by dapinky » Fri 29.11.2024, 16:01
Doing the job on the bench is the only practical way to do it.
As Mike says, it isn't a job to start at 0900 in the morning if you want to drive out for lunch - and preferably not if you need it for work next week!
Basically, I did mine as part of a series of other jobs, so it is hard to say how much time each process takes on it's own - so I can "estimate" the best approach, but can't guarantee it.....
If your car is complete, and driveable, then I'd suggest running the engine for a few minutes to heat up the exhaust system bolts - it will make it easier to undo them. Then park, disconnect the battery (Hey, okay, I don't bother usually - but the advice is good).
Undo the exhaust pipe from the downpipe from underneath (3 captive bolts). Then undo the downpipe from the turbo. If you have an O2 sensor, you may want to remove it, or if not, unplug the wiring from the car). In theory, the downpipe should now come out..... but there will be various heat shields, bolts and brackets keeping it in place.... just work your way round undoing things as you see them to be in the way. The idea is to remove the downpipe - but you may want to remove it with the turbo as one piece.
Personally, I'd undo the bottom of the downpipe, then remove the exhaust manifold nuts (and the studs!) from the head..... the idea being to lift the manifold, turbo, downpipe out as a single assembly ..... there will be lots of stuff attached or in the way, but nothing that you can't see and get to - ie, no nasty surprises!
With this assembly on the bench, I'd suggest checking the Turbo bearings - any longitudinal/lateral movement means it could be worth a rebuild (at home, it can cost you about £30 for the bearing/seal parts, and doesn't take too long..... if the wear is too bad, it may need to go to a specialist for a full rebuild and any major parts).
The actual wastegate 'hole' can be got at when it's all stripped down, and should be ~16mm as standard. You need to open it out to 20-21mm. Do not go any bigger as it will risk not shutting correctly, and you'll never get full boost. I sue a 20mm ball grinder and take it slowly, allowing the metal to rest if it all gets too hot. It took me about 30 minutes to do the actual 'cutting', but I'm sure that a proper machine shop could do it in less than 10 minutes.
Then "simply" reverse the procedure to put it back together - make sure the wastegate operates freely and the rod works in a straight line and doesn't twist in action.... also that the activator diaphragm isn't damaged. A length of vacuum hose on the fitting, will allow you to test it with a bike pump, car foot pump, or a strongish set of lungs!
Dave
Just the one now, but this one's mine! - and it will be finished eventually..... - but also temporary custodian of a project until it is finished enough for Angie to drive it
...oh, and a 2006 Freelander destined for the jungles of The Gambia - 4500 miles across roads, desert and tracks - what could possibly go wrong?
)
