DaveSIIA

Oops, sorry

The linkage may resonate equally either side of the static position (in terms of displacement response), but that might not be the primary cause of the "surge" effect. Looking at the structure of the linkage; the out of line forces; boundary conditions presented by the diaphragm unit and the vane actuator, suggests a non-linear element in a feedback loop. Your graph of boost pressure vs rpm shows that the "surge" occurs in the transition region from rising boost with rpm to constant boost. In this region, the diaphragm will be moving off the end stop, so the boundary conditions presented to the linkage will change quite markedly. In turn, this will alter the dynamic characteristic of the linkage, so modifying the feedback system. The other matter to consider is what is providing the mechanical stimulus to the linkage. At 2400rpm the rotational frequency is 40Hz and the firing frequency is 80Hz so this would not appear to excite a 2Hz "surge". The firing pulse is an impulse, rather than a sinusoidal motion. An impulse excites a much wider range of frequencies than sinusoid, so it is more likely that the linkage will respond at its natural frequency. I haven't done any analysis to assess the boundary conditions or the response of the linkage. However, my experience suggests that a direct, linear system would enhance control of the vanes. It might mean clocking the compressor housing and remounting the diaphragm capsule, but the effort would eliminate many of the unknowns in the control mechanism.

You could try Maplin for electrically conductive silver paint. Finding the break is quite simple with a DMM - check there is 12V across the HRW lead connections. Ground one lead on the DMM and use the other to measure the voltage at the middle of one of the broken strips. 12V indicates the break is between the probe and ground; 0V the other side. Move the probe halfway between the first point and 12V/0V, retest. Repeat the probing, halving the distance up/down, until the break is found.

Bit of an off the wall thought - is there a possibility that the vanes are being driven by the dynamic response of the linkage from the actuator? Any mechanical resonance of the linkage could cause the vanes to move and hence alter the turbo characteristic.

Can't comment on which engine will give the higher mileage (service life). My experience is that the 300Tdi is better laid out for working on: Engine further forward in the engine bay Single serpentine belt for all ancillaries, with auto tensioner Water pump & 'P' gasket readily accessible Timing belt change can be done in ~90 minutes, without having to drain the cooling system Otherwise, the engines are pretty similar.

Did the conversion on my 110 at the beginning of May 2008. Thread on LR4x4 has write up. It has been used it extensively for laning in the Peaks, Lakes and N Wales without problem. Driving on snow/ice is far more pleasurable than with the LT230. I don't miss the diff lock, and enjoy the longer legs for motorway cruising. Now done 15K miles and wondering why I didn't do it sooner.

The bolts can be either M12 or 1/2 inch UNF. Make sure to use high tensile bolts with either double nuts on each (to lock) or nylok nuts.

It looks like a standard 5 tonne NATO pintle. A simple check would be to fit the jaw to the towing eye on the Sankey before bolting the pintle to the back of your LR.

I see the primary application of a MS type system with current fully electronic controlled diesel engines such as BMW 3.0; Td5; TdCi; TDV6/Jag; TDV8 etc where fitment to an older Defender / RRC could be problematic due to the ECU and what it expects to communicate with (the Td5 seems to be reasonably well understood as evidenced by fitments to older vehicles reported on this forum). Also, diesel ECU's are 'closed architecture' to those of us tinkering in garages and lock ups. Another plus would be the ability to talk to/control other functions i.e. the transmission controller for a more modern or stronger gearbox; a VGT in place of a conventional wastegate turbo; etc. As I understand it, the issue with MS controlling a diesel is not just about sequencing - that is already handled for the sparks on a PI system. DI requires both timing for the start of injection (relative to TDC) and a duration (to determine the quantity of fuel injected) whereas electronic ignition requires timing and will run with a fixed dwell angle. Injection timing within the cycle isn't too critical on a PI system, hence bank firing of injectors is acceptable. Consider a 4 stroke diesel running at 5000rpm. The combustion cycle is of ~6mS duration. 8 bit resolution for control of the duration of injection would require a dynamic timing accuracy of ~20uS (and possibly considerably less). To achieve this might require a different design controller as it would be asking a lot of MS to do both timing and duration calcs for DI. BTW: It may be of academic interest to try to take a 300Tdi to a higher spec, but there are other more advanced engines on the market to play with. A halfway house might be to use a Bosch VR pump instead of the VE and use a simple controller

I had the same problem when I fitted 265/75 tyres on Freestyle alloys to my Td5 110.The tyres lightly rubbed the spring seats on either side when the suspension was flexed a reasonable amount. The 110 has larger diameter spring seats than the 90 (for larger diameter coil springs), so less clearance. This might be why LR offered 265/75 on the 90 only. The Freestyles had 33.0mm offset (don't know the figure for the Boost alloys, but it is normally cast in with the wheel code), so you probably need rims that give a wider offset. It is worth checking that the axle is centred on the chassis by measuring the clearance each side.

2/300Tdi starter is a direct fit in place of the 2.5NAD starter. It should crank the NAD much easier than the original unit.

Several other thoughts before condeming the power steering box: What tyres are you running, and at what pressures? Are any of the suspension bushes worn/damaged such that the suspension becomes a bit twitchy at speed? Could the pressure relief valve in the power steering pump have stuck closed, giving too high a pressure at the steering box and hence more assistance than required?

Probably brush/regulator assembly. IIRC £10-15. Can be replaced with the alternator in situ. Should add that the screws through the pack require a M5.5 socket to undo.

Sorry for the poor quality scan - the instructions were printed on the bottom of the cardboard box. My kit was bought a few years back, but the wiring colours / functions are the same as the current actuators (I bought a replacement actuator a few weeks back). Pull the white or brown wire to ground for remote operation i.e. alarm. Can't remember which does lock / unlock. Maplin_Central_Locking_YD77.pdf

I can dig out the instructions from mine and scan later.

Or refit the nuts so the drum can't come off.

A 1000 piece jigsaw featuring several Series I's and an Airfix Shaun the Sheep LR kit.

You can also get a throttle dependent squeal from a blowing gasket on the exhaust manifold. Could be manifold to head or maifold to turbo. Tell tale signs would be carbon deposits where there shouldn't be any. Fix the other exhaust problem first and then track this one.

I can confirm it's a straight swap as I fitted one in place of the LT230 on my 300Tdi 110. High/Low linkage coupled up no problem. Only other part I had to change was the front propshaft as the BW one is 2" longer. Box was changed 8 months ago and my only regret is not having done it sooner. On road handling was more sure footed through corners. Off road, it's one less thing to think about - it just works. On snow and ice the vehicle handles the same as with an open diff until extra traction is called for. I tested the traction recently on compacted snow by parking faced up hill with the rear wheels on snow and the front on clear, dry tarmac. Dumping the clutch in first left two small prints in the snow where slack in the driveline had taken up and then clear tyre prints with no sign of wheel spin as the vehicle moved forwards.

Have a look on Green Oval. All you need is under the Downloads section - Rave CD 3.

If the Exmoor Trim stuff is a bit spendy at the moment, have you considered retrimming a pair of standard seats? I recently replaced the foams (bits came from Exmoor) in the seats of my '94 300Tdi. It was an easy job to do. The looks of the seats were greatly improved by spending a morning with an upholstery cleaner, getting ~295K miles of grime out of the fabric. The end result is back to the standard of when I bought the vehicle with <20K on the clock! Money and time well spent.

There are a couple on everyone's favourite auction site. Alternatively, have you tried speaking with Vehicle Wiring Products?

Given the simplicity of the Tdi engine loom, would it not be easy to pick up the complete assembly from a 300Tdi breaker and do a swap? Probably quicker than making a good job of crimping pins on wires and correctly assembling the plug.

You should be able to do a simple check for alignment using the following points as references. The front end of the crank should be centred on the cranking handle hole in the front bumper (both vertical and lateral) The PTO cover on the back of the LT230 should be centred in the hole in the crossmember directly behind the gearbox. IIRC, there should be 25-30mm clearance between the bottom of the flywheel housing and the crossmember. The engine and gearbox should sit pretty well level in the chassis. It might be worth trying to borrow / acquire cheap a 300Tdi Defender gearbox crossmember and associated mounts. The feet for the rubbers are part of the crossmember, so you could kill a couple of birds with one stone in getting the alignment right.

Having followed the other threads on the Garrett VNT, I found that an excellent link with some good detail information. Thanks. I particularly like the note about using vacuum produced when lifting off the throttle during gear changes to actuate the vanes and prevent them carboning up / seizing. There's further useful information dotted around the rest of the site. Need to get off the fence, and follow Turbocharger's lead, to get something built for my 300Tdi.