535xiT Turbo Project - Ready to Pull the Engine

It's taken me about 3 full days to get to the point where I'm ready to pull the engine. I'll share a few of the observations / problems I've made or encountered. 

Starting with the removal of the exhaust - I was really worried about the state of the exhaust nuts joining the downpipes to the midpipes. These looked like they were frozen and I was dreading this step. 

Downpipe to midpipe hardware - note the rust

I managed to impact off three of the nuts with some effort, and completely rounded the fourth nut. I tip for anyone doing this - particularly a Canadian car which lives in road salt a third of the year - do a really good job of cleaning up the nuts and soaking the hardware in solvent (PB Blaster or equivalent) before trying to removing these. Get on the hardware with a steel brush to try to get the nuts back to original size, the fastener I rounded off was enlarged with rust, and I think I used a socket size larger than I should have.

Rounded exhaust joint nut....

 So - I went through my toolbox looking for a solution for the rounded nut - and found my set of metric 12 point sockets that I bought at a garage sale about 10 years ago for $10... I pounded the 10mm 12 point onto the rounded nut with a ball pein hammer - and then gave it with the impact and managed to get the nut off. That made my day.

This will need to be replaced, along with the studs.

 I then removed the rest of the exhaust. I had some severe corrosion in this brace plate which bridges the bottom of the exhaust / driveshaft tunnel under the rear seats near the rear differential. I also had some massive heat shield corrosion. I've never removed my underbody splash shields for spring cleaning to remove road salt - and I can see why it's recommended practise. This brace and hardware will be replaced.

 Onto removal of the driveshafts. No real difficulty here - put the transmission in neutral using a screwdriver next to the shifter, and removed all the hardware with my 3/8" impact. Front and rear driveshafts dropped out without an issue. Use marking paint to index the location of the driveshafts before removal. It looks like I have a leaking transaxle rear output shaft seal - see photo below - will need to take a closer look at this.

Leaking Transaxle rear output shaft? 

 My rear differential has a leaking input shaft seal - this will be replaced before I put the driveshafts back in. Left and right output seals look okay - I'm going to avoid the rear end with this job and do that in the future.

Rear differential - input shaft leaking

 I then set out to the front drive axles - left and right. You have to detatch the lower control arms to pull out the steering knuckle enough to pull the axles out. You also need a hub mounted tool to push out the axle - I was surprised how much force was required to push the axle out of the hubs. My new favourite tool is this Dewalt 20V 1/2" impact..... Lots of power on all the tough fasteners. I also found that my torsion strut bushings were shot and need to be replaced - could be the source of the front end vibration at speed that I was experiencing - so I've added bushings and ball joints to the list of things to do when I put the car back together.

Pushing out the front drive axles from the hubs. 

Driveline carnage - Front and Rear Driveshafts, Left and Right Axle shafts. 

 In prep for pulling the engine - you have to remove the intake manifold to get access to the rear engine lift point on the block, and to remove all the electrical connections under the intake. My turbos were leaking oil through the charge air tract - here's what I found with the intake manifold removed (no surprise, I already have the kit to do the walnut blasting in the gararge). I'll do the walnut blast with the engine out of the car and on the engine stand.

Number three cylinder intake valves.

 Removing the electrical wiring prior to pulling the engine. I found some forum discussions where guys removed the connections from the ECU compartment, so they would have to disconnect all the discrete connectors on the engine. I tried this - and quickly found that it didn't work. The power leads and the grounds in the engine harness don't terminate with disconnect plugs that are accessible in the ECU compartment - you have to dig and split harnesses in order to actually make a clean disconnect. So I ended up reconnecting the ECU terminals - and went to pulling all the discrete connections on the engine. This wasn't that hard - and I used paper tags to label the connections that might be hard to identify later.

Engine harness disconnected from the engine - lying on top of the right side inner fender. 

 The last thing I did was to make sure all the hydraulic and cooling lines were disconnected and free of the engine - transmission cooler lines, power steering lines - all disconnected and moved out of the way. I've been noting all the O-rings and seals I'll need on reassembly - I'll do another post on that topic later in the week.

N54 engine ready to pull. 

All that's left to do is to remove the bellhousing bolts, and the engine mount bolts. I've already got the torque converter / flex plate bolts removed. Looks like I'll hit this on Thursday.

Sources and Links

I hope you found this post useful. Feel free to ask questions in the comments section below. I answer all questions. If you're interested, you can help support this site by using the following links to Amazon.com in the United States. Turbo parts were supplied by Turner Motorsports. Other parts were supplied by Pelican, BMW Park Avenue in Brossard, and eEuroparts.