Boydie

If the piston isnt worn or damaged then oil should'nt get into the bottom poppet valve gland which is the discharge into the engine sump..... ergo there shouldnt be any leakage from around the welsh plug, however if there is and then a new welsh plug inserted with a reputable sealant (Rolls Royce Sealant) should cure the problem. Knowing Wabco the size of the welsh plug will be an oddity, but if the end plate is removed then having it honed out to a standard size, say 20mm shouldnt be a problem as I recall there is considerable land around the plug.

You will still need the vac pump to power the brake assist.

If oil is getting into the area of the pop riveted plate then it means oil is getting past the piston, if that is the case then the piston seal is either damaged or worn, in either case replacing the pop rivets with screws or bolts will not resolve the problem, -- replace the pump. I wrote a article on this on WABCO vacuum pumps.

Snow !!!! Try 40 + (degrees centigrade that is) I'll put some photos for you to gaze at on the site when we return.

Interesting, I was thinking of something more "aggressive" - such as a Subura WRX Type STi or the Nissan Patrol to entrain even more air when the vehicle is moving. My thoughts were to cut the bonnet in such as way as to make radial blades to direct the entrained air down onto the manifold. Has anyone tried the idea of "finning" the allow inlet manifold?

Copy that, thank you for taking the trouble anyway, have a great New Year

Thanks Western for this thread but the part numbers I need are the springs, check balls and the restriction washers in the Valve Block, the parts manual you show gives the valve block as a complete item whereas I'll be pulling it apart & rebuilding it, hopefully with either fault free originals or replacement parts. The other thing I'm looking for is a source to obtail the special tools required (and listed in the ZF Manual) to dismantle and reassemble the gearbox

Would you have the VALVE SPRING DATA and RESTRICTOR WASHER SIZES for the Valve Body Assembly for the Defender/Discovery 300TDi version of the ZF4HP22 gearbox? I've aquired a very detailed service manual for the ZF4HP22 issued by Volvo and while ZF )Service) Australia have confirmed that its accurate as far as assembly and dissassembly methods, listing the special tools required etc. the above details listed in the manual are for the 740/760 series of Volvo cars. While I suspect several of the these Valve Body Components will be common to the 300TDi version of gearbox I really need to know so that I can pre-order such things as springs, nylon balls and the restrictor washers so that I can fully overhaul my gearbox. This request is also entered in the Discovery Forum.

Done that and replaced the welsh plug as well at the overhaul, the gasket on the pump was an aftermarket one I could have used for a rolley, it was that thin, I considered making my own out of .8mm gasket cloth and I'm now regretting not doing it, oddly enough the seak (seak = seeping small leak) seems to have self sealed but the gods of Land Rovers and St. Murphey will wait until well in the Flinders Ranges on a mountain track that would give a Moroccan goat a serious case of vertigo and the nose bleeds and then and only then will it give up and leak.

why didnt you use the JCB to just lower the Disco onto the engine+gearbox+handbrake+driveshafts

Has anyone installed a Bonnet Vent/scoop in their bonnet as in from a Nissan, Mitsubishi or a Toyoya (wash my mouth out) and caused air to flow down over the alloy inlet manifold? It strikes me it wouldnt be very hard (once the rubber cover was permanently discarded) to tig weld 9 off 3mm x 15mm high x 350mm long alloy strips onto the raised areas of the inlet manifold. If a scoop in the bonnet then caused air to flow over these "additional cooling fins" installed on the manifold and then down onto the turbo additional cooling would occur. Obviously there would only be a cooling air flow effect if the vehicle was moving at say 60KPH and over. It would certainly assist in the delivery of cooler air into the cylinders and cheaper and easier to do than installing an expensive aftermarket intercooler, which in any case if installed would also benefit from any method of keeping the inlet manifold cooler.

Thanks again "FOZSUG" I should have also mentioned in regard to S/S bolts that when I stripped the coolant pump down I replaced the pressed metal apology for an impellor with a cast one from a Chysler V8 water pump, it was drilled and machined to suit the Disco housing and heat shrunk and then doweled onto the pump shaft. At the same time I fitted S/S Helicoils to all the threads in the alloy castings. I wont have time to change the gasket before we leave on Xmas day so I could well have a challenge on the way -- well we should'nt always do repairs in the luxury of a well appointed garage!

Well this is it, the last snaps of Puffer the Magic Dicso before we leave, freshly washed and loaded with 65 litres of fresh water, 60 in 3 Jerry cans and 5 in a container in the rear. 195 litres of Diesel, 135 in the long range fuel tank and 60 in three jerry cans on the roof rack. 3x3 meter tent, bad stretchers, sleeping bags, table, chairs, stoves, fishing rods, a 30.06 rifle with 60 rounds, a double 12 bore with 120 rounds of various types, a .22 air rifle with 400 rounds and an inflatable 3.5 metre boat complete with 40 Watt electric outboard motor, 2 bottles of 15 year old Balvenie Single malt, 3 bottles of Gordons dry gin, 10 bottles of Schweppes Indian Tonic watera box of H.Upmann Magnon 46 Cuban cigars and of course some more mundane food and vittles to last us a 3 weeks. All up she hit the weigh-bridge scales at a tad under 3600 kilos - up around 600 kilos from her dry weight. I put fresh boots on her earlier this week and I've resisted carrying an additional spare, the Cooper tyres are 12 ply sidewalls which is their weakest point and any normal puncture in the tread I can fix. I wont bore you with further pics but I'll let you know on my return and you can visit my site to view them. Oh' roads , some of you go "green laning" on this trip the first day we travel 1240 Kilometers, 850 on black-top the remainder on unsealed roads that will vary from flat to goat tracks. From White Cliffs to Lake Eyre through the Flinder ranges the distance planned will be around 1800 Kilometers of outback tracks. From Lake Eyre to Birdsville we will be driving through the Greater Simpson and Stoney Deserts - sand and if tis been raining, bogs and deep creek crossings. To winch out in sand you use the spare tyre as a sand anchor. And in the manwhile I'll be visiting farms I've been booked into to reduce their feral animal population, mainly camels, goats, wild pigs, foxes and wild dogs. Talk to you in a month. Happy Christmas and may you have an even better New Year than your best ever

I'd guess that it could be done but you are going to need a hell of an engine lifter and it's going to come out almost vertical even with the radiator removed due to the length of the combined engine+gearbox. Whats wrong with just dropping the R380 ?

Would anyone have the VALVE SPRING DATA and RESTRICTOR WASHER SIZES for the Valve Body Assembly for the Defender/Discovery 300TDi version of the ZF4HP22 gearbox? I've aquired a very detailed service manual for the ZF4HP22 issued by Volvo and while ZF )Service) Australia have confirmed that its accurate as far as assembly and dissassembly methods, listing the special tools required etc. the above details listed in the manual are for the 740/760 series of Volvo cars. While I suspect several of the these Valve Body Components will be common to the 300TDi version of gearbox I really need to know so that I can pre-order such things as springs, nylon balls and the restrictor washers so that I can fully overhaul my gearbox.

Once the tax man realises that we no longer use heating fuel in our house I think they will come and lock me away, heating fuel (industrial diesel) doesnt carry any road tax or state excise -- result instead of paying $1.50 a litre at the bowser its only $0.72 -- the same rate that farmers here in Australia pay with their fuel subsidies. I get 400 litres at each fill, which is the maximum size external heating oil tank permitted and yes I use two strike oil in it as well, around a 1-2% ratio.

I think you're talking about the High-Low range selector lever not the P-R-N-D-3-2-1 gear shift as was first though. If your transfer gear selector (Hi-Lo) is jumping out of gear then I think it's either one of two things, the lever adjustment is out of kilter or the selector arm in the box is worn. The first can be rectified by the removal of the centre console, this involves disassembly of the T selector lever, handbrake, removal of the console itself and then the gear cover under the exposed carpet -- (drill out around 10 3/8" pop rivets) this gives you access to the top of the transfer box and the selector lever adustment. If its the selector arm in the box thats worn you have to drop the transfer box and have it serviced, or pull it apart yourself and rectify the problem. This can be done with the auto box left in position and with the Disco up on 4 strong ramps (you need the extra ground clearance) but its a person I'm not that keen on of a job and one where you need to have a strong mate around to give you a hand as they are heavy bitches to lower -- and to lift back afterwards! Can anyone else give more infomation?

Thanks for that, I'll go and get them from a bolt supplier in the morning, 304 and 316 grade S/S bolts and studs etc. are pasivated but I'll take on board your comments, so I'll try to get them in Unbrako socket head or some such pasivated high tensile.

Sorry about the delay in my answer, the short one is yes, the ZF4HP22 gearbox will fit the Iveco 2.8 given that some minor modifications to the TC drive plate on the Iveco crankshaft that would be required as well as an adaptor plate to match the bell housing to the Iveco motor, that said there isnt any advantage to make the swap worthwhile as the Iveco has only a little more torque and less hp than the 300TDi so I wont bother taking this any further however the idea of using the variable nozzle Garrett turbo setup from the 2.8 does however have some merit as the torque range is so smooth and it pulls so beautifully it has to be a consideration for some future time. For a "mechanical" (non ECU) motor it makes the 300TDi feel positively agricultural

I just noticed a tiny coolant weep on the gasket joint of my cooling pump and as these things have an bad habit of getting worse before too long I'm going to have to pull the pump face off and replace the gasket. My question without notice is this, does anyone have a record of the lengths of the bolts -- I believe there are 7 in total and of various lengths -- and the bolt pitch(s), which I believe is 8mm dia. x 1.25 pitch. The reason I ask is I know from when I re-assembled the engine that the hexangles on the bolts were getting rounded and I'd rather get new stainless ones before I pull it apart. Oh, and the very best seasons wishes to you all and may your new year be better than the last.

A standard DISCOVERY 300TDi Alternator will fit your Defender 300TDi without any alterations and they are rated at 100 amps... Look up Ebay, you should be able to get a new one for arround AUD $300.00 + P&P. Happy Christmas.

well its now december 2011, do you have a kit price yet? and if so whats your delivery time ?

I was reading a thread the other day regarding a method to repair to oil leaks in the front cover of the Wabco Vac pump which the author rectified by replacing the 6 rivets with 5mm bolts & nylock nuts. As my unit was having the same oil leak problem I followed his example and carried out the rectification, oil leak solved, however...................... The WABCO vacuum pump is at best a fairly simple beast (WABCO = Westinghouse American Brake Company) never were ones for high tech products and originated making brake componants for the US railways. In a previous life I worked for a now defunct English Company, Davies & Metcalfe who made a superior product for steam engines, as it was Wabco purchased D&M and both were eventully bought out by a superior technological european railway engineering company, AB Boveri who were/are also into DC traction motors, anyway I digress. The Wabco pump fitted to the 200 & 300 TDi is a simple pump consisting of a strong spring, a shaft which is therefore pressed against a lobe on the cam shaft and a piston fitted inside a cylinder connected to the other end of the plunger shaft, the spring being in the centre as it were. The piston on its "in" stroke -- that is when the spring pushes the plunger towards the flat of the cam the piston travels away from the external valve plate and air is sucked from the brake servo through a simple spring loaded non-return poppet valve, on the "out" stroke, when the lobe on the camshaft pushes the plunger and compresses the spring the piston moves towards the external valve plate and the air is pumped through a second spring loaded poppet valve and into the crank case. This being the case and on investigation and very close scrutiny I noted that a tiny section of the lip of the piston had broken away, this was/had allowed, over a period of time, engine oil to pass past the piston and into the discharge chamber of the pistons cylinder, that is the portion of the cylinder capped by the valve plate that was leaking. No doubt the fact that oil resists compression is one of the reasons for the valve plate leaking as the piston would have been hammering the oil against the valve plate and past the "O" ring. It follows therfore that if the valve plate is leaking oil past the "O" ring then oil is getting past the piston and possibly further into the brake servo and contamination of the rubber diaphragm. The only mechanical thing preventing this is the suction poppet valve and the fact that the oil would be held retained in the cylinder by the suction of the piston. WABCO, ever the boys with an eye for profits (the cost of an interconnecting vacuum hose used on railway carriges would make you faint!) naturally do not sell spares for these pumps and I'd guess that being as reliable as they are there simply isnt enough failures to warrant a Chinese company from tooling up so that only repairs able to be carried out are the replacement of the rivets as per the thread I mentioned and welsh plugs that retain the two poppet valves, but as I said from my observations tha only way for oil to get into the suction chamber of the pump is for the piston to be leaking. For my part I'm on my way to my LR parts dealer to buy a new pump

I should have also added to go to their "Home" page and you will see a photo of a 300TDi Disco install, I put my display in the coin holder though as I use the three switches for fog, driving lights and high level (roof) reversing lights.

From memeory its either 1 or 1.5mm, after I got rid of the ALB system I set mine up using the antilock "cog" on the front passenger side front wheel, I only use it for distance though, not for speed though as my ZF has a transducer but its nice to know that the distances registered are acurate to a meters or so over a couple of hundred.