Most liked posts in thread: 2004 R53 (re)Build Thread

Update:

The car has been given a thorough once-over by my mechanic at my request. Lots of good news and direction on what to do next:

• Most happily, he checked everything I did, and all connections are solid and correct and completely buttoned up. Gave me an A+ and I can’t explain how relieved that makes me feel.
  
• There is a vacuum leak causing a lean mixture that’s so minor it only triggers a lean code once in awhile, not all the time. Their smoke test found nothing. The only weak point is the broken bolt on the throttle body going into the intake tube.
  
• They can’t drill out the bolt because it would ruin the brass fitting that it screws into, which is set into the plastic intake duct.
  
• I’ve ordered a new intake duct, to arrive next week. I’ll put it in next weekend but in the meantime we all feel good about driving it safely.
  
• Weird anomaly they can’t explain (don’t know how to feel about this): they don’t understand the low-ish idle. Their compression test read a shockingly low 60psi on all four cylinders. He said those numbers make them think it shouldn’t even start but that it starts perfectly, runs perfectly, and there are zero issues elsewhere besides the throttle body.

I don’t know what to think about the compression. I still have a few things to do this weekend - I’m draining the cheap oil, installing the replacement drain valve in the oil filter housing, and putting on a slightly shorter belt on Detroit Tuned’s recommendation. But I doubt any of that has any effect on compression.

anyway, this weekend will be filter drain valve and new oil. Belt if I can do it without pulling the bumper. If I need to pull the bumper for the belt I’ll wait and do that next weekend since I know I’ll do front end service mode to change out the intake duct.

so close!

 

I’m so close.

Swapped the camshaft and rocker today. Original cam was toast. Extremely worn low spot on cylinder 2 intake lobe and same beginning to get bad on 3 and 4.

car starts and idles smooth. No misfire codes! Should be done but... I think I messed up the timing in this process. I have p0341 for a camshaft sensor error. Highly doubt the sensor is bad, seems that error will show when the timing is off.

Pretty sure I know how I messed up. I tried to guess at the spot the new cam would align to the sprocket but was off just a little. I thought it was okay to turn the crank to line it up since it was close. But that is probably wrong. I know the crank shouldn’t turn until it’s all aligned properly. So I’ll get into it all over again and re do the timing. I wish I was better at this stuff but I guess I’m learning a lot at every fumbling step I’ve taken.

 

Day 2
My goal today was to get the cylinder head out. I want to drop it off at the machine shop tomorrow so he can have it all week if necessary (expected lead time about three days, but might depend on if we need to replace any parts with the valves and springs etc). After about 10 hours of hard work, the head is out! Among other things. Today we accomplished:

• new oil pan gasket and oil pan re-installed
• pulled the exhaust manifold free from the block
• removed the oil filter housing and replaced its gasket; re-installed the filter housing
• removed the DME and the airbox, along with the air intake tubes
• drained coolant
• removed the fuel rail
• removed the valve cover
• pulled the camshaft pulley and freed the timing chain
• removed the chain tensioner and chain guides
• finally removed the cylinder head!

Not much of a list for 10 hours, is it? It is so much work to get through everything to finally get to the head. And I really took my time with the oil pan and filter housing, I've never done those before. Just finding the damn bolts for the filter housing was probably 45 minutes! ModMini's video on YouTube is my savior. I had that up all day long, play a few seconds, pause it, do the work, go back. I'd switch between that video and the Bentley manual to be sure I was catching everything.

Oil filter housing, old gasket. It has about 42,000 miles on it. I'm not sure of the lifespan for these, but that seems not so old. But there was oil seeping out at the bolts, so this was at least one source of the constant leaks.

Rockers. They look awesome. Everything here appears to be in fantastic shape, no grooves or marking on the camshaft or the brackets. The brackets popped right off with my hands very easily, as I believe they are supposed to.

Found a broken bolt in my throttle body housing. At the top of the photo. I did that last May, apparently. That's the last time the throttle body was out and back in. Dang. I've never had to resolve to broken-off bolt in a housing like this, I don't even know where to start with getting it out. Maybe possible to get pliers on the little bit sticking out to back it out? Haven't tried yet.

The main event! The valves do not look so good. Although I'm not exactly an expert. Looking at cylinder 2 (this is oriented 1 through 4 from left to right in the photo), I can tell it is burned. Thing is, cylinder 1 looks about the same, 3 isn't much cleaner, and 4 does appear to be cleaner but not great. Although I'd imagine there is going to be a lot of this dark build-up after 152,000 miles regardless of a major problem. At any rate, I can't wait to see this after the machining and valve job.

The block and cylinders. I have shop towels stuffed into cylinders 1 and 2 to sop up the mess you see in cylinders 3 and 4. There was coolant pooled on top of each cylinder. That had to have come from lifting out the head, right? It would be all chocolate-milky if it was actually mixing up in there, correct? Bigger question: Do the tops of the cylinders look okay or normal? There is a a lot of built-up grime and crust on them, and I don't know if that is to be expected or not. Either way - should I try to get those clean, and if so, what are the preferred methods or materials?

Two days of work, all organized and waiting to go back in.


I'm sore and exhausted but pretty satisfied with the first weekend. I doubt I'll get into much if any of it during the week this week, but I'll share updates about the valve job progress if there's anything noteworthy. Other than that, I'll be back next weekend, hopefully with a clean and fresh cylinder head to re-install. But first, I'll be getting into replacing the timing chain, tensioner and guides, and the crankshaft and supercharger pulleys. And tensioner. And idler. Miles to go here.

 

luckily I never have had low oil pressure warnings, I believe this happened during this work for the first time. Amazingly, and ironically about at the exact same time you replied last night, I found out what the part is. It's the drain block valve for the oil filter housing. Used to be you had to replace the entire housing when those broke, but now OutMotoring sells a 3D-printed replacement part for $30. It's on the way. You're correct that it would cause constant low oil pressure warnings if I put it back together without the drain valve.

 

https://www.outmotoring.com/MINI-Cooper-R50-R52-R53-oil-filter-housing-drain-plunger-spring-repair-kit-rep_12345.html

I found this by stumbling on to an article at MiniMania about the oil filter housing, I didn't know what I was looking for but I figured I'd start there. Their article showed a picture of the inside of the filter housing and I realized what the part was, and they had it labeled so I knew what to look for after that. Found forum posts from several years ago from a guy who started 3D printing them because people were trying, with mixed results, to replace these with whatever was available at parts stores. They seem to be close but not quite. Then that guy got his 3D printed part into OutMotoring, I went there and sure enough, 30 bucks and I'm set.

 

I'm going to attempt to do this closer to the right way, maybe, and try to tap and die new threads for the correct M6 bolt. We'll see. Not a lot of metal to work with there, but with the thing out of the car and on the bench, I can actually work with it.

I told my wife this morning that is yet another example of the lesson I've been taught before yet continue to refuse to learn... just don't try to find the easy way out when the actual solution appears to be a little bit more difficult than I'd like. I'm stuck at this step simply because I didn't want to take the intake duct out because I remembered how hard it was put back in. If I'd just taken it out weeks ago when I did the first disassembly, I might have tried to drill it out. Live and learn, nothing to beat myself up about, just more valuable experience for the next time. And there will be a next time! If not the Mini, some other car will hopefully benefit from me knowing a little bit more than I did this time around.

 

I've ordered a test kit from Blackstone Laboratories. I'll transfer the drained oil into a clean container so I can check it out when the kit arrives, should be one to two weeks according to their site. Meanwhile, I'll carry on... need to fight through the morning-after sore shoulders and back!

 

great advice, thanks - pretty much describes what I planned on doing.

Got the head back yesterday, it is beeeeyooooteeeeful... shame to put it back in and hide it!

I had the same thought as you re: the broken bolt on the throttle body, that was a likely cause of this whole situation. I broke that (unknowingly) when I reassembled everything last May. It seems plausible that it's been causing it to run lean ever since. That relatively short amount of time might also explain why the guy that did the valve job said yes, the valve is slightly burned, but really not bad. The bigger valve issue was that they were out of round and he corrected that. Besides that he said everything was in really good shape.

Back to work on everything tomorrow. Pulleys, timing chain and reinstalling the head, hopefully all done on Sunday and we start it back up by the end of the weekend.

 

Day 4

Major progress, but not done yet!

• Cylinder head back in
• Exhaust and intake manifold reconnected
• Camshaft and rocker arms back in
• Cam sprocket in place and new chain hooked up, aligned and timed
• New chain guides in
• New chain tensioner in
• Timing case cover back on

Somehow, that's it... the exhaust manifold screwed me so bad today. Embarrassingly, I wrestled with that thing for about two hours. I know that sounds ridiculous. Just could not get it to line up. I still have the engine on the jack and I kept raising and lowering to try and match it up, eventually I did hit the right height to allow to to line up. Until then I just kept doing the dance of getting one bolt in, then the gasket would slip, I'd get that back, but I could never get a second bolt to line up... I don't ever want to do that again. That part of the engine was designed by goblins.

I tried but failed to drill out the broken throttle body bolt. I've put the throttle body back in with the three good bolts, and I'll get it to my mechanic for that one thing, let them use the right tools to do it. My big drill is too big to get a straight shot at the bolt past that air supply horn, and my small drill isn't powerful enough to get the bit into the bolt. Once up and running that's the first thing I'll do. And I may ask them to do a smoke test and a compression test just to be certain I've buttoned everything up properly anyway.

I'm taking a day off work tomorrow to hopefully finish this up. I won't have my oil filter housing drain valve by tomorrow, but if I get everything else done I'll probably go ahead and start it up to make sure the timing is correct and to check for leaks. I guess I'll have to expect a low oil pressure warning if I do that. Tomorrow will be the new pulleys going on, new lower engine mount and then putting all the bits and pieces back into place, reconnecting the fuel rail and plugs and vacuum lines, etc. Hoping to turn it over and see what happens at some point tomorrow.

 

Those are good ideas... I called Detroit Tuned this morning. He didn't straight-up say that the pulleys require the ECU reset but he thinks it might help. I get where he's coming from on not committing to that as the answer, because who knows, I could have a vacuum leak somewhere in all my re-assembly that's causing the wonky idle as well. But the logic behind clearing the adaptations makes perfect sense to me. The computer is governing the engine based on physically-different criteria than it has to deal with now.

I'll work on the adaptations today/tonight and report back. Still think the throttle body maybe has something to do with it, but it seems it would have idled like this before if all it took was that one small weakness from the broken bolt. Either way, I'll get that resolved asap.

 

Cleared adaptations yesterday and that did stabilize the idle a bit, it’s smoother and improved.

I now have a code for lean mixture (p0171) which is new. The car is going to my mechanic today to sort out the throttle body bolt and to do a smoke test, so I should finally know for sure, but it seems like i have a vacuum leak somewhere.

 

Suddenly I’ve forgotten all about leaks... the car is staging a mutiny. It runs worse than it ever did before doing all this. The code for cylinder 2 misfire is back, and it most definitely runs like it has a misfire this time. Never really did before except for the occasional rough stumble at idle. But it’s pretty much terrible now.

My son drove it yesterday, the day after the mechanic checked it all out, and parked it last night with it feeling good and normal, better than before. This morning it has a misfire, I change the oil and it’s even worse.

I’m kinda beside myself at this point. Parking it for the night and stepping away. The only sort of glimmer of hope I have is that replacing the intake tube where the throttle body bolt is broken off will work some magic. That part arrives this week, I’ll install it next weekend. Maybe, to follow the logic of a recent response here, everything is so well cleaned up and balanced and tightened now that that one weakness is really a huge problem. I don’t think I fully believe that one point of weakness is enough to throw everything off like this, to the point of a misfire, but that will be my Hail Mary.

 

I've decided to not go after every single little thing (re: swapping pulleys) and just focus on what I know is wrong - throttle body intake tube. I will also have a good look at my fuel rail and be certain the injectors are seated properly, but that thing seemed basically idiot proof with how easy it was to fit, and the two mounting bolts take care of the rest.

I am seriously thinking about cutting my losses on the undampened crank pulley and buying the PRW crank pulley. I remember seeing something about the ATI pulley - it has to be serviced or rebuilt throughout its life? Is that true? I don't want to get into that much attention and maintenance at that price point. The PRW seems like the perfect middle ground. Honestly, I bought the one I have based on cost. I didn't understand what I was getting into with undampened vs dampened. So to my point about maintenance and attention, living with the undampened pulley would probably be okay if I had plans to tear down and rebuild things frequently, like with a track car. Which this is not.