300Tdi injector leaking

chris snell

Administrator
Callsign: NW5W
Staff member
It's been a tough couple of weeks for my truck. It sat unused for a while and now practically everything that ever touched diesel fuel is springing a leak or broken. Fixed my lift pump, fuel filter, and spill tubes. Now I have what appears to be a leaky injector. It's pooling on the injector retainer and the block. I'm positive that it's not the spill tubes because those are new and fit tightly and they're not wet.

Has anybody seen this before? I guess it's time to order some new injectors. I've heard that they can be rebuilt--is there a mail-in service?

JuKaonu.jpg
 

DefendersNW

Well-known member
Check the tensioner and return line (spill) torque - replace crush washers on both sides of the banjo for the return, and the injector washer as well.

Leaky injectors usually leak into the engine, not outside.
 

chris snell

Administrator
Callsign: NW5W
Staff member
Good call. On closer inspection, it does appear to be coming from the banjos. I will order some new crush washers, spill hoses, and banjos just to be safe.
 

Viton

Well-known member
You could sand/file down the crush washers & give that a try.
But having spares on hand is always a good idea.
 

Roverman2010

Well-known member
If you are using copper washers (as you should) no need to get new unless they are damaged,

Heat up the copper washer till cherry red with a gas tourch or even a gas stove top and let it air cool. I use a lenght of copper wire to hold them while heating and cooling.

Re-annealing.
 

RDavisinVA

Technical Excellence Contributor
It's been a tough couple of weeks for my truck. It sat unused for a while and now practically everything that ever touched diesel fuel is springing a leak or broken. Fixed my lift pump, fuel filter, and spill tubes. Now I have what appears to be a leaky injector. It's pooling on the injector retainer and the block. I'm positive that it's not the spill tubes because those are new and fit tightly and they're not wet.

Has anybody seen this before? I guess it's time to order some new injectors. I've heard that they can be rebuilt--is there a mail-in service?

There are 2 types of spill over fittings for the 300TDI.
One has a straight metal pipe that originally had the crappy plastic spill over line.
The other has a serrated barb fitting.
The serrated barb fitting can take a push on rubber spill over line without leaking.
The non-serrated barb fitting is straight and will always leak when plain rubber spill over line is pushed on.

As mentioned above, the spill washer annealing advice is good, but if the the injector is scored or gouged where the copper spill-over washer seats, it will always leak until the damaged injector is replaced.

If you need a new set of 4 Bosch injectors for the 300TDI, we have them for $306 Shipped in USA via USPS (in limited quantity).
 

DefendersNW

Well-known member
PN is the same - whole assembly only from LR

Use Oetiker type clamps or a smaller tubing (I heat the stuff we talked about with a heat gun to get it to stretch over the piping)
 

chris snell

Administrator
Callsign: NW5W
Staff member
I will try some clamps. I need to get this thing back on the road quickly. If that doesn't work, I'll hit you up for a new assembly, Brian. Thanks guys.
 

RDavisinVA

Technical Excellence Contributor
My fittings are not barbed. Is there a part number for the barbed style?

You can try some small clamps, but those straight fittings are meant to have that shitty plastic line that gets brittle, cracks and leaks on it's own.
The serrated barb fitting is the only one that can take a push on rubber spill over line without leaking.
 

110user

Active member
I use viton line for the spill that there mercedes diesel folks like.

Never used a clamp and it's never leaked
 

broncoduecer

Technical Excellence Contributor
Went for a drive today and oddly enough ran into the same issue. Spill rail tube from 1 to 2 was leaking pretty good. I gave it a little tug and pulled right off. Chris - what did you end up doing?
 

javelinadave

Administrator
Staff member
I bought a meter of spill rail tubing from my local Mercedes Benz dealership for less than $20. I have no idea of the part number.
 

Napalm00

Technical Excellence Contributor
I use urathane motorcycle fuel line, it's clear blue and stretchy. Parts unlimited brand.

I have a boatload of you want some pm me and I'll mail it to you.


Not as kink resistant as the braided stuff but easy to work with.
 

RDavisinVA

Technical Excellence Contributor
I guess that VW Amazon line will work if you can cut it.
It sure is green.
Sometimes the outside of similar line is stainless and cannot be cut with dykes or snips requiring you to actually cut through it with a grinder and cut-off wheel.
This is because dykes will crush the metal and it will retain the flat shape where it is snipped and gets crushed.
If you grind through the line blow it out good with compressed air and push something solid through the line like a phillips screwdriver to clear the line of grind debris.

I sure don't miss any of the diesel BS with the this injector and that leaking IP and fuel starvation with other issues being long since in the rear view mirror.
Or the blown TDI head gasket on the way to MAR with a 110 packed with family and camping gear.

Had a friend in town that was undergoing a long trip that was having 300TDI EGT issues and was having to slow purposely down on upgrades because of it (wasn't like he had to help much because it's a TDI feature already).
When he started asking questions, won't mention the fine details of my answers.

But will say it is very nice to get into a 110 with a Chevy 250 and it starts and runs perfectly every time no matter how long it sat.
We have 2 TDI 110s owned by "diesel die hards" (like I was for 20 years) coming in this month for timing belts and tune ups and I just dread holding my breath hoping the timing cover bolts don't break off in the block like they usually do.
Then we'll have to pull the entire front off the engine and drill out and tap each frozen broken off bolt.
All this trouble for an under powered and unreliable TDI.
When will they learn?
When this happens it often can exceed the entire cost of a Chevy 250.
The road to practicality is often reached after first traveling the long route of pain and expensive repairs.
 
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