I guess I should start a thread documenting the rebuild or build of my 2008 R52. Intro thread here, so I don't repeat details of procuring and initial thoughts when I bought the car a few months before the pandemic.
https://www.northamericanmotoring.co...jcw-owner.html

Luckily I managed to procure many parts just after the pandemic started so I could spend a good amount of my time working on the car. That early work included:
- new oil pressure sensor
- new crank position sensor o-ring
- Koni Special Active FSD shocks on all 4 corners
- Powerflex front suspension bushings (control arm bushings were fun to try and press in, but overall not that difficult)
- New inner ball joints
- New raybestos front brake rotors
- New Beck/Arnley front brake pads (tried Hawk HPS, but they squealed too much)
- New upper engine mount (OEM)
- New lower engine mount (OEM)
- oil change
- new PCV valve
- new air filter
- new cabin air filter
- new Falken Azenis 215/45ZR-17's

Now it's time to dive in to the other usual suspects. Let me know if you think I need to add or change something, but here's what I'm planning:
- fuel filter
- Supercharger oil and gaskets
- new water pump (OEM)
- oil pan gasket
- dipstick tube o-ring
- valve cover gasket and spark plug seals
- front main seal
- ATI 2% crankshaft pulley
- new belt tensioner (OEM)
- new idler pulley
- new belt (which one for JCW & ATI 2%?)
- new thermostat (OEM)
- aluminum thermostat housing
- aluminum coolant expansion tank with new cap
- new coolant hoses (silicone - yay or nay?)
- low speed fan resistor kit (likely - still need to test and confirm)
- new power steering hoses (OEM)
- new coil (MSD)
- new plug wires (MSD)
- new plugs (NGK JCW, or 1 step colder than S?)

I'm also figuring to pick up an m7 strut tower brace (to prevent mushrooming and might as well get the brace). I like that the brace can come apart for maintenance.

As well, it seems my rear tires bottom-out and hit the inner fenders over big high speed humps. I'm thinking I could stiffen the rear up a little with a bigger rear sway bar and it might fix that. I'm not racing the car, but it sounds like this is a good improvement anyway. I'm looking at a 25.5 hotchkiss hollow bar (like the lighter weight and the JCW I think already has a decent sized rear sway bar).

Including photos from the 2020 work. I'm really looking forward to tearing into the car this spring/summer... and really hoping I can cure the oil leaks.

Other future work goes cosmetic. I originally wanted a tan interior, but I couldn't pass this car up. So I'm working toward converting it. I also have the crazy sense of changing the feel to be more of a baby Bentley: how about re-upholstering the seats to look similar with the diamond pattern? And adding leather trimmings to downtubes and door cards? How about a chrome mesh grill?

 

I ordered a bunch of new parts from ECS, Way Motor Works, RockAuto, and a couple other bits from Amazon and the local Napa. Plus, I ordered new beige leather interior enhancements from Redline. I have to say a huge shout out to @WayMotorWorks - amazing customer service. I ordered from them the last time, and their service was equally as good then. They contacted me right away concerned that the coolant expansion tank I selected was backordered and suggested a different one that could be shipped right away, and made sure I got the right cap to go with it. A little back-and-forth and it was all shipped and received very quickly.
Anyway, let's get this party started!

Front-end service mode, right fender liner removed, ready to tear in to it.


It definitely seems like the majority of the oil leak is coming from the left side. I still can't quite tell where - probably some is residual from past leaks fixed but not cleaned. I can tell there is probably a valve cover gasket leak in the back and it's probably also leaking from the oil pan on the front left.


This has been a California car all its life, so I was surprised to see the condition of the valve cover bolts. Order placed with WMW for a new set.


At first I thought, woah, I caught this just in time. Look at those marks from the crank pulley. But after looking at the old pulley, I didn't see any indication of rubbing. And the pulley _seemed_ fine. The front main seal looked good too, especially for all the oil leaks everywhere else. I'm wondering if they had been replaced already. Oh well, I already have the parts and there is value in having a comfort level knowing what and when parts were installed. I do feel a little bad about replacing what seem to be perfectly good parts. In the long run, it's not a big deal. That front main seal was the biggest challenge - trying to get it out. I tried the screw method and that didn't work. The "push it in one side and it pops out the other" worked best for me after trying different picks and everything without trying to damage the crank or cover.


Out with the old, in with the new. What do you do with the old tensioner and pin in it? Do you toss it with the pin in it, or is there a way to remove the tension off the car so it goes a little more safely into the trash? I haven't seen anyone mention this predicament.

It's a busy week at work, so I'm looking forward to next weekend - finish up the pulley install, refresh the supercharger oil, then get started on the top of the engine bay. Good times - I enjoy wrenching and just wish I had more time, money, and space to do it more often.

 

Wouldn't it have made sense to release the tension while it was still bolted to the car?

 

That, I'm sure, would make too much sense. If only I had some.

I felt it needed to be pinned to remove it, but perhaps not. Regardless, there's still the lockout holding spring tension. I think I'll wire it up, compress the spring, snip the lockout, and carefully release all the tension.

 

Starting to put things back together feels good. And I can't wait to get the car back on the road!... hopefully without oil leaks, sounding healthier, and feeling stronger.

New thermostat with aluminum housing. The old one seemed fine, but this gives me more peace of mind.


Replacing the valve cover gasket and bolts. The old bolts actually came out just fine and didn't seem as bad as they looked. Still, new silver ones look fresher. The old gasket also didn't seem that old - still pliable, so probably already had been replaced not too long ago. And the valvetrain looked clean without any noticeable wear. Even though I ordered the gasket kit with spark plug tube gaskets, I only got the cover gasket, so just didn't do the spark plug ones. They didn't seem to be leaking and I can't imagine it's as common of a leak as any of the others. All good and still more peace of mind.


I bought both hoses connecting to the power steering fluid reservoir because something there was leaking a lot. For the life of me, I could not manage to get to the banjo bolt on the back hose at the rack, so I only replaced the one in front that is all hose and no metal pipe. The old hose was definitely brittle and seemed to be the likely culprit. Fingers crossed I don't have to try again to get to that one bolt - it's just impossible to get to it and have a swing of a ratchet. Probably what it needs is a swivel, super long extension, and an impact gun.


The old spark plugs didn't look too bad. I was worried they might still be the originals, but clearly had been replaced at some point. No real weird deposits and not too worn. Still good to put new ones in.


After a long weekend, fingers stiff and abs sore, it was time for some B-vitamins from the homebrew! I also got the Canton aluminum expansion tank installed, hoses replaced (except heater hose system or whatever that crazy set of smaller hoses are), MSD coil in, and supercharger sort of back on. Getting the supercharger back in place with everything connected right is going to be a real challenge. It's like you need 5 hands to guide things together all at once, but you can't even fit one hand in there. I'm hoping that with fresh hands, back, and abs it won't be as hard as it seemed. I can't be getting too old for this. Things definitely take longer, that's for sure.

Oh, and I guess I didn't take specific photos of it, but I changed the oil in the supercharger - the old stuff was old and nasty, but there was plenty of it on both sides. The water pump looked decent, but I'm happy to have a new one in there. And I put a new flange on the block where the pump connects, with a new o-ring.

Maybe next weekend I can find time to put the rest together and get the oil pan gasket replaced.

 

I wish I could get an aluminum thermostat housing for my car, but alas, I'm stuck with the stupid plastic one.

The power steering hoses are notorious for leaking; I've changed one of them several times. IIRC, the easiest way to get to that banjo bolt is to go in through the driver's side wheel well with the inner fender removed.

 

"I can't be getting too old for this. Things definitely take longer, that's for sure."
I feel the same way! I'm getting ready to dig into the Sidewalk's front end for a MESS of stuff in the near future...frankly, not relishing the idea but I DO get to live vicariously through you in the interim! Good luck on the rest of the project

 

It my experience a good hose clamp to replace the oem band clamps will fix the leak 99% of the time. The rubber lines get a little stiffer and the band clamps no longer hold as well as they should. I add a liner clamp and tighten until the hose will no longer rotate on the power steering pump barb. Less frequently do the fittings at the bottom of the reservoir leak, but I generally replace these too just to be safe. Cheaper than replacing the line assemblies and basically just as effective.

 

I haven't had an OE oetiker clamp on my lines since 2014.

I should add that my experience has been that swapping to a normal hose clamp will solve the issue for a while, but it’ll still leak again eventually.

 

Fair point. That's the problem with worm gear type hose clamps on aged material. They almost require yearly adjustment to maintain proper function. I do it every spring and fall on my 33 year old Z, and regularly poke around the mini so I just take it for granted. For a set it and forget it...replace the lines.

 

Mine got to a point where no amount of tightening would fix it.

 

I agree - the worm style clamps are not great for long term and can't fix hoses that have gone past the completely dry, brittle, cracked stage no matter how tight you can get it. That's also why I like to keep the spring type clamps for radiator hoses - keeps continual clamping pressure. But I don't think they're strong enough for the power steering hose. I dislike the oetiker style clamps just because they are hard to re-seat. But at least they don't loosen over time, unless you account for shrinking rubber hose.

So, what have I done for clamps? I've kept the spring type for the coolant hoses. I kept the oetiker style for the air intake hoses. And I got really nice worm style clamps for the power steering hose.

I watched some guy's youtube on worm style clamps so I could figure out which ones would be best for me. I finally got completely fed up with the cheap ones you get at Harbor Freight - especially on my homebrew draft setup - drained too many 20# Co2 tanks. I ended up getting Norma Torro hose clamps through CAP Hardware Supply. They are miles and miles better than the HF cheapo clamps.

 

Last weekend I was able to get the supercharger and all connections back in place - whew! Put a few bits and bobs back on to get things closer to finished. And I replaced the oil pan gasket.

Woah, the oil pan gasket was definitely needing replacement. This was dry and brittle and clearly what had been leaking all over. It was even leaking into the bellhousing for the flywheel and clutch - so much that I'm amazed it still worked fine. In hindsight, I should have checked closer to see if I could tell if the rear main seal was contributing to some of the leaking. I'm hopeful not, but I guess I'll know after I get it back on the road. It's the only spot left that could leak oil, and I wasn't going to get into that on this go around anyway.

I found this cool little aluminum nugget in the bellhousing among the oil leak gunk. I don't know where it could have come from (though I guess there's really only one place, but not sure how that could happen!). It had been thrown around a bit and made little nicks in the side of the oil pan. Otherwise, though, everything seemed to be fine in this area (operationally before the tear-down and visually).


I saw nothing out of the ordinary on the bottom end. The oil pan was pretty clean - no chunks of metal or shavings or anything. So glad to have refreshed this pan gasket! Fingers crossed I've caught all the leaks.

This upcoming weekend I should be able to get all the mechanical buttoned up and the car back on the road. What's left: low speed fan resistor, fuel filter, put radiator and front end back on, fill with fluids, and bleed coolant and power steering. I'm pretty excited about that, and can't wait to hear and feel how much better it runs, not to mention no more oil leaks and a sense of a more reliable car with many new parts.

 

Update from last weekend. No photos because it's mostly just putting things back together, or there's a ton of photos already out there that look exactly like what I did.

Replaced the low speed fan resistor. That wasn't too hard. The old one didn't look too bad and was probably still working. Hmm... but the fans still don't seem to be coming on. I'll think on that more later.

Replaced the fuel filter. Woah, that was a lot harder than I thought it would be. Probably the hardest thing of this whole exercise. Working in gasoline just isn't fun, add a couple complications and it's very not fun. The clipped on float piece to the filter body fell off as I struggled to open it up. Getting it back on was really hard because it got bound up with something else and wouldn't line up properly. I had to take the body and float arm further out of the well and then was able to position it better. Regardless, it needed to be done - 15 year old filters are never a good thing.

Firing up the car, it sounds MUCH better. No more weird noises or vibrations or hesitations. I cycled the steering while still up on jacks to make sure that system is bled. I topped up the coolant to make sure that was bled (hopefully!). I actually left the coolant bleeder screw open on the upper radiator hose over night and a bit leaked out. So I'm hopeful that is good. Checked the oil and topped that up.

I was about to put the intercooler cover back on and realized that a bracket was missing all along (no wonder it was missing a bolt when I bought it). Luckily I had a good starter bracket laying around that just needs some minor modifications to make it seem as if it was the stock bracket.

Now why does the fan and power steering fan not turn on?! Argh. I pulled the relays, jumpered the socket, and the fans turned on for both relay spots. I'm hopeful it's just bad relays. I ordered 2 new ones from RockAuto, so we shall see.

Next weekend, I can finish putting the bumper cover and inner fender back on, wheels back on, and get it on the road! And maybe I can also start in on the leather bits for the interior.

 

Everything buttoned up and the car runs great! There may still be a little leakage from the transmission, so a project for another year… but all pretty good and dry for now.

The radiator fan and power steering fan still has me concerned. I replaced the relays, but the fans still don’t seem to come on. Maybe the car just hasn’t heated up enough and the AC isn’t building up enough pressure to get things going? Based on the wiring diagrams, it seems like the only thing that could be off is the computer somehow. At least it’s proof this is still a bit of a British car with Lucas, the Prince of Darkness, still rearing his head (despite Lucas now being of German descent?). More testing is needed for peace of mind.

 

At least I got confirmation the fan comes on. After driving home from work and backing into the garage it finally got to 212 F or so. It never got above 200 on the way to work in the morning or in the way home in the evening. So that’s a relief.

BUT, it still leaks some sort of oil. Ugh.


After a couple drives - hence spots in different locations.

I’m guessing this is rear main seal. I won’t have time to check this weekend, but will jack it up next weekend to inspect. I was hoping it was residual drips of gunk, or was too slow to care about immediately, but this doesn’t look good to me. I really don’t want to pull everything apart again to do the seal, but I think I’m going to have to. My plan would be to just replace the clutch and throw out bearing with stock. I don’t track the car or drive it much anyway, and it’s only got 88k miles on it, but if there is anything else or something different I should do “while I’m in there” then I’m open to it.

 

Well, my latest mini also experienced the same issue. After fighting the inevitable I remembered your post and just ordered a new hose. Immediately leak free.

 

Saturday I pulled the ignition switch in hopes of solving 2 issues: occasional no-start (turn the key and just nothing), and the windshield wipers would randomly come on and nothing would turn them off except turning off the car. And, just before I delved in, I noticed random tail lights and headlights on without the key in the switch. It wouldn't even be both tail lights - just one of them. Weird. Anyway, it didn't look bad and there was nothing totally obvious, but it is hard to see details down in there. I cleaned with some electrical cleaner and rubbed between the contacts with the rough sides of a screwdriver, and rubbed again with very little dielectric grease. So far (knock on wood), solid starting and my random windshield wiper going on and not being able to turn it off hasn't happened again. Lights seem to operate as intended (except the 3rd brake light which is it's own issue of corroded terminals on the male plug end (not sure how to solve that).

switch looks fine inside

switch looks fine inside

Then, on Sunday, I replaced the upper front shock mounts. The right side was visibly cracked, the left side looked fine. I replaced them both with OEM mounts for the full refresh. Hopefully that solves the little bit of wambliness at highway speeds and is safer for the 200 mile drive back to it's home on the central coast for the winter. No photos. But, of note, the left side shock assembly was easy to extract from the knuckle - just like ModMINI showed, but the right side was impossible. Similar to a few comments in his vid, there was still about 1" of shock tube in the knuckle. I could spin the shock, so it wasn't stuck, but the knuckle just didn't have the movement. I popped the lower ball joint and then was able to drop the knuckle to easily get the shock out. Getting it back in was a little tricky - just getting everything lined up while it was all loosey-goosey. All done in just a couple hours and all is good.

 

Darn. I guess i spoke too soon. The windshield wipers came on again this morning. So weird. The only thing I saw going through a search here is a low battery, but my battery should be fine. Any other suggestions? I have a scanner which showed a lot of things last time I checked, but they are too cryptic to me. Maybe I can download a list and post them up to see what others can make of it.

 

It's time for my 3rd Deep Dive into the Mini. This summer's project is the rear main seal (and clutch, etc.). I don't think there is too much left to do in the engine bay "while I'm in there." Some considerations include:

- Valeo clutch kit (already ordered)
- rear main seal
- check the oil cooler and housing gaskets for leaks
- check the exhaust for that typical spot that seems to fail and needs to be welded up (I think I may have an exhaust leak)
- replace the power steering hose I couldn't get to before (already have it on hand) and hope that clears up the remaining PS "leak" (more of a general misting or something weird)

Meanwhile, during my first session of tear-down, I found some ugly going on.


It looks to me like the battery terminal is arcing up to the strut tower brace (WMW version). Maybe there's excessive play in the engine mounts under acceleration it gets too close? That seems weird to me. I don't think I've every run across this in the forums. I have replaced the dog bone and the right side engine mount, so the engine shouldn't be moving around that much. The terminal box was solidly connected to the air box and the air box was solidly fastened down. So, yeah, I gotta figure this one out.

Photo of end of day 1 tear down. I would have gotten further, but spent the morning waxing the bigger beagle taxi (no, that's not a euphemism).

 

Do you plan on removing the engine along with the trans to replace the rear main and clutch? I ask because when I changed out the clutch in my Mini I only pulled the transmission. It was a bear to get it in and out because there is limited clearance. While I was wrestling to get the trans out and then back in I worried the whole time that I would puncture the AC hard lines that run along the frame to the firewall. I wonder if it would have been easier to remove the engine and trans together.

 

I seriously contemplated it. After watching ModMINI a few times, I felt it would be easier for me to leave the engine in the car. I don't have a ton of space to work with, so a cherry picker and space to hold the engine didn't seem possible. As it is, I'm not sure where I might store the subframe while I monkey around with the transmission.

Thanks for the heads up on the AC lines - I'll take special care with them. Then again, I'm not sure the AC works well (I checked and it is charged), and putting the top down is pretty good air conditioning

 

That's not arcing, that's heat. 12V isn't going to arc through plastic, or much of anything. I'd suspect extra load due to failing starter, excessive cranking, or something along those lines. We recently discovered the same symptom on a mini we brought home last year.

 

Thanks for the tip megaDan! That is super helpful. I was thinking, if that plastic isn't enough of an insulator, then what could be?! The overheating/loading makes more sense. Though I don't know what that might be, and why it shows up in that spot? My rear window motor/mechanism recently failed. I wonder if that could be a cause? I think the starter is totally fine and it mostly fires right up every time.

 

Thats what i was thinking, something shorted or someone tried to start the car and was on a battery tender or charger and starting cranking it for a long time