Turbo replacement, coolant, ignition, VANOS work
 

My 5 Series wagon just hit 185,000 km (115,000 miles), and I've had an engine light (low boost error) for the past 4,000 km. A trip to the dealer confirmed that I had a worn waste gate bushing, corroborated by the unmistakable waste gate rattle sound on acceleration. I was returning from a camping trip with the kids and I got on the phone with Turner Motorsports and discussed the turbo replacement options - I decided to replace the turbos with new Mitsubishi OEM units - identical to the BMW part but at half the price. I thought about what work I would do while having the front end apart, and I added the following:

1. Walnut blast the intake valves;
2. Replace the radiator, expansion tank, thermostat and upper / lower coolant hoses (due to the damage to the radiator fins behind the grille and age). I've already replaced the coolant pump about 2 years ago;
3. Replace the VANOS (variable valve timing system) solenoids;
4. Replace all the drive train fluids - engine, transmission, transaxles
5. Ignition - plugs and coils
6. Do a good inspection and replace any leaking drive train seals.

Today I got the covers off the engine, removed the plugs and coils, did a compression test, dropped the engine and tranmission fluids, and sampled both for lab analysis.

As I go, I plan to do a short writeup with some photos - here's the first day's writeup here:

https://tcbf62.blogspot.com/2018/09/...placement.html

https://cimg8.ibsrv.net/gimg/5series...0d6295a422.jpg
Engine covers and intake piping removed, ready for compression test.

Compression test results were good, but I had oil in the intake tubing - looks like turbo bearing seals may be worn as well.

Wow, I intend to do some of this in the next while on mine, I'm definitely looking forward to your progress! You're taking on a big job but I'm very excited about it and wish you well.

I will be following your progress to help me make a decision on what to do, my car is still running fine but with 124k miles turbos are bound to fail sooner than later. The decision is to either repair it myself or take it to a mechanic (~$2,000 in labor at minimum)....or sell the car and get a V90 (V90 R-design, not the cross country).

The good thing about replacing the turbos is that you'll have a good car for a good while without any other major issues, so I think it is worth the investment if one plans on keeping the car for a long time.

Job just got a little larger - I have an oil leak at between the engine and transmission, and along the oil pan. Suspect the rear main seal.

Was planning to do the turbos in place. Now it looks easier to pull the engine - this way I can do the rear main, oil pan seals, do the turbos with the engine out of the car. I'm planning on doing a walnut blast of the intake valves - can do that out of the car as well since I have to remove the intake manifold anyway to lift the engine......

Just working on my courage - will be about $600 for the engine lift, stand and lift bar - looking like small change compared to the parts I've purchased.

Will keep you all up to date. I have some spare time now - and investing $6k to get all this done will allow me to get another 80,000 miles out of the car.....

Did the same thing recently, went for turbo replace and DP install. end up with replacing all seals and gaskets + all fluids, walnut blasting + some engine goodies like occ/ CP. (dropped the engine and trans)

I currently am having my entire engine replaced as it seized due to a failed oil pump (no warning) at 107k miles. Turbos were replaced (under warrantee) with vanos, o2 sensors at 79k miles. moving parts over from old engine and replacing seals etc. entire job about 6k. Car is otherwise in new condition and struggled with option of repair or parting out. I just do not have the time or place to have a car sitting in my yard to part out.

Thanks for your input guys - my time on the fence is over - I'll pull the engine, add the front main seal and oil pump to the list.

I recently replaced my turbos too. Though I did it a much tougher way. Now I have some boost leak issues my "rigged" up intercooler connection, will solve by just getting a new intercooler. In the video below I explain why I had such a hard time.

@Phil2045 - thanks for sending me the link to the video - very interesting. Have been watching and reading everything I can get my hands on.

I'm convinced now I'll have to pull the motor - will make everything else easier. I just have to live with the fact that the car will be in the garage for several weeks until the work gets done. Thinking of having the hood and bumper covers repainted since the car will be in the garage for this long...

Have started pulling the front end apart - have the bumper, headlights and reinforcing bar off - just need to pull the AC condenser and radiator and I'll have a big hole to pull the motor through....

Will put up some photos tomorrow night.

How's it going @gman6262?

Progressing well - have everything pretty well removed from in front of the engine - ready to go underneath and do exhaust, driveshafts and axles. No doubt this needed major service - blocked cooling fins on most of the coolers, and huge crud under the inlet of the front turbocharger. I've done a posting with a bunch of photos here:

The Fix-it Blog - Sorting Things Out: BMW 535xiT Turbo Replacement Project - Prep for Pulling the Engine

Here's a few photos:

https://cimg5.ibsrv.net/gimg/5series...c2c95868b0.jpg
Oily crud under the front turbo inlet
https://cimg4.ibsrv.net/gimg/5series...9160da38ec.jpg
Intercooler fins about 30% blocked with crud

https://cimg7.ibsrv.net/gimg/5series...6a5a8f7a7e.jpg
Front bumper and coolers removed - time to move under the car to remove exhaust, axles and driveshafts.

Looks like a good time

Progressing well now - everything is done in preparation to pull the engine - exhaust, driveshafts, front axles removed, electrical out of the way, all cooling and fluid hoses out of the way, intake removed. All that's left are the bellhousing and motor mount bolts - looks like I'll pull the engine on Thursday this week.

I put up a bunch of photos here: The Fix-it Blog - Sorting Things Out: 535xiT Turbo Project - Ready to Pull the Engine

Here's a few of the better photos:

https://cimg3.ibsrv.net/gimg/5series...4814746ddb.jpg
Massive crud in the intake ports - will be walnut blasting.
https://cimg4.ibsrv.net/gimg/5series...1accd14f07.jpg
Dewalt 20V 1/2" impact is your friend when removing the front axles and suspension components.

Looking at the blog details, project keeps on growing on scope...and cost! More nuts, bolts, sensors, coolers etc!

You're not kidding about scope and cost. I've spent the last 4 hours working on my Pelican parts order for all the miscellaneous driveline seals, o-rings, etc.... Will give you all a rundown on fhe final cost when I'm done. Once I'm done - I don't think the resale value of the car will reflect the cost of all the parts and some value for my time - just my feeling right now - will have to hold onto the car for a while to get my money's worth. No worries though - i still love driving this car - I just want my full turbo accelleration back.....

Engine and transmission are out - decided to take them out together and split them on the floor, which worked out pretty well. Pulled off the flywheel quickly - no signs of oil leakage from the rear main crankshaft seal - looks like oil from the rear turbo was making it through the block / bellhousing gap which looked like a rear main seal leak from below. There is massive oil leakage through the pan gasket, definitely needs to be replaced.

https://cimg6.ibsrv.net/gimg/5series...58e3672d11.jpg
Engine and transmission on the hook.
https://cimg7.ibsrv.net/gimg/5series...d83e0f6099.jpg
On the ground.
https://cimg8.ibsrv.net/gimg/5series...3cd997a803.jpg
Flywheel off, inspected the rear main - no leakage. Turbo oil leaks were getting into the bellhousing space.
https://cimg9.ibsrv.net/gimg/5series...54727c7d74.jpg
Big open hole - tried to lift engine with transmission over the steering rack / subframe - but we had to drop the subframe to get the x-drive transfer case over the steering rack.

Got the new head gasket done today, along with new timing chain tensioner and Vanos Solenoids. Got the front and rear main crank seals done 2 days ago. Yesterday was a hit and run to Ottawa to drop off the steering rack and front driveshafts for rebuild at Axle Automotive. I'm finally starting to feel like this is progressing. Next up - install new turbos, valve cover, intake walnut blast and oil pan gasket.....
https://cimg4.ibsrv.net/gimg/5series...b8307c3884.jpg
Block surface clean, ready for head gasket.
https://cimg5.ibsrv.net/gimg/5series...001ec584fc.jpg
Pulled the idrive transfer case rear driveshaft output yoke to find the leak. Turned out to be the O-Ring leaking inside the yoke, just behind the splines. Have the parts from Pelican, ready to install.
https://cimg6.ibsrv.net/gimg/5series...0d6b7f3178.jpg
Front main seal leak - now replaced.
https://cimg0.ibsrv.net/gimg/5series...1a50b4bb80.jpg
Head off the engine, ready for cleanup.

Holy shit! Didn't know you were going that deep into this!? Wow man, props to you.

Any updates? Been a while, I hope things are going well for you.

Yeah - getting pretty close to wrapping this up. Have completed all the engine and transmission related items - front and rear crank seals, oil pan seal, head gasket, valve cover gasket, turbos, transmission input shaft seal and transfer case output shaft seal, front differential seals. Got the engine back in the car about 3 weeks ago - have completed installation of new radiator and AC condenser, all hoses with new seals and electrical. Started up the car last week to test and check for leaks - had a small issue with the VANOS timing wheel alignment which I fixed and now the engine runs with no codes. Now I'm just completing the front bumper - reinforcing bar is installed and I'm into headlights, bumper cover, strut braces and trim. On drivetrain - I dropped the rear differential last night - it was a bit of a mess with all seals leaking and I can see that it was down to about half it's normal oil level. Going to flush it out and replace the seals. Have the rear wheel bearings, parking brake and rotors done - as soon as the diff is back in I'll install the rebuilt CV axles. On the front - still need to do the tension strut bushings, install the front CV axles - then I'll be ready to get it out of the garage. Should be another couple of weeks.....
https://cimg2.ibsrv.net/gimg/5series...a8cb3c5458.jpg
Sandblasted and powdercoated engine subframe. Sent this out to a shop - was a huge amount of rust and it would have taken forever for me to try to clean it up in the garage.
https://cimg3.ibsrv.net/gimg/5series...bddc3684cb.jpg
Head off - cleaned up, ready for head gasket.
https://cimg4.ibsrv.net/gimg/5series...012fd5e36a.jpg
Rear brakes - new bearings, new splash shields (old ones had completely corroded away at the wheel carrier), new parking brake shoes, ready for new rotors.
https://cimg5.ibsrv.net/gimg/5series...57dd0bfefa.jpg
Engine in the car - just completing hoses in preparation for test start.
https://cimg6.ibsrv.net/gimg/5series...4777964c1c.jpg
Engine and transmission going back into the car - straight through the front. Subframe supported by floor jack and axle stands as a backup for the subframe.
https://cimg7.ibsrv.net/gimg/5series...254f602e7b.jpg
Redoing the VANOS timing.
https://cimg8.ibsrv.net/gimg/5series...10fa64073c.jpg
Turbo installation - was a breeze with the engine out of the car - could access all the fasteners and be really careful about all the torque verifications.
https://cimg9.ibsrv.net/gimg/5series...addfd3ce34.jpg
Engine mated to transmission and ready to reinstall. Changed the transmission oil pan, filter and Mechatronic seal with the engine / transmission on sawhorses.
https://cimg0.ibsrv.net/gimg/5series...9ee851cb60.jpg
Rebuilt CV axles and power steering rack - new seals and boots.
https://cimg1.ibsrv.net/gimg/5series...c82fd8463c.jpg
Engine block - cleaned up and ready for new head gasket.

You're doing awesome work. Any updates over the holidays?

I haven't gotten much done over the past 3 weeks - but the rear axles are in, the rear differential flushed and the cover gasket renewed, rear driveshaft in. The rear differential needed all new seals and was quite badly rusted, so i wire cupped it and painted it prior to replacing the seals. Rear brakes are done - new parking brake shoes and hardware, new rotors. Since I had a front drive axles out, I decided to replace the front bearings - those are done now - just working on getting the front axles replaced. When I went to install the right front axle - I found a small oil leak in the oil pan - one of the panel covers underneath the right axle bearing support was weeping. So I've drained the oil, will remove the bearing support (4 bolts) and renew the gasket under that panel. I considered skipping that, but since I'm there - there will never be a better time to do it.... I've also replaced the tension strut bushings - one was blown and leaking fluid.
https://cimg4.ibsrv.net/gimg/5series...4c5167dbc9.jpg
New rear rotors and parking brake shoes / hardware.
https://cimg6.ibsrv.net/gimg/5series...639468a0c8.jpg
Drained and flushed the diff, wire cupped and painted prior to replacing seals.
https://cimg5.ibsrv.net/gimg/5series...94dc747f55.jpg
Pressing in the new front wheel bearings.
https://cimg7.ibsrv.net/gimg/5series...0745d98188.jpg
Replacing the tension strut bushings.

I'm up to about $10k CAD ($7500USD) for everything - turbos, tools, radiator, AC condensor, all four axle rebuilds, steering gear rebuild, wheel bearings, rotors and brakes, bushings, hoses, seals, hardware. I've got a spreadsheet with all the detail - will share when I'm done. It's pretty clear that I'm going to have to drive the car for another 5 years to make this make financial sense - but at least I know I should be in pretty good shape to run this to 300,000 km. I still love the car. All my friends think I'm crazy....

It's running. Finally got the brakes, suspension and wheels back on, finished the cowl over the engine, radiator cover, intercooler support, etc. Took it out today for a short run to warm up the transmission to check the fluid levels. I want to polish the headlights before I replace the front bumper cover, then I'll take it in for a wheel alignment, charge the air conditioning, and torque the axle nuts. I have the heat shields and exhaust to replace, that shouldn't take too much time. Looking forward to getting the back out on the road.
https://cimg7.ibsrv.net/gimg/5series...c844f01f0c.jpg
It's running!!

:notworthy: WOW, what an undertaking! Kudos to you! :notworthy:
It is pretty admirable what you did, enjoy it for years to come!

DANNNNNNNNGGGGGG!!!!! Way to work for what you want. Nicely done. You have a great space to work in, and obviously some solid skillz. ;)

Can't wait to hear how it runs after break-in.

Jose

Guys - I just wanted to thank everyone for their encouragement over the past few months while I've been working on this project. I just got back from the dealer - they did the wheel alignment, torqued the axle nuts at the hubs, charged the air conditioning system and adjusted the parking brake
https://cimg6.ibsrv.net/gimg/5series...e5a1d34411.jpg
The car runs awesome now - it feels a good as when I got it at 78,000 km. The little stumble / hesitation on acceleration is gone now - i credit that to the intake valve cleaning / walnut blasting, and it's awesome to have full boost and torque back - acelleration is awesome. Great to have my car back, I don't have to borrow my wife's Outback anymore. I took a few hundred photos, when I get around to it I'll add a few of the lessons learned along the way, mistakes I made and pitfalls to avoid. Overall, it was a great project, lots of fun.

That is awesome and, again, what an undertaken!! Congratulations and enjoy your car for a lot longer now!!!

Did you replace your turbos or just have the wastegate linkage replaced?

I noticed that the output seals from your passenger side axle carrier and the front diff have the red plastic piece in them to assist in sliding the axle in. My Bentley manual says that new seals will come with these guides and oddly mine did not, even though I bought the seals from my local BMW dealership. I'm assuming it won't be a problem to put the axle in without those, but thought it was interesting to note.

I replaced the turbos with Mitsubishi OEM replacements from Turner Motorsports. They were drop in replacements except for one small wastegate actuator bracket which I needed to swap from the old turbos. They’re running great.

The red plastic bits on the Front diff output seals are not guides - they are too small. I think they just protect the sealing surface and make sure it stays round during installation.

Amazing amount of work there. I’m comfortable with old cars and have replaced the starter on my e61. Inspiring to see you do this at home. Gives me hope that I’ll be able to tackle some of the harder jobs down the road.

Here's a 16 month update on this major repair. The repair has mostly been sucessful - full boost from the turbos, reliable operation. A few problems emerged however - my resealing of the small cover plate on the right hand side of the oil pan (where the front right drive axle passes through the oil pan) ended up leaking worse than before. I also just recently got low boost pressure faults and reduced engine power errors. I've had the car in the garage for a week now, troubleshooting everything and figuring out what's going on. Low boost pressure was caused primarly by a bad vacuum line to the rear turbo wastegate actuator (this was a vacuum line I replace with hose supplied with the turner motorsports Mitsubishi turbo kit - I think the vacuum line was cheap). I'll be replacing all the vacuum lines in the car with silicone hose. I tested the turbo pressure controllers - both were bad and I'm in the process of replacing them now. I also tested both pop-off valves - and the rear one was bad, it's now been replaced.

I just got all my parts yesterday, in the process of putting everything back together now. I did a short writeup on repairing a small leak in one of my transmission oil cooler hose quick disconnects here: https://www.fightchaos.com/2020/08/r...il-cooler.html and a post on the oil pan side cover repair here: https://www.fightchaos.com/2020/09/b...-pan-leak.html. With the right front drive axle removed, and the exhaust system removed, I saw that I had pretty good access to the oxygen sensors and since they haven't been replaced yet at 205,000 km, I've decided to replace them now while everything is apart. That's gone well - fairly easy to remove all four O2 sensors and I have the front 2 sensors back in and torqued down already. Here's a few photos - I'll put in an update when everything is done.

https://cimg1.ibsrv.net/gimg/5series...6f7104d4d0.jpg
Replacing the O-Rings in the Transmission Cooler Hose Quick Connect Fittings.

https://cimg8.ibsrv.net/gimg/5series...98dabaf44e.jpg
Oil pan side cover re-sealing. Tip here is to let the sealant cure for 48 hours before torquing fasteners (not 1 hour as recommended in the sealant instructions)

Shoot, I’m sorry to hear about the recent issues. When you did all this work it inspired me to remove my own turbos and replace front diff seals and whatnot (though not nearly to the extent you did). Mind if I ask how you tested the boost solenoids? It seems like I have read others say they are not particularly easy to test other than putting a gauge on the output side of the solenoid while driving.

Testing the pressure controllers was pretty simple, you can do this in the car. I bought a handheld vacuum pump with gauge, since I was going to be testing all vacuum components on the engine - wastegate actuators, pressure controllers and the pop off valves. To test the pressure controllers, disconnect the two hoses and the electrical connection, apply vacuum to the inlet port (from the vacuum reservoirs) - and the pressure controller should be closed, and allow vacuum to build without releasing it. Both my controllers failed this test - they were leaking vacuum to the outlet port (to the wastegate actuators). I could tell because I could only build vacuum with the pump holding my finger over the outlet port. Second test would be to build vacuum, then slowly let it off by applying quick pulses of 12v to the controller electrical contacts (you can use battery power and test leads) - the pressure controller should allow you to slowly and evenly drop vacuum over several pulses. A bad pressure controller may let off all vacuum with a single pulse of 12v. Third - the pressure controller should be able to hold vacuum even during vibration (you can apply vacuum then tap the end of the controller with a small wrench or screwdriver). My controllers would lose their vacuum with minor tapping - when holding my finger over the outlet.

The handheld vacuum pump is a nice tool - I found that one of my pop-off valves was bad (the rear one) and the vacuum line between the rear pressure controller and turbo actuator was crushed (probably the main reason I was getting the low boost pressure code).

Amazing work and commitment
 

I have deep admiration for what you’ve done and I am sure you’ll be running to 300,000+. I’ve had trouble sorting boost leaks and the crap plastic parts don’t help. I replaced the piping with aftermarket metal and I can (at least) cross that source off the list.

im on to rewriting headlights for the look i want. Never knew I like electrical. Time will tell.

Mind sharing what you have in mind for your lights?