There is a great walkthrough for walnut blasting by "e90man" out there. It has excellent step by step instructions. A few things to add.
1: drilling out the fittings only with a 7/16" bit WILL make them work with the BMW tool.
2: If on a budget, only purchase the "optional" bent wand, Abrasive Blasting Wand for Mini (90° Bend)* - Part# 81 29 2 208 032. You can reach all the valves with both tools but the last cylinder is very tough, lots of things in the way. The bent tool is still tough to do a good job on that cylinder, but if you have to buy just one, it'll work on all cylinders.
3: 25 lbs of walnut shells via harbor freight is enough to do a ton of cars. Probably used less than 3 lbs.
4: The one bolt on the intake manifold/block (forward most) was binding and stripped. If this happens don't panic, just be patient, hit it with a liquid penetrant and above all, when removing, apply steady smooth torque for as long a turn as you can. I finally got it out, ran a tap through the threads, bought a new bolt, blew out the hole with compressed air and moved on, no drama. I put the new bolt in with anti-sieze.
5: Maneuvering the intake manifold back in is a lot worse than taking it out. It may be worth making some notes when you remove it as to your sequence.
6: Fastest way for my 80k mileage valves to get cleaned was to make sure they were closed, scrape off the giant parts with a screwdriver that I designed specifically for the application (i.e. bent the tip with pliers), vacuum out parts, THEN abrasive blast for about 60 seconds, then vacuum out extra leftover walnuts. I had to repeat this process for a few valves. Mine were nasty.
7: Thinking you're going to do 2 cars in one day the first time you do this is somewhat optimistic.
8: It's a good time to replace vacuum lines (at least some of them) while all this stuff is going out. Especially the lines that go behind your oil filter, mine were extremely brittle.
9: An ecu reset is not necessary but useful when firing the car back up.
10: We had access to limited electrical outlets, and didn't want to trip a breaker, so we pumped up the air tank to 125 lbs and ran it until about 75. No issues at 125 psi.
11: I didn't take pictures but my valves were plain gross. Very very thick tar like build up, the car is much happier now. 80k on the odometer and I doubt it was done (I got the car at 50k).
12: This is really a 2 person job. Yes, 1 person can do it, but it's so much nicer to tag team the problems. This is especially useful to ensuring valves are closed.
13: If any of you guys are in the phoenix area and need help with this, or just want to borrow some of the blasting specific tools, let me know. I have everything to do it except the air compressor (my bud borrowed that for our project). I'm sure second time around it'll be easier -his car is next. I'm not so much looking to do this for cash, but rather thinking that if a few of us got together to help each other with stuff that is not overtly complicated and the dealers are ridiculous about, it'd be cool to have a few guys helping each other. The local dealer charges $1200 for this, and that's just plain stupid.
1: drilling out the fittings only with a 7/16" bit WILL make them work with the BMW tool.
2: If on a budget, only purchase the "optional" bent wand, Abrasive Blasting Wand for Mini (90° Bend)* - Part# 81 29 2 208 032. You can reach all the valves with both tools but the last cylinder is very tough, lots of things in the way. The bent tool is still tough to do a good job on that cylinder, but if you have to buy just one, it'll work on all cylinders.
3: 25 lbs of walnut shells via harbor freight is enough to do a ton of cars. Probably used less than 3 lbs.
4: The one bolt on the intake manifold/block (forward most) was binding and stripped. If this happens don't panic, just be patient, hit it with a liquid penetrant and above all, when removing, apply steady smooth torque for as long a turn as you can. I finally got it out, ran a tap through the threads, bought a new bolt, blew out the hole with compressed air and moved on, no drama. I put the new bolt in with anti-sieze.
5: Maneuvering the intake manifold back in is a lot worse than taking it out. It may be worth making some notes when you remove it as to your sequence.
6: Fastest way for my 80k mileage valves to get cleaned was to make sure they were closed, scrape off the giant parts with a screwdriver that I designed specifically for the application (i.e. bent the tip with pliers), vacuum out parts, THEN abrasive blast for about 60 seconds, then vacuum out extra leftover walnuts. I had to repeat this process for a few valves. Mine were nasty.
7: Thinking you're going to do 2 cars in one day the first time you do this is somewhat optimistic.
8: It's a good time to replace vacuum lines (at least some of them) while all this stuff is going out. Especially the lines that go behind your oil filter, mine were extremely brittle.
9: An ecu reset is not necessary but useful when firing the car back up.
10: We had access to limited electrical outlets, and didn't want to trip a breaker, so we pumped up the air tank to 125 lbs and ran it until about 75. No issues at 125 psi.
11: I didn't take pictures but my valves were plain gross. Very very thick tar like build up, the car is much happier now. 80k on the odometer and I doubt it was done (I got the car at 50k).
12: This is really a 2 person job. Yes, 1 person can do it, but it's so much nicer to tag team the problems. This is especially useful to ensuring valves are closed.
13: If any of you guys are in the phoenix area and need help with this, or just want to borrow some of the blasting specific tools, let me know. I have everything to do it except the air compressor (my bud borrowed that for our project). I'm sure second time around it'll be easier -his car is next. I'm not so much looking to do this for cash, but rather thinking that if a few of us got together to help each other with stuff that is not overtly complicated and the dealers are ridiculous about, it'd be cool to have a few guys helping each other. The local dealer charges $1200 for this, and that's just plain stupid.