TD5 Head Gasket & PAS Box Replaced - Job Done! (Long)

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Hedgehog70

Active Member
Posts
161
Location
Leeds
Well after many hours, I have now completed the replacement of the Head Gasket and Power Steering Box on my 1998 Discovery 2 TD5. My vehicle has FSH and has covered 94,200 miles.

In true Land Rover style there were no obvious symptoms of the HG failure until I started to get tiny air bubbles continually from the bleed screw when it was undone slightly. Also on a run water would be expelled via the header tank, but these problems were not present initially and sniff test and pressure tests all proved normal. Similarly there was no oil in the water nor water in the oil.

Firstly, a little bit about me. I am not a mechanic and my ramblings here are purely to assist others who may experience a similar fate. My approach was what I call “Monkey See. Monkey Do”, along with a copy of RAVE, Microcat and with some assistance on the rebuild from my Dad who is a retired mechanic. Having been quoted up to £1000 by independent dealers just to do the HG I went into full Yorkshire mode on two fronts i.e. not only could I do it cheaper, but that I could also do it ‘better’ in so far as I would clean more and replace more.

So, on to the job in hand replace the HG and PAS box (due to bad leak from the output shaft seal). The PAS box is fairly straightforward. I had used some stop leak in the system which had failed miserably so I bought some cheap ATF/PAS fluid to use as a flush and this was a good move and I am sure the pump will thank me for it. RAVE tells you to remove the PAS box from the underneath which would involve removing the Panhard rod, but as I was doing the HG and the radiator and intercooler were removed already I lifted the PAS box upwards which was much easier. It’s still heavy though and must weigh close to 20kgs. Once drained down I removed the reservoir and gave this a thorough clean with brake cleaner. To separate the arm from the steering rod you will need a fork type ball joint splitter as it is tapered. I managed to get a brand new splined intermediate shaft for a mere £20, so I changed that as well. I also replaced the 4 ‘O’ ring seals on the 2 pipes that connect to the PAS Box. The part numbers are as follows: -

• QED100100 – Green Thin
• QED100110 – Green Thick
• QED100120 – Brown Thick
• QED100130 – Brown Thin


I also replaced the M8 x 16 bolt that holds the 2 pipes in place along with new jubilee clips on the reservoir pipes. Bleeding the new box is fairly straight forward as there is a bleed screw on top of the PAS box, so just undo half a turn until all the air is expelled. Mine took 2.5 litres of new PAS fluid and I went for the Genuine Land Rover stuff and about £13.00 a litre. The steering now feels fantastic, so I hope the recon. box gives me no trouble.

Onto the head gasket then and the strip down is quite involved as you would imagine, but just think of it as Meccano and you won’t got too far wrong as long as you LABEL EVERYTHING. I used wraparound labels with sellotape over the top on all pipes stating where it connected. Every nut and bolt I removed (that could not be screwed back in to its original part) was clearly labelled using Post-It notes giving a description and quantity and kept in small oddment trays. Every nut and bolt was thoroughly cleaned and in the case of metric nuts and bolts, replaced.

The parts to be removed include: -

• Acoustic Cover
• Fan shroud
• Front Grille
• Horns
• Indicators
• Radiator & Intercooler
• MAF and hoses
• Top Water Hose
• Heater Hoses
• Turbo Heat Shield (Bracket Was Snapped So Welded Up Nicely)
• Turbo
• Exhaust Manifold Shield
• Exhaust Manifold (soak studs in WD40 twice daily for at least a week)
• Inlet manifold
• Fuel Cooler (release and leave in-situ)
• Fuel Pressure Regulator Block
• Camshaft Cover
• A/C Pump (Unbolt and move to allow access to exhaust manifold studs at front (No need to disconnect refrigerant hoses))
• Viscous Fan
• Auxiliary Belt
• Wiring Loom (Comes through first opening of inlet manifold and bolts to front of head)
• Glow Plugs


So one you have got this little lot off you can lock the timing (mark crankshaft pulley as well – I used nail varnish). Next, undo the head bolts (all 12) and then lift the head off. The easiest way if you don’t have a hoist is for 2 of you to climb into the engine bay and just grab hold. It helps if you remove the rubber across the top of the bulkhead and push the sound deadening down behind the head. You need to lift the head off vertically as far as is technically possible. It weighs about 35kgs I reckon so be careful.
My gasket did not look in good shape at all and the plastic locating dowels were badly distorted. Once the head was off I gave it a really good clean. I noted the injector codes and their position before removing the camshaft and injectors. The head then went off for a pressure test (which after 24 hours was all good) and then a very light skim.

Whilst it was away I prepared a list of parts to be replaced during rebuild. I am planning on keeping ‘Vera’ for a good while so whether you choose to be as extensive is up to you and your budget. One thing to note is that you must only ever put the same head gasket thickness back on as the one you took off. This is because head gasket thickness is relative to piston height and not the depth of the head. So on with my list (Part Numbers Given Where Possible): -

• LLR016319 – Fuel Pressure Regulator Block
• LMSX000010 – Crush Gasket For FPR Block
• LXI100000 – Timing Chain Bolt Washer
• LDI100030 – Front Camshaft Oil Seal
• ERR5369 – Rear Camshaft Oil Seal
• AMR6103 – Fuel Injector Harness
• ERR7070 – Timing Chain Sprocket Bolts
• ERR6768 – Manifold To Turbo Gasket
• ERR7079 – Coolant Elbow From Head
• ERR7032 – Crush Gasket For Coolant Elbow
• ERR6192 – Water Temp. Sensor Washer
• ESR3737 – Exhaust Gasket Turbo To Downpipe
• ERR6066 – Glow Plugs
• PYB100140 – Coolant Rail Drain Plug
• PYF100860 – Coolant Rail Drain Plug Washer
• PBH101980 – Hose Heater To Oil Cooler
• ERR6299 – Oil Filter
• LPX100590 – Rotor Filter
• ADU6847L – Turbo Feed Banjo Washers
• PNT100030 – Turbo Return Gasket
• MYC100230L – Vac Hose Clips
• LVF500040 – Sump Gasket
• LYP101400 – Oil Pump Bolt
• ESR4686 – Fuel Filter
• LRJ100000 – Rotor Filter Drain Pipe Gasket
• TRL100040 – Sump Plug
• Sump Plug Washer
• 2 Hole Head Gasket
• Inlet Manifold Gasket
• Exhaust Manifold Gasket
• Cylinder Head Stretch Bolts
• Steel Head Locating Dowels
• Injector ‘O’ Rings
• Injector Copper Washers
• 10 Litres 5/30 Semi Synth Oil
• 6 Litres OAT Coolant
• 5 Litres Brake Cleaner


As you can see from the above list, I decided to replace the Oil Pump Bolt that lives inside the sump whilst I was waiting for the head to come back – In for a penny in for a quid and all that!! Other jobs I did whilst the head was away included cleaning up the face of the exhaust manifold, getting turbo checked out by local Turbo expert, decoking turbo and cleaning mating faces, thoroughly clean inlet manifold (yuk), clean all electrical contacts with specialist cleaner, Waxoyl areas normally inaccessible, cleaning the block face and fitting the new little hose onto the oil cooler.

Once the head came back the injectors went back in along with the camshaft. You need to make sure the head is almost clinically clean before putting the injectors back in because if the ‘O’ rings do not seal then you will end up with a sump full of diesel. The timing was checked, checked and checked again (valves #7 & #10 open if you are interested). It pays to take photos of critical things like this as you go through the dis-assembly phase – This extends to the auxiliary belt as well.

I put the new head gasket on the block (note the bit that says ‘Top’) along with the steel locating dowels. The cams and lifters were given a good lubing with my oil can and then the head was set back on the block in one smooth operation in the reverse of removal (Cheers Dad!!). The new head bolts were given a small amount of engine oil as lube on the tips before being tightened following the stringent 5-Stage process as specified in RAVE.

It was then just a matter of bolting everything back on and replacing gaskets and seals etc as I went. Once all was back together apart from the cooling system I changed the oil filters added the new oil (I had added 5 litres straight over the camshaft before putting the cover on) and then purged the fuel system as per the manual before firing her up (If the fuel pump does not auto shut off after 3 minutes then check that your sump is not filling up with diesel as this is a good sign that the injectors have not sealed). She sounded lovely and smooth so with no leaks I switched her off and connected all the cooling system back up and bled it – No more air bubbles!!

I can honestly say I enjoyed the experience and have learnt so much about the car that I would recommend it to anyone. You will need patience, time and a good tool kit. Mine is pretty comprehensive and mainly ‘Halfords Professional’ but there are several things you really need -

• E14 Star Socket with ½” drive for head bolts (I only had 3/8” drive)
• Torque Wrenches ½” and 3/8”
• Ratchet Spanners
• Air Compressor
• Good Jack
• Axle Stands
• Hose Clip Driver 6mm & 7mm Flexible
• Little ‘Hook’ tool to remove ‘O’ rings
• Viscous Fan Spanner


I have not worked out my total costs yet, but for the PAS box it was about £200.00 for everything. As far as the Head Gasket / Oil Pump Bolt job goes then I reckon I am somewhere around the £700.00 mark including the head skim and test. It may sound a lot, but I have changed a lot. The Head Gasket Kit was £185.00 from Turner Engineering. The head skim was £100.00. The new FPR was another £100.00

But being a Land Rover the story does not end there. Oh no. After a 15 mile test drive, I came back home to discover that the n/s/f brake calliper had started to bind. So I have just ordered 2 shiny new callipers which I will be fitting later this week.

Landies. Don’t we just love ‘em.

TONY
 
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This is one of my TD5 head dowels that came out when the gasket was done!

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