diesel fuel leak

dieseling

Well-known member
Joined
Apr 30, 2002
Location
Tx
TDI
Jetta 02 silver
I have a slight leak at #2 injector from either the steel fuel line or possibly the small black hoses.Car has stock injectors never touched.Tried tightening line, very tight.
Is there an o-ring at connection from fuel line to injector?
Hesitant to bring to dealer.
2002 Jetta TDI.
 

weedeater

Top Post Dawg
Joined
Mar 17, 2001
Location
Reston, VA
TDI
Jetta, 2001, Baltic Green
How many miles?

There's a washer, I think.

Is the black rubber hose wet? The black hose is the usual source of leaks. The rubber degrades due to heat and vibration. They are simple to replace. The hose clamps are not really required since the line is not pressurized. At least not that much.
 

dieseling

Well-known member
Joined
Apr 30, 2002
Location
Tx
TDI
Jetta 02 silver
I have 35000 miles
the fuel line nut is slightly wet the rest of the injectors
just looks dirty. car runs fine.
With all the people changing injectors somebody must know
if its an o-ring or compression seal at the injector fuel line.
 

cattlerepairman

Veteran Member
Joined
Jan 22, 2003
Location
Ottawa
TDI
none
I BELIEVE it is a copper compression washer. I also BELIEVE to have read that by taking the washer, heating it up till it glows and cooling it down in water, it returns to its original shape and seals like new.
 

Kennedy

Veteran Member
Joined
Jul 22, 2002
Location
Fredericksburg, VA
[ QUOTE ]
I BELIEVE it is a copper compression washer. I also BELIEVE to have read that by taking the washer, heating it up till it glows and cooling it down in water, it returns to its original shape and seals like new.

[/ QUOTE ]

NO... The compression washer provides the seal between your head and the injector (during compression). Spray some water on the seam (where the injector and head meet), and look for bubbles. If you see bubbles, you have a small compression leak. Tighten the 14mm bolt 1/4 turn.

If you are leaking diesel fuel tighten the nut where the fuel lines meet the injector. I believe a 17mm crows foot is the easiest to manipulate. There's no O-ring or anything like that.

If your injector return lines are leaking, replace them with some 1/8 internal diameter, 3/8 outer diameter VITON tubing from McMaster.com. 1 foot ($18, not cheap) will do the whole car... It's biodiesel friendly and should last forever.

If you change injectors, I've found you should tighten these at leats twice, as the heat cycling tends to loosen both.
 

mwalters

Veteran Member
Joined
Nov 10, 2003
Location
SE Michigan - Have VCDS
TDI
Jetta TDI 2013 Tornado Red
There's no gasket on the fuel line to injector connection. It has a built-in ferrule (sp?) in the steel line. Double-check the little braided cloth lines. They tend to deteriorate rather quickly. They allow excess fuel to flow back to the pump - not high pressure.
 
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