TD5 head advice.

Well, after argueing the toss with the dealers, and still having no joy, the head is coming off the Landy on tuesday.
I've talked to the lads at the local engine shop, and they agree with my diagnosis and will skim and pressure test it when it's off.
I'm no stranger to the inside's of an engine, but I am unfamilliar with this one so any advice given would be greatly appreaciated.

I'm going to replace the radiator, as this has sign's of Radweld being through it, and I shall flush the cooling system out.
The book show's 2 locking tools for the head and gearbox, would you recomend getting them or is there an alternative method?
I know the injectors are coded and must be kept in order, and cleanliness is the order of the day.

Is there anything else I should be aware of?

Thanks, Rob.

Hi Rob
you probably could do it without the proper spanners but I think it will probably be far easier with, and you run less risk of slipping off and putting a hole in that nice new rad, in fact I've just ordered the spanners myself from www.DIFFLOCK.com cos they sell them for 20 odd Quid as opposed to LR's 70 odd

it appears the Difflock store has closed since I ordered my spanners but they have an Ebay store

Are you thinking about skimming a TD5 head?
There is absolutely bugger-all clearance available between pistons and valves in these engines, and if you skim the head the valves will be closer to the pistons by whatever you skimmed off.

I recall that this head-skimming practice is expressely ruled OUT by LandRover, which means damn-all really unless there just happens to be some reason why the job is bound to end in disaster.

Before you do it, find someone WHO HAS DONE IT with good results - and ignore any experts who know better but have never done it.

Make sure you get two STEEL dowels for locating the head - the OEM plastic ones are no good and are the usual cause of HGF.

Extreme patience tightening down the head progressively helps to produce a sound HG joint.

CharlesY

CharlesY

Thanks Charles, just pricing up the tools to lock crank, cam, and remove injectors seals etc, already upto over £200, local landy specialist giving me a call later, might as well ask how much to do the job, let him have the headaches.

Wifes just dropped the bombshell that the MOT's out on her's now, so down to no cars... hope next time a black cat crosses my path I'm in the Disco....

Rob

You don't need most of those tools.

DO NOT MEANTIME UNDO THE INJECTOR ROCKER ADJUSTERS!
You almost certainly will NOT need to touch them, nor to buy new bits.

I changed my injector washers with NO special tools being involved, and I did not undo the injector rocker adjuster screws either.

Use a thin bladed knife to pop the old washers off the injectors.
Use a micrometer or digital caliper to measure how thick they are.
You do NOT want the new washers THICKER than the old ones by more than a couple of thou or so, but a new ones a few thou THINNER would be OK.

Do you understand why this is important? Let me know if not.

The rubbery O-Rings are easy fitted without the tool - probably easier than with it! Grease them a tad and carefully roll them into place.

MY TIP for the copper washers is to take the shine off them both sides by rubbing them up (towards the handle) the surface of a fine sharp FLAT file TWICE each side turned about 90° between rubs to cross-hatch the surfaces a tiny bit. Next lightly DEBURR the sharp edges of the holes in the washers both sides with a sharp knife. Now rub a little RED HERMETITE onto the cross-hatched faces of the washers and hang them up on a wire till fully dry. Rub the RedH well in, but don't use enough as will squish out - just enough to make 'em red and no more, but let it dry out.

Now use THINNERS on a rag and a stick to clean the seat in the head, and the seat on the injectors. LET THEM DRY OFF perfectly dry.
Grease around the O-Ring with simple plain yellow grease. Fit the injector fully in and clamp it down immediately using a torque wrench.

Check the torque lots of times! The injectors may seat down after a little time during the job , so expect to move the securing bolts down a tad. The more DOWN the injectors go, the better.

The rest is as per RAVE I guess.

CHarlesY

Hi guys, I have found all your TD5 Cylinder Head experiences very,very interesting. My 2003 Disco-2 Auto TD5A engine oil level has risen over the last few months, being 20mm over the dipstick full line now.

Having read the workshop manual, I guess I have one (or both) of the following problems.

1. Cylinder head is cracked through the internal diesel fuel flow or return galleries.

2. An electronic unit injector (EUI) rubber o-ring is leaking diesel fuel up into the camshaft/rocker cover, where it is draining down to the sump with the returning engine oil.

I found your above advice on fitting/refitting the EUIs into the cylinder head very valuable, so many thanks.

As our Disco has only covered 20,000 careful miles, I am very disappointed to experience this problem, as the Disco starts and runs so sweetly, with no overheating or smoke, and returms 25 to 30 mpg. No other under-bonnet fluid levels have dropped at all.

Have any of you come across this fuel/engine oil mixing problem, and do you think such a small fuel leak would be visable if the Cam/Rocker cover was removed? I cannot think of any other way to track exactly where the contamination is happening.

How very annoying.
If the engine oil level rises, bottom dollar bet is diesel contamination.

LOGIC.
You say the engine is running fine. So, chances are the injector copper washers must be fine, and the head gasket too.

Fuel contamination into the sump could be a spli head, but I don't think that's first bet. An injector O-Ring should be suspected.

I have not done this (yet ...!) but I think you have a chance of spotting the culprit injector. Take off the cambox cover, and very gently clean around the tops of the injectors. You could use an air-line with a probe if you were careful. You are not going to start the engine with the lid off.

The TD5 runs up full fuel pressure as soon as you turn on the IGN key, and you can make it do this for an hour if you choose to, so you can get the fuel pump running and keep it running at full 60 psi pressure while you watch the injectors to see if you can spot which one (if any) seeps fuel up the joint between the injector and the head casting - immediately above the O-ring.

The procedure would be to get a reliable chum to turn on the key to get the IGN lights on BUT NOT OPERATE THE STARTER, and the fuel pump will fire up.

When it stops, leaving the IGN ON all the time, your chum presses the throttle pedal to the floor and up again FIVE times. Each time he does this the fuel pump will start again and run fer several minutes. I guess it might take a few minutes to spot a diesel seepage, but I reckon if it's an O-ring gone, you'll spot it.

If you were very careful you could clean out most of the oil in the top of the head to make it clearer to see.

Let me know if this works!

Diesel fuel in the oil will not pose an immediate risk to the engine BUT the usual risks of over-filled sumps apply, and the viscosity of the oil will go down sharply.

Best fix it, but best without taking off the head.

CharlesY
CharlesY

Thanks very much for your helpful and prompt reply CharlesY. I usually hear the electric fuel pump in the tank start up before starting the engine, but I had clean forgot it would be a good way of pressurising the diesel injectors without running the engine, so again - many thanks.

I have been looking at diagrams and pictures of the fuel injectors, and I think a third possible route for fuel leaking into the camshaft/rocker area may be possible: Diesel fuel under full (running) injection pressure may escape up through the injector stem/pushrod body itself and into the camshaft/rocker area.

Unfortunately, I guess the only way to check this out would be to run the engine up without the camshaft/rocker cover in place, a little messy I guess with engine oil splashing everywhere, making spotting small diesel leaks very difficult.

When I tackle the job in the future, I will keep you fully informed.

For more information on TD5 Diesel Fuel to Engine Oil contamination, there are many more cases on the Land Rover Addict Website Forum . There is a case where the local Land Rover company contributed to the cost of a new cylinder head. The Land Rover Addict Forums are now located at

Stainless said:

I have been looking at diagrams and pictures of the fuel injectors, and I think a third possible route for fuel leaking into the camshaft/rocker area may be possible: Diesel fuel under full (running) injection pressure may escape up through the injector stem/pushrod body itself and into the camshaft/rocker area.

Unfortunately, I guess the only way to check this out would be to run the engine up without the camshaft/rocker cover in place, a little messy I guess with engine oil splashing everywhere, making spotting small diesel leaks very difficult.

When I tackle the job in the future, I will keep you fully informed.

Click to expand...

This is most unlikely as the excess fuel is "spilled" back into the gallery.
It is VERY hot, hence the fuel cooler.

I suggest that in NO circumstances do you start the engine with the rocker cover off!

CharlesY

Hi CharlesY,

The only reason I mentioned the 3rd possibility of Diesel Fuel contaminating engine oil through the injector body itself, was due to the entry by Td5Alive on the "landrover addict" website.

He had heard of fuel injectors inner seals failing , and allowing pressurised fuel to fire out of the top of the injectors where the plunger and spring are. This seemed feasible to me, especially as this area has to withstand 20,000 psi or more fuel pressure.

I certainly don't relish running the TD5A up with the Cam Cover off, but if I replace all the injector O-Rings and Copper Washers, and fuel is still getting into the engine oil, I can't think of another way of tracing that the leak is either from the top of the injector itself, or through a crack in the cylinder head fuel galleries.

I know this fuel/engine oil contamination problem is certainly not the worst TD5 problem to experience, but it seems to be very hard to actually find where the contamination/leak is taking place.

As usual, thanks very much for your thoughts and advice. From other Land Rover website forum blogs of the same problem, I think it is far more common than I first thought.

There's a long thread with reports on the subject on the german forum blacklandy.de, maybe you would be interested to read.
Since most people here are not so comfortable with german language, here's the link via babelfish translation: Td5 - Diesel in the oil
This topic is in the Defender section but it doesn't matter, it's the same thing.

Personally, if I suspected an injector leaking, I'd take all 5 to a fuel injection specialist and get them to check them, lot safer and cleaner than running with the cover off.

Rob

Hi cipx2,

Thanks for the German Land Rover link, very interesting, it seems Diesel Fuel into Engine Oil contamination is far more widespread than I first thought.

As far as I understand them, some German TD5s only needed new O-Rings (and Copper Washers) on the fuel injectors, while others needed new cylinder heads. Land Rover do not seem very keen to accept liability on this, perhaps legal action is the only way forward.

I am fitting new O-Rings and Copper Washers to my TD5A Fuel Injectors, and I hope they will end my fuel contamination problem. If not then a new cylinder head will be required. Not very good on a 2003 vehicle that has only covered 20,000 careful miles.

Thanks again for the link, this really does seem to be serious, involving mainly 2003 onwards face-lift Discos and Defenders. Did the reworking of the cylinder head and the increase of injection pressure from 20,000 to 27,000 psi prove too much for the design.

I notice the diesel fuel pressure regulator has been moved from the back to the rear right side of the cylinder head after 2003, so there have been changes made to the cylinder head fuel rails/drillings. If a new cylinder head is required, would an early pre-2003 design head be better, if still available.

If there are weaknesses in the later head, then a replacement late head will fail as well. Not very re-assuring.

Hi;I too have fuel getting in to the sump oil,and have decided to first try and change the copper washers and o rings.Is this complicated and does anyone know how to do it?Cheers and best wishes from cold wet France.

wardy said:

Hi;I too have fuel getting in to the sump oil,and have decided to first try and change the copper washers and o rings.Is this complicated and does anyone know how to do it?Cheers and best wishes from cold wet France.

Click to expand...

It is a perfectly staightforward job, and the RAVE manual (you have that, yes?) makes it all clear.

If you don't have RAVE, get the download before you tackle the job.

I advise you to read very carefully the details in the thread earlier.

You need to take care not to drop bits down the chain gallery at the front of the engine. Job 1 when the cam-cover comes off is a big clean cloth to block off the chain gallery!

Note especially the bits about crrrross-hatching the copper washers, greasing O-rings, draining the fuel gallery, sucking excess fuel out of piston crowns, and checking copper washer thicknesses. If you are SURE that the new copper washers are NOT thicker than the old ones (check them one by one with a micrometer) you need not adjust the injector rockers. And check torques many times.

RAVE Manual is your next move.

CharlesY

Hi charlesy;Thanks for getting back to me,sourcing a RAVE manual now,have read all the earlier threads with interest,however think it might be cracked head as I drained over 14litres of 'thin' oil from sump,but will try injector seals first.Many thanks.

wardy said:

Hi charlesy;Thanks for getting back to me,sourcing a RAVE manual now,have read all the earlier threads with interest,however think it might be cracked head as I drained over 14litres of 'thin' oil from sump,but will try injector seals first.Many thanks.

Click to expand...

14 litres .... wow .... I hope you tipped it back into the fuel tank.

CharlesY

CharlesY said:

Are you thinking about skimming a TD5 head?
There is absolutely bugger-all clearance available between pistons and valves in these engines, and if you skim the head the valves will be closer to the pistons by whatever you skimmed off.

I recall that this head-skimming practice is expressely ruled OUT by LandRover,

Click to expand...

In case you need to do it:

There are several thicknesses of gasket available, so in theory you could make up the difference with a thicker one. A specialist who is prepared to undertake the job should be able to provide this. You need to check the existing gasket thickness - they are marked with a thickness indicator. The reason LR say don't skim is because the head is specially surface-treated in manufacture. Some members of this forum have had it done with no problems though. Try a search.