Diesel Knowledge / specialists

Skinner_87

Club Member
Hi Guys,

Any of the mechanic's on here specialize in diesels?

Problem with the van is two of the injectors are bubbling as they have a puddle of diesel around them. Its done this before but the injectors seals were said to have been replaced. A breather pipe running between each injector i notice is blocked at one end (with a screw this doesnt seem right but its Fiat so god only knows)

Any thoughts are appreciated.

(il probably end up tackling this myself tbh as a decent garage is becoming hard to find here!)
 

frank

Club Member
we had the same with our fiat van at work paul, it would fail the mot every year, i,ll ask at work later :)
 

James

Chairman
Problem with the van is two of the injectors are bubbling as they have a puddle of diesel around them. Its done this before but the injectors seals were said to have been replaced. A breather pipe running between each injector i notice is blocked at one end (with a screw this doesnt seem right but its Fiat so god only knows)
That sounds a similar setup to my old 406, the leak off pipes ended with a cap over the far right pipe. I remember running the car on veg oil caused this problem to be worse as the veg oil eats away at the rubber.

I changed the leak off pipes and it all seemed much better!
 

Low Rider

Poindexter
Moderator
Club Member
Hi Guys,

Any of the mechanic's on here specialize in diesels?

Problem with the van is two of the injectors are bubbling as they have a puddle of diesel around them. Its done this before but the injectors seals were said to have been replaced. A breather pipe running between each injector i notice is blocked at one end (with a screw this doesnt seem right but its Fiat so god only knows)

Any thoughts are appreciated.

(il probably end up tackling this myself tbh as a decent garage is becoming hard to find here!)
Bubbling where Paul?

The 2 typical leak paths I've had experience with are either down to the common rail fuel feed, (some clunk over tightening), or more the solid copper seal where the the injector body meets the combustion chamber. This is the usual cause of 'bubbling' due to cylinder pressure bleading back up to atmosphere. Once they're gone they only get worse. Saw a lot of failures in my times at Delphi and it's a pretty common thing on FIATs, so I've heard. Without seeing it first hand though it's purely speculation ;)
 
OP
OP
Skinner_87

Skinner_87

Club Member
Bubbling where Paul?

The 2 typical leak paths will be either down to the common rail fuel feed or more likely the solid copper seal where the the injector body meets the combustion chamber. This is the usual cause of 'bubbling' due to cylinder pressure bleading back up to atmosphere. Once they're gone they only get worse. Saw a lot of failures in my times at Delphi and it's a pretty common thing on FIATs, so I've heard ;)
"cylinder pressure bleeding back up to atmosphere" thats what i was told last time Dave sounds very familiar. You could right what i know about diesels on a match box tbh!

Its bubbling right where the injector is seated into the head, so sounds like the seals have died again! I believe most failings are common with Fiats :rolleyes:

Would these seals need to be annealed before fitting do you think?
 

Low Rider

Poindexter
Moderator
Club Member
They 'should' come pre-annealed. Opinions may vary but injectors need initial torquing, heat cycling, and then re-torquing as the seals give a little and do have the habit of failing prematurely if incorrectly torqued.
 

frank

Club Member
ours was the spill pipe paul, a nipple ontop with a push-on rubber pipe that weeped iirc :)
 
OP
OP
Skinner_87

Skinner_87

Club Member
They 'should' come pre-annealed. Opinions may vary but injectors need initial torquing, heat cycling, and then re-torquing as the seals give a little and do have the habit of failing prematurely if incorrectly torqued.
Ta Dave, in the time it took to "repair" them last time i doubt they were heat cycled before i got the van back!

ours was the spill pipe paul, a nipple ontop with a push-on rubber pipe that weeped iirc :)
Thanks Frank, sorted a workshop manual / copper seals & the piping for £25 .. bit of an oil leak too so its have the front stripped off & get stuck in save a few hundred quid!
 

Belly93

to turbo or new lump :/ hmmm
I work in a diesel specialist garage, the only injectors we torque down really are the vw pd injectors, but as said the bubbling is usually from the combustion gases leaking past the sealing copper washer between the injector cap nut and the cylinder head, if its left it can cause a build up of carbon around the injectors, we remove the injector give the hole a real good clean replace the copper seal and the refit the injector and run up to temp to enure its definitely not leaking
 

Belly93

to turbo or new lump :/ hmmm
That sounds a similar setup to my old 406, the leak off pipes ended with a cap over the far right pipe. I remember running the car on veg oil caused this problem to be worse as the veg oil eats away at the rubber.

I changed the leak off pipes and it all seemed much better!
Was this on an old style engine james?
 
OP
OP
Skinner_87

Skinner_87

Club Member
I work in a diesel specialist garage, the only injectors we torque down really are the vw pd injectors, but as said the bubbling is usually from the combustion gases leaking past the sealing copper washer between the injector cap nut and the cylinder head, if its left it can cause a build up of carbon around the injectors, we remove the injector give the hole a real good clean replace the copper seal and the refit the injector and run up to temp to enure its definitely not leaking
Ta Belly, all 4 were replaced 10 months ago (4,000) miles so id imagine the surfaces wernt cleaned properly, so they have failed quickly.

Though one of the injectors was swopped as it had a massive weld on the side of it from the previous owner!

im new to diesels, whats the safest way to depressurise the system? and would it need bleeding when its all back togeather?

Sorry for all the questions mate
 

Belly93

to turbo or new lump :/ hmmm
They dont bleed like old diesels, just pipe it all back up and either prime it with hand primer if it has one, or ignition on a couple of times before starting if it has an electric pump, and depressurization just loosen an injector pipe, its all i do
 

Belly93

to turbo or new lump :/ hmmm
If its like that paul they only need bleeding if you remove the whole injector pipe, and the srew in the end injector will be to stop it leaking diesel from the return pipe as it all leaks back through the pipes between injectors and out one end
 

frank

Club Member
pritty sure it is Frank, its a 2002 model. I remember them being quite stubby
yes ours was a 52 iirc like that, it looks like it is a taper seal type ? (no copper ring ?) and these ones self bleed i think mate, common rail ones usually need programming eh £££ !
 
OP
OP
Skinner_87

Skinner_87

Club Member
yes ours was a 52 iirc like that, it looks like it is a taper seal type ? (no copper ring ?) and these ones self bleed i think mate, common rail ones usually need programming eh £££ !
Id been on the fiat forum reading about that coding, was worrying as theres no fiat dealer here & thats an expensive boat trip to the mainland as well!

Your right, looks to be common rail only having a copper washer, so the smooth taper under the thread seals the diesel in?, would have though there would be some sort of seal!
 

Belly93

to turbo or new lump :/ hmmm
If you can get a pic of the injectors we can probably tell you what system is on it paul, :)
 
OP
OP
Skinner_87

Skinner_87

Club Member
If you can get a pic of the injectors we can probably tell you what system is on it paul, :)
Will do mate il get some snaps & maybe a vid tomorrow in the daylight, pain is the inlet mani has to come off to get to half of them!


Appreciate the help guys :)
 
OP
OP
Skinner_87

Skinner_87

Club Member
some sparkplugs are taper seal eh paul, no compressible washer needed
I live and learn eh Frank :) hopefully its something that will clean up & not the surfaces needing re cutting or anything like that... be different from working on a CG for a change
 

Belly93

to turbo or new lump :/ hmmm
Its not a fiat scudo is it? 1.9 4 bolts hold the mani on, glow plug wires bolted on the side with a 10mm, theres 1 or 2 vac pipes on the intake of the manifold, i may have forgot something, if its the one im thinking of it has a black plastic mani over the top of the injectors
 

Low Rider

Poindexter
Moderator
Club Member
Ah ok, they are completely different from the type I was thinking of, which are later pencil type units.

Over to the old skoolers, (I only worked on much later systems >1300bar CR & >3000bar EUP).
 
OP
OP
Skinner_87

Skinner_87

Club Member
Its not a fiat scudo is it? 1.9 4 bolts hold the mani on, glow plug wires bolted on the side with a 10mm, theres 1 or 2 vac pipes on the intake of the manifold, i may have forgot something, if its the one im thinking of it has a black plastic mani over the top of the injectors
Close mate its a Doblo Cargo but the setup sounds very similar!
 
OP
OP
Skinner_87

Skinner_87

Club Member
Its not a fiat scudo is it? 1.9 4 bolts hold the mani on, glow plug wires bolted on the side with a 10mm, theres 1 or 2 vac pipes on the intake of the manifold, i may have forgot something, if its the one im thinking of it has a black plastic mani over the top of the injectors
Hi Bud these are the injectors, as you can see cylinder 4 is piddeling diesel & cylinder 2 is damp!

 

Belly93

to turbo or new lump :/ hmmm
Just asked a lad at work paul hr says small bubbling isnt anything to worry about unless it starts to majorly buble the diesel leak could br the return between the injectors leaking especially if no 4 has a bolt in try replacing the joining pipe, and the blank on the end, they need to be the same length as original tho
 
OP
OP
Skinner_87

Skinner_87

Club Member
Just asked a lad at work paul hr says small bubbling isnt anything to worry about unless it starts to majorly buble the diesel leak could br the return between the injectors leaking especially if no 4 has a bolt in try replacing the joining pipe, and the blank on the end, they need to be the same length as original tho
Thanks mate il have a look at changing that pipe first then, im sure that pipe from no4 is alot shorter than when i got it, might have been cut down.
 

Belly93

to turbo or new lump :/ hmmm
Spoke to boss because he deals with the older ones the most, says the bubbling is normal, the leak could be from, the pipe ( also said length doesnt matter) the little return pegs on the injector have been damages when the injectors were removed or leaking from where. The 2 halvees of the injector join, i would try the pipe first, probably cheapest option too
 
OP
OP
Skinner_87

Skinner_87

Club Member
Spoke to boss because he deals with the older ones the most, says the bubbling is normal, the leak could be from, the pipe ( also said length doesnt matter) the little return pegs on the injector have been damages when the injectors were removed or leaking from where. The 2 halvees of the injector join, i would try the pipe first, probably cheapest option too
Ta lad just ordered a length of that pipe with a fresh bung for the end wash only a few quid, best to start with the cheap fixes as you say!

Il let you know how i get on, thanks for your help bud :)
 
Top