fuel return hose
Post by: gldgti on November 27, 2012, 10:56:18 pm
just some electrical heat shrink :-) I cut the braid back about 5mm from the end of the inner teflon, and then put a 15mm piece of heatshrink over the end of the braid.
Title: Re: Better fuel return hose
Post by: fatmobile on November 28, 2012, 08:12:49 pm
I like clear lines between the injectors, for troubleshooting.
Title: Re: Better fuel return hose
Post by: millertime on December 17, 2012, 08:45:55 am
Im trying 1/4 air brake line, fits like a glove, looks cleaner and is super cheap, not every part store has it though, my local napa does but there the only ones, i think it was 1$ for 2 feet
Title: Re: Better fuel return hose
Post by: stewardc on January 03, 2013, 08:15:32 am
The line between the injectors is 1/8". Someone must make a better hose than that braided VW crap.
Title: Re: Better fuel return hose
Post by: TylerDurden on January 03, 2013, 08:26:19 am
Others have mentioned using vacuum lines from gassers.

I'm using Tygon transparent-yellow 4040A. http://www.amazon.com/Oregon-07-151-Fuel-Line-Tygon/dp/images/B0086OE0EE

Polyurethane comes in blue... http://www.amazon.com/Raider-717B-5-Roll-Fuel-Line/dp/B002ZTGLFM/ref=pd_bxgy_auto_text_z
Title: Re: Better fuel return hose
Post by: stewardc on January 03, 2013, 08:51:23 am
Many thanks. That's what I needed. ;D
Title: Re: Better fuel return hose
Post by: tyb525 on January 03, 2013, 09:05:57 pm
"Fuel and Lubricant Yellow Tygon PVC Tubing" 1/8" ID. Rated for diesel.

http://www.mcmaster.com/#standard-plastic-and-rubber-tubing/=kvqzrn
Title: Re: Better fuel return hose
Post by: 8v-of-fury on January 03, 2013, 09:13:29 pm
I ordered 15 feet of this (http://www.mcmaster.com/nav/enter.asp?partnum=5549K31). And 25 feet of this (http://www.mcmaster.com/nav/enter.asp?partnum=5549K46).

Flexible to -100F!
Title: Re: Better fuel return hose
Post by: vortexblue on October 26, 2013, 12:26:37 am
I ordered 15 feet of this (http://www.mcmaster.com/nav/enter.asp?partnum=5549K31). And 25 feet of this (http://www.mcmaster.com/nav/enter.asp?partnum=5549K46).

Flexible to -100F!

I just ordered these 2 part numbers. The smaller one fits fine, but the larger 1/4" - 5/8" is too thin. It doubles over and kinks too easy. I'll probably order something a little thicker.

I also ordered some spring clamps, but they mistakenly sent 16mm versions.   :P

I'll post up the part number if I find something. Thanks for the lead though!
Title: Re: Better fuel return hose
Post by: TylerDurden on October 26, 2013, 11:35:18 am
The 4040A is yellow, but you can see through well enough to detect bubbles.

1/16 wall seems ok here.

http://www.mcmaster.com/#5552k25/=p3scch
Title: Re: Better fuel return hose
Post by: stewardc on October 26, 2013, 01:03:41 pm
I tried the blue poly. NOT good. It blew off on a full-throttle run and soaked the engine in smoking, almost-ignited diesel fuel. I went back to the old tried-and-true VW braided hose. It may look poorly, but it has never blown off.
Title: Re: Better fuel return hose
Post by: fatmobile on October 29, 2013, 03:21:16 pm
It blew off of what?
 The pump output?
 Might have a clogged return line/check valve. There shouldn't be any pressure there.
 Did you use a clamp?
Title: Re: Better fuel return hose
Post by: 8v-of-fury on October 29, 2013, 07:19:09 pm
It blew off on a full-throttle run and soaked the engine in smoking, almost-ignited diesel fuel.

It will never catch fire, your safe lol. You can hold an open match to a puddle of diesel and it will not ignite.

There shouldn't be any pressure there.

There should not be any pressure between the injectors, or in any fuel line for that matter (except for the metal hard lines to the injectors).
Title: Re: Better fuel return hose
Post by: fatmobile on October 30, 2013, 03:35:47 am
 Right, that's why I'm wondering how it blew off.
 If you want to hose clamp the tubing it can pinch up and let more air in.
 I slide a piece of 3/8" rubber hose over the 1/4" ID tubing.
 Sliding the tube onto the barb then the rubber hose over that.
 A clamp works real well over the rubber hose,.. if one is needed.

 I'm a bit defensive about the blue tubing found at motorcycle shops. It works great for me.
 Throwing used motor oil in the fuel will sure make clear tubing hard to see through.
Title: Re: Better fuel return hose
Post by: 92EcoDiesel Jetta on October 30, 2013, 11:11:25 am
I think it's incorrect to say there is no fuel pressure in the return lines. Just the restriction of the small diameter line pushing fuel back to the tank results in some pressure . My guess a few psi, enough to pop the daisy chain lines if not a tight fit on the barbs.
Title: Re: Better fuel return hose
Post by: bajacalal on October 30, 2013, 02:10:14 pm
I've always used what I think is 1/8" diameter fuel line for the injectors and without problems. It's not clear. I get it at NAPA but you could try like a lawnmower shop too.
Title: Re: Better fuel return hose
Post by: fatmobile on October 30, 2013, 02:17:03 pm
I think it's incorrect to say there is no fuel pressure in the return lines. Just the restriction of the small diameter line pushing fuel back to the tank results in some pressure . My guess a few psi, enough to pop the daisy chain lines if not a tight fit on the barbs.

 Right, there is a small but measureable amount of pressure.
 If it's blowing lines something is wrong.
 MK2s have a check valve in the return line, that can restrict flow.
Title: Re: Better fuel return hose
Post by: 92EcoDiesel Jetta on November 01, 2013, 12:22:52 pm
I think it's incorrect to say there is no fuel pressure in the return lines. Just the restriction of the small diameter line pushing fuel back to the tank results in some pressure . My guess a few psi, enough to pop the daisy chain lines if not a tight fit on the barbs.

 Right, there is a small but measureable amount of pressure.
 If it's blowing lines something is wrong.
 MK2s have a check valve in the return line, that can restrict flow.

A clogged tank vent can also restrict return fuel flow and increase pressure. The OE braided return hose fits onto the injector barbs much tighter than the Tygon polyurethane tubings and less prone to blowing off. Hoses are layered/reinforced, tubings are not.
Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 01, 2013, 06:51:51 pm
What happened to those micro clips that used to hold the braided leak-offs-on?

Tyler why are you keeping your manometer reading-pressure-proof  to yourself? ;D
Title: Re: Better fuel return hose
Post by: TylerDurden on November 01, 2013, 07:16:40 pm
Bashful...  ;)

Oh yeah! There was a wee bit of pressure in the returns, even with the gravity draw toward the tank.

(https://lh4.googleusercontent.com/-ngfSCe_993w/URFzPjXc3dI/AAAAAAAAA_A/y5Gv6kWfjWI/s640/imagejpeg_2.jpg)

More here:
http://www.vwdiesel.net/forum/index.php?topic=32794.msg305024#msg305024
Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 01, 2013, 10:37:41 pm
Was that veg colouring or blood?  On this forum it could easily be the latter ;D
Title: Re: Better fuel return hose
Post by: TylerDurden on November 01, 2013, 11:11:06 pm
Nah... this crowd is a basket of kittens.

(The electric vehicle guys are another story.)
Title: Re: Better fuel return hose
Post by: libbydiesel on November 02, 2013, 11:36:27 am
The c-210-a clear tygon hose is better than the stock braided hose in every way.  It lasts much longer, is more resilient, much less prone to leaks, clear for easy diagnosis, rated for biodiesel, etc, etc...  I've used it on more than 10 vehicles now for several years without issue.  Those vehicles include Mercedes and VW diesels (each generation from mk1 to ALH).  I have also used it for boost fittings without clamps where it has seen greater than 25 psi without any issues of leakage or popping off.  
Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 02, 2013, 01:45:17 pm
Is there a 'best' tubing, for reuse purposes?
Periodic experimentation has me cutting the lines over-long to start with to get two or three reuses.
Clamps may have been the solution, but what the heck did I do with all mine ??? Only the one's on the boost remain...
Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 04, 2013, 09:32:21 pm

OK, so I convinced myself that clips were a good thing for tubing reuse, so I bought 10 of these. Hopefully 6mm ones will crimp down sufficiently; or I'll be reforging them ;)

http://www.ebay.co.uk/itm/Mikalor-W1-SPRING-BAND-TYPE-Fuel-Hose-Clips-Silicone-Pipe-Clamp-Low-Pressure-Air-/260952027955?pt=UK_DIY_Material_Nails_Fixing_MJ&var=&hash=item3cc1f3f333
Title: Re: Better fuel return hose
Post by: ORCoaster on November 04, 2013, 11:49:19 pm
Let us know how well they do the job.  I have gone to using very narrow zip ties.  I tried some thin braided copper wire but it cut through the rubber hoses and I wasn't any better off for it. 

I love the differences in our languages.  dispatched in one day.  That would mean they would be dead not mailed to you. 

So if you end up with a bunch of flattened pieces of metal you will know why.

Dispatched by Ball Peen. 

Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 05, 2013, 06:50:06 am

H'mm strange. :o Wrong clips... I hate those, or at least in the larger sizes... I bought these:

http://www.ebay.co.uk/itm/Mikalor-W1-Mini-Metal-Nut-Bolt-Fuel-Hose-Clip-Petrol-Diesel-Pipe-Clamps-Zinc-/140764926891?pt=UK_BOI_Industrial_Supply_Material_Handling_ET&var=&hash=item20c63e53ab
Title: Re: Better fuel return hose
Post by: mtrans on November 05, 2013, 02:40:41 pm
If you hate clips etc... like I do
like this 3 yr no problem,eazy conect-deconect
(http://www.dodaj.rs/f/M/Yk/3vqXpwZR/p3090004.jpg)
Title: Re: Better fuel return hose
Post by: wolf_walker on November 05, 2013, 08:25:03 pm
There is a VW part number for the clips to hold those bypass lines on.  I have it, somewhere...
Never seemed to need any and have never seen them on a motor but they were in the EPC somewhere.

Never needed anything but the old braided hose either myself.  I don't run alternate fuels and generally leave
em alone once I install em.  They last as long as it takes an injector to need a nozzle or longer with fuel being what it is
these days in the US.  Every time I see someone have something that isn't the braided cover line on there it ranks
right up there with a fram oil filter.  Not that there aren't folks that have made informed decisions on an alternate line,
but it's the exception rather than the rule in my experience. 

All that braided line isn't created equal either.
Title: Re: Better fuel return hose
Post by: mtrans on November 06, 2013, 02:15:22 pm
I do run alternate fuels,and that is PA plastic that is use for air brake in truck,good to 20 bar and 60 c,just for rwcord.
Title: Re: Better fuel return hose
Post by: 92EcoDiesel Jetta on November 06, 2013, 04:01:53 pm
There is a VW part number for the clips to hold those bypass lines on.  I have it, somewhere...
Never seemed to need any and have never seen them on a motor but they were in the EPC somewhere.

Never needed anything but the old braided hose either myself.  I don't run alternate fuels and generally leave
em alone once I install em.  They last as long as it takes an injector to need a nozzle or longer with fuel being what it is
these days in the US.  Every time I see someone have something that isn't the braided cover line on there it ranks
right up there with a fram oil filter.  Not that there aren't folks that have made informed decisions on an alternate line,
but it's the exception rather than the rule in my experience. 

All that braided line isn't created equal either.


Didn't know there are VW clips for the injector lines and would like to see a pic or p/n. The braided hose fit so tight on the inj. barb which has the same design as push lock barbs that you'll have trouble pulling the hose off without breaking it leaving a stub, I can't imagine why clips are necessary with the OE braided hose, which is very tough, much tougher than the clear polyurethane Tygon tubing. The only reason I use the polyurethane tubing is you can see through it. I did have one (clear polyurethane tubing) develop a crack at the injector barb and made a mess. I was very surprised as it also feels very tough but I guess not as tough as the braided hose. I bought the tubing from McMaster and as I recall the tag on it says it was made by St Gobain. I am switching back to the OE braided hose. Wolf Walker, who sells the best quality braided hose?
Title: Re: Better fuel return hose
Post by: wolf_walker on November 07, 2013, 11:18:40 pm
No idea, I thought it was weird too but I know beyond doubt I've seen a factory listing/diagram showing them for one of these old motors.
I'll try and dig it out of my overly nested VW stuff folder.

If the braided stuff isn't rock hard and baked on from years and years, you can usually press in above the barb and pull up slightly on teh lip
at the base of the barb and they will come on off.  If they are too hard for that they need to be cut and put back on, if you left them long enough,
or replaced.  Seen a lot of folks use a razor to cut em off and score the barb up, leaks after.  Annoying.  I burn em off before I cut em after making that
mistake once.

Title: Re: Better fuel return hose
Post by: 745 turbogreasel on November 08, 2013, 03:20:28 am
Ford/junkyard has return line spring clamps for the 7.3 too.
Title: Re: Better fuel return hose
Post by: Mark(The Miser)UK on November 08, 2013, 09:17:25 am
VW part no. (+N) 900 455 01        '5 x 8'

Those 6mm clips arrived, but are a little tight,on my 8mm o/d tubing, so ordered a length of externally braided 7mm.
Title: Re: Better fuel return hose
Post by: oldpoopie on November 08, 2013, 11:37:56 pm
Ive been using this viton hose from dudadiesel. Its black opaque, but works fantastic.

http://www.dudadiesel.com/choose_item.php?id=hose1