Coming soon when I get the pictures to appear...
INTRODUCTION
As I mentioned previously in another thread, I decided to have a go at changing the Haldex oil and clean the filter on TIBET III’s Haldex V unit after reading the threads on Briskoda.
The idea of this guide is simply how I did it, based on advice from others but it maybe, that I did things slightly differently to others or perhaps I had a problem that others haven’t encountered and which someone else might find useful to know about. It is also Yeti-specific.
SERVICE HISTORY
After reading about the pump filter issues on the Haldex V and having lost faith with the MK dealer for various reasons, I decided to do it myself. Experience level – I’ve maintained my cars over the years (I’m an aircraft engineer by trade) but more recently, with the cars being under warranty, I’ve let the dealer do it. I reckon anyone who is competent at basic servicing tasks (oil and filter changes etc) can cope with the Haldex V oil change and filter clean.
JOB PREPARATION
One of my concerns was jacking (safely for me!) the Yeti giving me sufficient room underneath to do the job without struggling for access. I’ve never really trusted the drive on ramp idea so it was going to have to be jacks and axle stands.
To jack the Yeti up, I used the standard car jack on one side and a straight lift mechanical pillar jack on the other (actually a 4.5T Land Rover jack). I prefer to rely on mechanical lifting but had in addition a trolley jack on the jack pad inside and aft of the Yeti jack. The LR jack had the good old slotted ice hockey puck to protect the sill flange.
The axle stands I positioned at the rear suspension attach points just forward of the bumper behind the wheels. They weren’t taking any weight as such but were there in case the world moved from under the jacks. This may not be an ‘approved’ support point but their role was one of protecting me in the worst-case scenario. I also had wood blocks under the wheels which meant I wasn’t going to get squashed even if someone nicked all the jacks and axle stands whilst I was looking the other way… Perhaps this was all a bit OTT but I had the kit, it doesn’t take long to do and you’re a long time dead.
The service kit came from haldexrepairs.co.uk – an excellent and useful website, lots of good info and tips and a good service. The kit was complete including everything from the oil and replacement drain and filler plugs to a pair of gloves. Brilliant.
ON WITH THE JOB
DISCONNECTING THE CONTROLLER
The first thing was to run VCDS to check for any errors but everything was fine. It also warmed the car and everything up. No idea if the Haldex system likes being warmed up but it won’t do any harm!
I knew one of the most ‘difficult’ tasks was accessing the pump harness to enable the pump to be removed. In actual fact it wasn’t too bad but even with a torch and mirror, once again the adult-proof VAG plug on the controller was impossible to undo. Yes, I’ve watched all the ‘how to guides’ but it didn’t push further on, the locking tab wouldn’t budge and the plug stayed fast.
Plan B was to remove the controller from the Haldex unit to allow better access to the plug. This worked a treat. It’s held in place with two 10mm bolts but it still needed a gentle prize to free the controller from the Haldex unit mount after removing the bolts. This meant I could now get to the plug although it didn’t budge until a subtle and careful twist with a large flat blade screwdriver provided just enough force to ease the plug clear.
The other connector plug on the controller has a clip-on 90° cable strain relief cover on it. Removing that enabled more flexibility to access the pump connector plug.
The harness is held into position on the top of the Haldex unit above the drive shaft by two plastic split clips. It was easy to do one from the lefthand side (above where the controller was) and the other from the righthand side. The trick is two squeeze the end of the clip together from the aft side and then push the clips forward and out of the locating holes. The two clips are actually joined together by a length of split plastic.
The workshop manual says to lower the main final drive unit down for access (7 turns) but I’m not sure why you’d need to.
DRAINING THE RESERVOIR & PUMP REMOVAL
Delighted with getting the pump electrically disconnected, I slackened the filler point plug and the drain plug - both are Allen socket head screws (8mm for the drain plug and 5mm for the filler plug). The drain plug must be more than just a drain plug as it’s pretty long and torqued (according to the Yeti workshop manual) to 40 Nm. The filler plug is much smaller and shorter and torqued to 15 Nm. I gave the area around and above the drain and filler points a good clean to prevent any crud getting inside the unit.
With the drain plug removed, the oil drained into the drip tray and removing the filler plug allowed a full flow. I was impressed as the oil looked pretty clean. Perhaps my filter was going to be okay…
DRAINING THE RESERVOIR & PUMP REMOVAL
Delighted with getting the pump electrically disconnected, I slackened the filler point plug and the drain plug - both are Allen socket head screws (8mm for the drain plug and 5mm for the filler plug). The drain plug must be more than just a drain plug as it’s pretty long and torqued (according to the Yeti workshop manual) to 40 Nm. The filler plug is much smaller and shorter and torqued to 15 Nm. I gave the area around and above the drain and filler points a good clean to prevent any crud getting inside the unit.
With the drain plug removed, the oil drained into the drip tray and removing the filler plug allowed a full flow. I was impressed as the oil looked pretty clean. Perhaps my filter was going to be okay…
Whilst the reservoir drained, I set about moving the pump. The first thing to do was to give the pump and the housing a good wipe down to prevent any dust and dirt from unduly contaminating the pump. This was easy with two Torx screws to undo followed by a very gentle tap with a nylon hammer and then a wriggle and out it came, releasing a bit more fluid.
FILTER AND PUMP CLEANING
I couldn’t believe just how blocked up the filter was – and the congealed mess left inside the pump housing on the Haldex unit – exactly as others had found. It’s strange – almost like grease with little substance when you touch it. It didn’t seem to be water/moisture contamination.
The next job was to remove the filter which is held in place by two Torx screws. Then it was a case of gently easing the plastic filter clear. It sits on two locator bushes that also act as spacers and should protect the filer from being crushed when the Torx screws are tightened.
I used warm water and a small paint brush and some washing up liquid to clean the filter and then once rinsed, left it to dry off whilst I cleaned up the pump.
The pump cleaned up easily and I used a small blast of air from my compressor to clean the old fluid out of the ports. It was then a case of replacing the O-rings, removing the old ones carefully with a very small flat blade screw driver being careful not to damage the pump.
Incidentally, there was a couple of patches of light corrosion on the pump (on the mounting flange). This was easily removed with a Scotchbrite pad – don’t use wire-wool as this can cause dissimilar metal corrosion if stands of the wire-wool get embedded in the aluminium pump. I also use lint-free cloths for the cleaning to avoid fluff and stuff getting into the bits where you don’t want fluff.
With the O-rings replaced, I blew air through the filter to ensure it was dry and refitted it to the pump. There seems to be two ports in the pump housing – presumable an inlet and an outlet. I scooped the gunge out being as careful as I could to avoid pushing any of it into the ports.
REFITTING THE PUMP AND FILLING THE RESERVOIR
As with all good Haynes manual advice – installation is the opposite of refitting. Before fitting the pump, I gave the O-rings a good coating in fresh Haldex oil to lubricate them as the pump is refitted. It slipped in a treat and I secured it in place with the two Torx screws. I made sure the harness had the correct routing before I fully pushed the pump home.
Once the pump was properly installed, I locate the right and then left harness clips and then reconnected the pump connector plug to the controller, the 90° harness stain relief cover to the other controller plug and refitted the controller to the mounting points on the Haldex unit.
I used the airline to give a light blast through from the filler point after putting a very small amount of fluid into the reservoir to help flush it through. I had a small syringe to do this with. A big 100 ml syringe (and a length of plastic hose) comes with the service kit from Haldex Repairs for the main filling.
Next job was to fit the new drain screw. The service kit came with new drain screw and filler plug but the original ones could have been reused – there was nothing obviously wrong with them. The new ones obviously have new sealing washers on them. As mentioned, the drain screw is torqued to 40 Nm according to the workshop manual.
With everything secure, the next task is to refill the reservoir. The big 100 ml syringe with the service kit works a trat with a plastic hose that just fits in the filler point. I found you had to be careful not to block the filler point completely and that made it pretty much airtight and difficult to operate the syringe. The reservoir took most of the fluid and some started to over flow out so I refitted the filler plug.
FINAL CHECK AND VCDS ERROR CHECK AND PUMP RECALIBRATION
Next job was to check everything was clear and I lowered the Yeti pretty much to being off the jacks. I started the engine and let it run for 5 minutes. I then used VCDS to run the ‘learn pump’ program as suggested by Haldex Repairs. You could clearly hear the pump running through a specific cycle. The tone changed as the pump filled up.
A quick jack up again enabled another oil level check of the Haldex reservoir. What I had initially thought to be fluid flowing showing the reservoir was full but with a more concerted effort on the syringe, I found I got a fair bit more into the reservoir and when it was really full it really did flow out! Unfortunately, I forgot to get a picture of the refilling but that’s a pretty simple job – just be careful not to put too much effort into operating the syringe and end up blowing the plastic pipe off. I used probably 800 ml of the 850 ml supplied in the bottle.
Although the car was jacked up at the back, it probably wasn’t that much of an angle so I think the reservoir is pretty good on the level. Another good look round was done as a final leak and security check. I then ran the engine and again went through the VCDS error code check and ‘learn pump’ program. All appears good.
I am at a loss as to how the system worked with about 80% of the filter blocked – perhaps it wasn’t. I haven’t been in any snow for three years now. Anyway, job done and as others have said – it is a job that has got to be done. If you’re not up to it then it shouldn’t be too costly to get a garage or dealer to do it – you’d just better point the dealers to Briskoda or the Haldex Repairs website to find out how to do it!
Next job will be to take the Yeti out for a road test this weekend. Forecast for snow on Friday….
PS Apologies for the low res pictures, haven't got time this evening to suss why they didn't load - if anyone needs hi res pictures (or a PDF of all of the above) then PM me.