TD5 Injector Testing

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Many TD5 injectors get blamed,tested or replaced when there is nothing wrong with them. I have been asked to look at loads of them over the years where owners and garages have replaced injectors to cure rough running issues,with no improvement.
I scope the current draw of the starter motor to get a very accurate compression test.Nine times out of ten the engine will be down on compression on one or more cylinders.New injectors cannot repair bent rods,stuck piston rings or cracked pistons etc.(So do this compression test first before having injectors tested or replaced)
Also the cylinder balancing shown on diagnostic tools such as Nanocom or even Testbook are not that accurate on a TD5, unlike the injector compensation values on a TD4/6 Freelander or L322 engine which are much more useful.
I appreciate this was a long time ago, but y9y seem to have an understanding of the td5.

Would you be willing to elaborate on your starter motor test? What would one look for? Hi amps low amps? What should the normal range be?

My defender is running like a dog right now smokes so bad bond would be proud. And is down on power.

It's difficult to start and often requires easy start or the like.

On start it produces clouds of gray smoke that then changes to brown when reved ass the engine picks up and transition to a blue black grey colour under load.

Pointers would be extremely appreciated.
I can't put it to a garage as I simply do not have the budget so will have to do it my self. I could really do with some tips
https://youtube.com/shorts/CAIuQhxc6-8?feature=share
https://youtube.com/shorts/kYmCIUmIApU?feature=share
https://youtube.com/shorts/Hs2qsgouaIE?feature=share
Above are some links to how it runs
Thanks.

John
 
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Just joined this site and the above thread is very interesting, I have a TD5 for just under 4 weeks,
I have fuel oil getting into the lube oil and the oil level is rising.
I have had the injector seal replaced but it is still happening so the garage has told me that I need a
new head ( not personally, on second thoughts maybe I do).
Reading this thread I have a question, if one or more of the injectors is putting more fuel into the cylinder
than it should, is it possible for the excess fuel to run down the bore past the oil scraper and into the sump?
Just a thought.
 
Just joined this site and the above thread is very interesting, I have a TD5 for just under 4 weeks,
I have fuel oil getting into the lube oil and the oil level is rising.
I have had the injector seal replaced but it is still happening so the garage has told me that I need a
new head ( not personally, on second thoughts maybe I do).
Reading this thread I have a question, if one or more of the injectors is putting more fuel into the cylinder
than it should, is it possible for the excess fuel to run down the bore past the oil scraper and into the sump?
Just a thought.

The only way for fuel to mix with the oil is via the injector sockets - either a failed O ring or cracked injector socket. I believe on the early 10P Td5 there was also an issue with the internal fuel return gallery cracking, but I don't know if that would also cause fuel in the oil.

If you took it to a garage for the injector seals then they should really have checked for cracks on the sockets. Have they told you why they think it needs a new cylinder head or which injector sockets are cracked?

Excess fuel would not make its way to the oil.
 
The answer to that question is that I took it to the garage because of the fuel getting into
the sump, they told me it was the seals on the injectors, so I put it in to be done.
Two after I had it back the sump oil had risen dangerously so, I took it back to the garage
and they said if it wasn't the seals the ONLY other thing it could be is a cracked head????
 
The answer to that question is that I took it to the garage because of the fuel getting into
the sump, they told me it was the seals on the injectors, so I put it in to be done.
Two after I had it back the sump oil had risen dangerously so, I took it back to the garage
and they said if it wasn't the seals the ONLY other thing it could be is a cracked head????

Yes that's true but have they actually checked? It is not unheard of for people to damage the O rings fitting them. I wouldn't rush out and buy a brand new cylinder head unless the crack is identified. Unless they are going to replace the head and only charge you if it solves the problem!
 
Yes that's true but have they actually checked? It is not unheard of for people to damage the O rings fitting them. I wouldn't rush out and buy a brand new cylinder head unless the crack is identified. Unless they are going to replace the head and only charge you if it solves the problem!
+1... a friend of mine had new o-rings fitted and they leaked then on a comparison with the old ones the new o-rings were thinnner and that happened to others too so it's possible to be a bad batch too
 
I went to another garage owned by someone who knows a friend of mine today, who runs a
4 x 4 shop called Rugged 4x4 in Liverpool, they told that if the car is hard to start then it's
more than likely the injector seals. But if it starts without a problem then it points to a cracked
head and they gave me some tips on buying another one.
Does that make sense to you guys? (who I trust more than a garage by the way).
 
Another evidence of incompetence of some people who are running shops for profit. When we speak about injector "seals" there are two things involved: the copper washers which can cause hard start or missfire by letting combustion gas into the fuel rail and the o-rings which can let fuel from the rail into the oil so one doesnt exclude the other which means that the fact that it starts well has nothing to do with the fuel in the oil nor vice versa, see the pic maybe you can see what i mean

Td5_Cylinder head_washers.jpg
 
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The td5 engines can be a pig of an engine when it wants to be, that’s why I always recommend genuine parts now when it comes to engine and fuel parts (inc coolant) as there seems to be an issue with aftermarket parts even oem these days,Shame really
 
Discodevon, good picture, I understand, a lot different from the old Dorman/Blackstone etc big diesels I worked on in the 80's/90's

But from an absolute dumbo on the TD5, I have another question, I am looking for another head, is the 15p a diesel only head?
 
Another evidence of incompetence of some people who are running shops for profit. When we speak about injector "seals" there are two things involved: the copper washers which can cause hard start or missfire by letting combustion gas into the fuel rail and the o-rings which can let fuel from the rail into the oil so one doesnt exclude the other which means that the fact that it starts well has nothing to do with the fuel in the oil nor vice versa, see the pic maybe you can see what i mean

View attachment 269432

Get yourself on Facebook you can see some really bad advice being given out o_O People with starting issues being told to check their oil for diesel as it could be injector seals...... :eek:
 
Thanks tom1979, I think I have the hang of TD5 heads now, not an expert but more knowledgeable than I was
before. One observation though, I notice that the top 'O' ring is green, we use to use green 'O' rings when we
were servicing BA equipment if it was used on oxygen, as the were O2 compatible for preventing burning, is it
the same reason?
 
Hi Guys, Just to let you know my part on this thread is now finished (at least for the time being),
bought a recon head and a garage has agreed to fit for me.

Many, many thanks for all your help, it has been interesting and I learnt a lot about the TD5.
 
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