howto: 200tdi injector refurb

Good evening lads and lasses,

I had my injectors checked out properly earlier on today, on a very nice £14,000 bit of Bosch testing equipment. It's shown that three out of four nozzles are well past their best but instead of paying the usual £200 - £250 for reconditioned units, the technicians walked me through how to disassemble and and then re-assemble my injectors with new nozzles in a D-I-Y fashion. I have ordered a set of four nozzles at a cost of £80 from another local diesel injection specialist. He tells me that these nozzles are made on the same line as the genuine Bosch components in a Bosch factory but are un-branded. I don't really believe that but I'm willing to give them a try, with a saving of £86 over the Bosch nozzles. I have already cracked open and ultrasonically cleaned every component of two of my injectors and I intend to do the other two tomorrow. All being well, the new nozzles should be ready for me to collect on Monday and then all I have to do is whip the end caps off, lift my old nozzles out and slip the new ones in I'll let y'all know how the engine goes after I've re-fitted the injectors and all being well I'll have done just as good a job as the man in the workshop for a lot less money.

Here are a few pictures I took just for reference. Don't worry! They have been re-assembled in a pristine clean environment, not the horrible splintery, dusty outside area that you can see in these pictures. Also, one of the components is out of place in these photos. I found this when I tried to re-assemble the injector and the internals just rattled around. That problem is now solved.

The results for each injector as provided by the Bosch testing equipment. As you can see, the wear is pretty even which means there is nothing untoward going on inside the body, just general nozzle wear:









Cracked open the first injector. Quite simple really. Support the injector body in a vice ensuring that the jaws are only contacting the flat surface of the injector and then use a deep 15mm socket to crack the end caps / nozzle holders off. Three were relatively easy, one took a bit more effort but they all cracked off without too much hassle. I was surprised to see how many solid / gritty particles there were inside what I would have expected to be a very clean, well lubricated environment:







Old Nozzle wear is clearly visible towards the end point of the needle. This wear (as well as the wear in the nozzle housing) is what reduces the 'pop' pressures and diesel spray pattern in my case. I expect that when I install my new nozzles, the lack of wear should bring my pop pressures back up to where they should be and obviously restore the spray pattern. I suspect they have never been changed before, so they could well have covered 100,000+ miles:



Reassembling the injector after ultra-sonic cleaning. I took Buster's advice in the end and decided to go ahead with my mums el-cheapo ultra-sonic jewellery cleaner and the results were stunning. Simply put hot tap water into the bowl along with some of the jewellery cleaning solution that came with it, turned it on and suddenly clouds of black carbon come swirling away from everything inside! It only works on 3 minute cycles but I found ten cycles (30 minutes) was more than enough to bring everything up nice and clean (i.e. the solution barely sooted up). I have also cleaned and re-installed the old nozzles just so that everything is kept in place inside the injector body. All that needs doing now is the cap removing, the old nozzle removing and the new one fitting in its place. The new nozzles should be ready for me to collect on Monday, so I'll post more then :



-Pos

well I have just taken my injectors to a small diesel engineer for testing and/or repair and was told (depending on what was needed) costs would be between £12 and £50 per injector, needless to say it was the latter and I came home with 4 (New looking) injectors, but with £234 less in my wallet. Hope it will be worth it.

ormondstreet said:

well I have just taken my injectors to a small diesel engineer for testing and/or repair and was told (depending on what was needed) costs would be between £12 and £50 per injector, needless to say it was the latter and I came home with 4 (New looking) injectors, but with £234 less in my wallet. Hope it will be worth it.

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That's exactly the reason why I'm having a go at it myself! Were you experiencing power loss at all, or did you just want to have them checked? Could you let me know what difference it makes to your power when you get them fitted? Only one of my injectors had an acceptable spray pattern and I was told that it will make a tremendous difference to power and economy.

-Pos

I'm in the middle of a 19j to 200Tdi swap and wanted to do some prep of the new engine, when I fit it (about mid august) I will let you know how it runs.

mite be useful to have this in the general Q's and A's bit please

The Mad Hat Man said:

mite be useful to have this in the general Q's and A's bit please

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Finally! I may well actually have done something of use on here This is still a bit of a work in progress at the moment and all being well, if the end results are good, I'll do a more detailed right up with some of the steps in between. I thought it would be interesting for everyone to have a look at anyway. The Internet seems to be very scarce of anything related to dismantling and reconditioning Land Rover injectors, particularly 200TDi units which are very expensive in comparison to the closely related 300TDi injectors.

-Pos

as an aside - can yu fit a 300 head on a 200, or 300 injectors into a 200, coz I thught the injuns were basically the same block?

The Mad Hat Man said:

as an aside - can yu fit a 300 head on a 200, or 300 injectors into a 200, coz I thught the injuns were basically the same block?

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Not so easily, there are subtle differences unfortunately. 300Tdi injectors, although they look pretty similar to 200Tdi injectors (there are visual differences) are built with different rated components. The nozzle holes are located in different locations so that the atomised diesel spray is aimed towards the more central combustion chamber on the 300Tdi piston crowns. A 200Tdi has combustion chambers which are off-set, either more towards the left or the right hand side of the engine and the 200Tdi nozzles are designed to suit. 300Tdi injectors also open at different primary and secondary pressures, both of which I believe are slightly higher than those of the 200Tdi (it could be the other way around) but I imagine you'd only have to swap the springs in order for this to be rectified. The 300Tdi injectors are also mounted slightly differently to the 200Tdi injectors, both in the angle that they sit in the cylinder head and in the height of the face which the securing bracket holds in the injector down into the head. This can apparently be solved via the fabrication of brackets although I've never found any information / photos about a few that already exist.

As for the 300Tdi head onto a 200Tdi, it's possible, even the head gaskets are identical. The only differences that I'm aware of are the rockershaft, push rods and manifold mating surfaces, all again which could have work arounds. The cylinder blocks are also different in terms of lift pump and oil filter locations but I'm not sure about any of the top surface stuff like push rod holes and cam shaft / followers etc.

-Pos

A nice new set of Italian made 'Firad' nozzles arrived today, ready to be installed into my 200tdi injectors. Information regarding this manufacturer was very scare on the internet, but the few gems which did show up as the result of a google search proved the brand to be both reliable and well made. (see website - ::FIRAD RESTYLING::) Fitting the nozzles was easy, I simply whipped off the end caps / nozzle holders, removed the old nozzles and installed the new ones in their place. The end caps are only formed from a thin steel alloy, so they just need to be nipped tight;- there's absolutely no need to get a breaker bar on there, just a 15mm spanner to nip them up and then tighten them up an extra 15-20 degrees.

I installed al four injectors with new copper sealing washers and new copper leak off washers and started the engine. It fired up after a little priming and, like a giddy child, I took it for a test drive. The results are tremendous :d The increase in torque is extremely noticeable, pulling away from 30 in 5th is a painless task and the power on hills has been doubled. I also noticed that the engine idle is a lot smoother and engine noise has been reduced. It is smoking a little, so I'm going to adjust my fuel down slightly tomorrow and play with the diaphragm until I get it spot on.

Generally speaking though, it has been a very worthwhile experiment, with similar results (I expect) to those that you'd get from a Diesel mechanic who might charge you anything between £200 to £260 for injector reconditioning. The total cost to me for the refurb has been £87 for a set of four nozzles. I also had use of my Mum's ultrasonic jewellery cleaner, something which I believe is essential to ensure that you get the internal components of the injector as clean as possible.

I'm going to give it a good weeks test and then take the injectors out for testing again. All being well, they'll be on the mark and then I wont have to worry about them again, well, at least not for another 100,000 miles or so.

-Pos

Good write up POS!

Just an update:

I put my injectors to a real test today, driving my 90 up a very long and steep hill a few miles away from my house. This is the hill that I used to gauge my engines performance deterioration over a period of weeks, decreasing from a good pull at 45 in fourth to a struggle at 30 in third, a power decrease which was more in keeping with my old N/A. Well today, my 90 pulled like a train and continued to accelerate all the way up to 50 in fourth and my foot was only half way down, so I'm very happy

On another note however, three of the four injectors appear to be weeping diesel from around the nozzle holder / end cap. This is effectively allowing diesel to drip into the bores, creating an erratic idle, excessive smoke and it'll almost certainly be reducing my performance quite considerably. Letting my engine run like this will cause piston damage quickly and it'll help to glaze my bores so I've taken immediate action.

I have read about a similar problem on an injector refurb topic on a Mercedes forum previously (http://www.dieselgiant.com/mercedesinjectornozzlereplace.htm), the main cause being purely and simply poor cleaning of the nozzle holder before the new nozzle was installed. Any carbon deposits that are not removed from the nozzle holder create high spots or 'gaps' between both the nozzle body and the nozzle holder mating surfaces. This gap is quite obviously vulnerable to leaks when fuel is pumped into the injector bodies at very high pressures.

I removed all four nozzle holders to inspect for carbon deposits and I have to say I did a ****e job of cleaning them when I first stripped and rebuilt my injectors. This time around I used a musical recorder cleaner type thing and a wad of steel wool. The ultra-sonic cleaner also came in very hand again, removing loose / stubborn carbon deposits quickly and efficiently. I have re-assembled all four injectors again and all being well this should have solved the problem. If not, I'll order four new nozzle holders and have the diesel man fit them so that if they leak again, he can sort them

I'll report back to base tomorrow once I've refitted them and taken the bugger for a blast.

-Pos

Also, does anyone have a decent method for cleaning the injector holes in the head? I've just been using some kitchen roll wrapped around the end of a screw driver but its a pain in the arse and it takes ages to get them really clean.

pos said:

Also, does anyone have a decent method for cleaning the injector holes in the head? I've just been using some kitchen roll wrapped around the end of a screw driver but its a pain in the arse and it takes ages to get them really clean.

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Those ear bud thingys you use on your kids to perforate their ear-drums work well..

storm99 said:

Those ear bud thingys you use on your kids to perforate their ear-drums work well..

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I tried but they aint long enough! I suppose I could selotape one to the end of a screw driver. I'd be shafted if I dropped it through the hole into the cylinder though I still use cotton buds to clean my ears.

An old knackered injector?

The Mad Hat Man said:

An old knackered injector?

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No..he might damage his ears.

Use a straight cut wooden dowel about the same diameter as the injector hole. Clean it up to minimise flakes of wood that may fall off. Put a little bit of oil or diesel on it, put it down the hole and role is between your hands, it will lightly abrade the carbon and clean it all up, if any carbon or wood dust falls into the engine it will be destroyed when the engine fires up and blasted out the engine as smoke.

Cheers for the tip Disco. The new nozzles and ultrasonically cleaned internal injector components have covered around 2,000 miles since I installed them last month. The performance has increased tenfold, with improvements to fuel consumption and much improved torque through low to high revs. It flies up hills without hesitation and the engine idle is much smoother.

For anyone who has an engine which has covered over or around 100,000 miles without any fuel injector attention, I'd strongly recommend that you get them tested, because they wont be performing as well as they could. Have a go at it your self, or have them refurbished by a Diesel Specialist (although it'll cost you three times as much) and see what it does for you.

-Pos

Did you change the needles as well as the nozzles or just the nozzles?

Shifty1962 said:

Did you change the needles as well as the nozzles or just the nozzles?

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Which part are you referring to when you say needle? The plunger with the tapered end that sits in the nozzle body or the short dowel like needle that is assembled further back inside the injector? Use the photo below as a reference:



-Pos