A4 Jetta TDI Clear Teflon Fuel Line/Injector Return Line Upgrade...

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Fellas,
Quite a while back I had issues with the dreaded air-in leakage effecting startability of my TDI. At that time I had the 01M transmission and from what I understand the automatic transmission equipt vehicles didn't offer the clear fuel lines from the fuel filter. Since my fuel lines were in bad shape, and I needed a clear section of tubing to help troubleshoot my air-in leakage issue I decided to come up with a solution that would work well long term and be temperature and chemically compatible. Here is what I came up with:

Above: I visited the junk yard and found a 2000-2004 Jetta gasser and extracted some of the fuel system quick disconnect fittings. At least two are needed but if you are like me and break one then it would be better to have three! :) Pay no attention to the ball snap-it's for another project;)
..
Below: Once you have the quick disconnect fittings the old plastic and rubber lines can be GENTLY removed. One end of the male quick disconnect has an O ring so be cautious!


Above: Once your disconnect pieces are prepared it's time to find some clear Teflon tubing. McMaster Carr has some Teflon PFA Clear tubing that is 8mm(.300-.315") ID and 10mm OD that will work well. The ID is the MOST CRITICAL dimension since it is what will seal on the O ring and stretch around the retaining hose barb. The product code number is: 5733K78 and the link is:

http://www.mcmaster.com/#5733K78



You will need at least 4 inches of it. While at the junk yard look for some stainless steel hose clamps on fuel and vacuum lines. Some types are reuseable and you can use a pair of piers to gently slide the SS clip ring apart and it will release. The clamps aren't necessary but I like the look and also knowing that it won't come apart. The clamp shown in the picture isn't in it's proper position which would be directly over top of the O ring on the male section of the quick disconnect.
..
Below: Here it is connected to the vehicle. I used some 5/16" ID "Weatherhead" diesel rated hose from NAPA since it has a stock-like cloth braid appearance.


I also got tired of dealing with replacing the rubber fuel lines connecting the injectors to the IP. I used some Teflon tubing on that too since it will take the heat and give me a way to see if my air is leaking through those areas! :) I used some smaller diameter SS clips on that also. I will take some measurements and see what diameter tubing would be needed for those line aswell:




Measuring the fuel injector nipples it looks like 4mm Teflon PFA Clear tubing will work. The 4mm stuff will have to stretch 1.5mm to go over the number 3 injectors barbs but is doable. Here is the McMaster link for it:

http://www.mcmaster.com/#5733K54


The total length needed for the fuel injector return lines will be minimum of 3 feet. That gives you 3.5" between each of the three injectors and then gives you about two feet for the return portion to the IP. By the way none of the line replacements interfere with the engine cover so that's not an issue either. I've had my clear Teflon fuel line quick disconnect assembly on for a couple years with absolutely no issues. I started converting the fuel injector return line a year ago and just finished replacing the last rubber piece of fuel injector tubing(piece between the last fuel injector and the IP a few weeks ago after I had a major blowout there which resulted in an engine/clutch that was completely doused with diesel! Now with the Teflon tubing I have no worries of fuel injector line leakage and can remove it from my preventative maintenance list. I really like the ability to see if there is air getting into the lines easily-this mod has removed a large percentage of where air intrusion issues actually happen.
 
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josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Here is a link to McMaster for the SS one time pinch hose/tube clamps for the fuel injector return line upgrade-you will need at least 9, but they come in packs of 25:

http://www.mcmaster.com/#52545K38


Also, here is a link for the clamps for the IP fuel line-you will need only two for the setup shown above but they come in packs of 25:

http://www.mcmaster.com/#52545K51
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
Post saved, definitely doing this in the coming months. Thank you. And BTW, I love McMaster-Carr!
I can't count how many times I've driven to will-call in Santa Fe Springs to pick up some needed item that couldn't wait.
They're great if you don't mind paying retail.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Nice mini-write up, and spotless engine bay.

Thanks fellas for the nice comments! I just wish the interior plastic and the black exterior paint held up as well!
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Just measured and updated the fuel injector return hose length needed on the original post. FYI Also, I don't see why for less than the cost of an OE replacement(over $100.00) one could have the Teflon replacements. Plus the Teflon won't yellow and obscure fuel/air bubble viewing ability as it ages like the OE.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
If you notice in one of the above photos I had the original black rubber fuel injector return line plug. I didn't like the idea of having all other fuel return lines done in the Teflon but not that stinking little plug on the end so I fired up my drill press and used it like a lathe. I used some 1/4" brass stock and a regular sized file and a micro file set and produced a brass plug that could be inserted in a small Teflon tubing section and pressed onto the fuel injector nipple. At least now I don't have to worry about that being a leak point, and it looks great too!
 

fierodough

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Joined
Mar 8, 2013
Location
Ontario
TDI
Beetle
What is that cable (looks like a ground) on the vacuum canister bracket top bolt on the head? I don't have that on mine (previous owner may have hacked that also...) where does it go to?

Thanks!
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Could the Teflon tubing be used to run from the filter to the injection pump.

Sure, don't see why not. One thing however that thicker walled teflon tubing is difficult to bend and the thinner stuff can kink/distort when bent too much. Large radius sweeping bends are the way to go which ever way you go. I really like the clear lines so I can see any air bubbles that may appear.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
What is that cable (looks like a ground) on the vacuum canister bracket top bolt on the head? I don't have that on mine (previous owner may have hacked that also...) where does it go to?

Thanks!

Your correct, that's just an extra ground I added when trouble shooting some time ago. I found the real issue(the corroded ground terminals below the battery box) and fixed it. I went ahead and left the extra ground since it couldn't hurt anything to have an extra.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
I'm thinking of ordering enough to do all my lines. It seems flexible enough, any reason not to just do the whole system in this?

The Teflon lines I have added are working superbly. They are super clear and hold up to heat and chemicals really well. Actually Teflon is inert to most chemicals and can take extreme temperatures. It can be a bit expensive but just doing your inter-injector lines, your return line from the injectors to the IP, and perhaps from the fuel filter to IP wouldn't hurt a bit. One thing to watch out for is that some of the lines they specify as "clear" aren't really that clear so make sure you are certain before you get it ordered. The tubing and SS clamps I specified above should work well.
 

drklawz

Well-known member
Joined
Nov 22, 2008
Location
Denver
TDI
2002 Golf HB, 4dr
Any updates?

Hey! - Any updates? I've been thinking about doing this swap while I have the injectors out.

MB
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Hey! - Any updates? I've been thinking about doing this swap while I have the injectors out.

MB

Yes, actually working perfectly. So well in fact, I'm considering doing the same when I replace fuel injector return lines on the Wifes 2005 E320 CDI :)
 

Bjar

Member
Joined
Aug 6, 2007
Location
Greenwood Lake, NY
TDI
99.5 Golf TDI with approximately 344000 miles!
I have a few questions about the pinch clamps,

http://www.mcmaster.com/#52545K38

What tool do you use to crimp these? Can you use the same tool that you would use for Pex plumbing cinch clamps?
http://www.pexuniverse.com/store/category/pex-clamp-tools
The pinch clamps you used look almost exactly the same as Pex cinch clamps, just smaller.

Or is this tool from McMaster-Carr the only appropriate tool?:
http://www.mcmaster.com/#pinch-clamp-pincers/=qj3by7

Would there ever be a need to remove the Teflon return hoses, and if so, how in the world do you take the pinch clamps off? Can you safely twist them off with vise-grips?
 
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MrSafety

Newbie at Heart
Joined
Jun 27, 2010
Location
California... Novato... 25 Mi. N. of S.F.
TDI
2002 Jetta TDI/ALH/01M-'80 240D Mercedes/'81 Rabbit "Caddy"/'99 Lexus ES300
josh8loop,
First let me compliment you for this THREAD and its many quality closeup photos!

My question(s) have to do with the Quick-Disconnect "elbows" you show:
Q1 - Are these OE parts?
Q2 - If not can you tell me your source for these ?

I'm working on my Son's 2002 TDI trying to replace the two 8mm fuel lines between the fuel filter and the rigid fuel lines coming up from below into the engine compartment... the ones that have quick-disconnect "elbows" that clip to the rigid fuel lines!

I purchased OE part 1J130295/A/D/E for only this elbow fitting... only to find it is too small to fit on the end of the rigid lines... so I'm mainly looking for an alternative source for these OE fittings on which I believe the internal O-rings are worn failed and now allow air to be sucked into one or both the fuel lines... a problem I'm sure you are all too familiar with!

I like your original project's intent to install a clear section of fuel line just prior to the IP and and will complete the same on his 2002 TDI soon!
Regards... and thanks again for you QUALITY POST !,
Sam Ross
 

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
Wow.
Wish I had seen this before my swap. I would have done it then for sure.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
I have a few questions about the pinch clamps,

http://www.mcmaster.com/#52545K38

What tool do you use to crimp these? Can you use the same tool that you would use for Pex plumbing cinch clamps?
http://www.pexuniverse.com/store/category/pex-clamp-tools
The pinch clamps you used look almost exactly the same as Pex cinch clamps, just smaller.

Or is this tool from McMaster-Carr the only appropriate tool?:
http://www.mcmaster.com/#pinch-clamp-pincers/=qj3by7

Would there ever be a need to remove the Teflon return hoses, and if so, how in the world do you take the pinch clamps off? Can you safely twist them off with vise-grips?

Yes, you should be able to use that tool or just use some end cutter wire cutters to crimp them like I do. Should you need to remove anything you can either gently wiggle the teflon hose/clamp assembly off the barb or preferably cut the SS clamp off and replace it later.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
josh8loop,
First let me compliment you for this THREAD and its many quality closeup photos!

My question(s) have to do with the Quick-Disconnect "elbows" you show:
Q1 - Are these OE parts?
Q2 - If not can you tell me your source for these ?

I'm working on my Son's 2002 TDI trying to replace the two 8mm fuel lines between the fuel filter and the rigid fuel lines coming up from below into the engine compartment... the ones that have quick-disconnect "elbows" that clip to the rigid fuel lines!

I purchased OE part 1J130295/A/D/E for only this elbow fitting... only to find it is too small to fit on the end of the rigid lines... so I'm mainly looking for an alternative source for these OE fittings on which I believe the internal O-rings are worn failed and now allow air to be sucked into one or both the fuel lines... a problem I'm sure you are all too familiar with!

I like your original project's intent to install a clear section of fuel line just prior to the IP and and will complete the same on his 2002 TDI soon!
Regards... and thanks again for you QUALITY POST !,
Sam Ross

Yes, these are OE components on the quick disconnect elbows. Review post #1 for my source of those. Remember those quick disconnect elbows have two O rings in them and a brass separator ring. Those O rings can be replaced with Viton O rings. The O rings are difficult to get out and you need to be careful not to pick them too hard with a pick tool otherwise you will damage the internal sealing surfaces. Also getting the brass separator ring in the correct spot can be difficult too. Purchase some Hylomar sealant like this from Autohaus AZ next time you place an order there and coat the mating/sealing surfaces of all fuel connections:

https://www.autohausaz.com/search/product.aspx?sid=qqjmjn453tfkbm45si004b45&partnumber=559526007

I've used that stuff for all my fuel line connections-fuel filter Tee included and the results have been very pleasing. The Hylomar is also diesel and related fuel additive compatible.
 

MAXRPM

Veteran Member
Joined
May 7, 2008
Location
US
TDI
00 Jetta and 99.5 Golf, 2015 Passat TDI,BMW 2
nice write up need to do mine sick and tired of replacing the oem injectors fuel lines. got to get this
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Yes, actually working perfectly. So well in fact, I'm considering doing the same when I replace fuel injector return lines on the Wifes 2005 E320 CDI :)

Just wanted to update. I have finished doing this on my wifes 2005 E320 CDI about 4 months ago. It looks really nice and works extremely well. My ALH with this mod is still working and looking great as well which is to be expected since it's a permanent fix. Just wanted to post feedback after the few years that I have had this mod in service :)
 

panthers89fan90

Veteran Member
Joined
Jun 11, 2014
Location
North Carolina
TDI
'03 Jetta TDI
I hate to dig up a grave here, but had a few questions.

I see you did the lines from the hard line to the fuel filter as well. What clamps do you use for the hard line portion of the fuel hose?

Also, I don't see an o-ring on the fuel quick disconnects. Where is this o-ring located?
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
I hate to dig up a grave here, but had a few questions.

I see you did the lines from the hard line to the fuel filter as well. What clamps do you use for the hard line portion of the fuel hose?

Also, I don't see an o-ring on the fuel quick disconnects. Where is this o-ring located?


The spring clamps I used are the same stock clamps used on the rubber lines that go on the fuel filter. I believe I ended up picking up a bunch of them from another VW at the junk yard. Also, the O rings on the quick disconnect are buried inside the female part of the QD fitting. You have to gently use a dental pick to coerse them out. There are a couple different types of fittings however and the ones you have may be a bit different than mine.
 
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