Quick Background:
Was on a long trip at steady state and suddenly there was a mild pop, check engine light began flashing, pulled off to the side of the road and the engine started sounding like a subaru. I brought the car to the dealer and they seem to think it is a valve seat after inspection as there is no compression in Cyl 1.

First, no leak down test has been performed yet.
I took some pictures inside all cylinders, There are some weird circular patterns on some of them but looking at other pictures of disassembled motors, they are there. Piston in cyl 4 has some crackly carbon but needs a better picture to determine what it truly is.
Take a look below

I am going to take the head off the car and am going to get the cam locks and crank locking pin to start, any other specialist tools that I might need that I am not thinking of?

 

You can remove the head without using special tools. They're only needed for putting it back together. Then you'll also need:

Timing chain tensioner for re-assembly.

If the fuel injectors get removed --- for machine shop work, you need a special tool to replace the seals. Or, take the head to a dealer for them to install the seals.

A Bentley Service Manual is highly recommended --- torque settings and tightening sequence, and which bolts are "stretch" or TTY bolts.

Have fun with this task ---

 

That last pic looks bad. Is that #1? Looks like detonation damage to the edge of the piston, if I'm interpreting the photo correctly.

You may have more work to do than just R&Ring the head.

 

Looks like you have a valve/piston strike mark on top of piston. Either that's carbon hanging off the edge of the piston or like Slave to Felines stated detonation damage.

 

I found more information from the car when it was diagnosed by mini. Compression test found 5psi in cylinder 1 and 160psi in 2,3,4. Leak down on cylinder 1 found 90% of leak down out the exhaust. I plan on taking better pictures of cylinder 4 as I thought it was strange. I probably will still take off the head because worst case, I will be replacing the motor, best case, rebuilding the head.

 

160 psi for compression is great, 170 psi is what it should be on a brand new engine. Expect your numbers to go up slightly after you head job, if you have more than 50,000 miles I would suggest all new valves cause you never know when your going to have a burnt, broken valve.

 

Does anyone know where I can send out my head to get rebuilt in the states? I just want to see if anyone knows any places who do good work or a specialtists.

 

My favorite is a specialist --- Thumper Performance, located in Florida, check out his website or use his email --- <thumper460@hotmail.com> This is the guy that did all my head work. I'm guessing he will also do basic head overhaul / repair. If not, he might suggest someone else.

Shipping costs can be rough. You might want to check in a nearby major city for a reputable high performance (I'm biased) shop. Basic rebuild shouldn't take special knowledge, unless there's something unique I'm not aware of about these heads. There's also a couple NAM sponsors that you could check with --- lotsa options.

 

I took some more pictures today and changed some settings on my camera to get a better look through the spark plugs. Cylinders 2 and 3 are of no concern. Cylinder 1 has these weird markings and appears to have some deformation to the piston.Cylinder 4 has some debris sitting on top of the piston. It almost looks like a piece of a valve and some carbon.

Cylinder 1 pictures are the two to the left.
Cylinder 4 is the one to the right.

Thoughts? I am starting to think possible timing issues.

 

A valve strike, looks like a freshly made mark to me being it's all shiny. The valve don't always break off when they come into contact with the piston.

 

So I am thinking the motor is toast correct? I would assume that I can't run with the pistons like this. There was a similar incident to this that was a result of timing chain issues after the timing chain and guides were replaced.

http://atlanticmotorcar.com/2007-min...nt-and-update/

 

If you plan to get the car running again, you'll need to at least rebuild the head. I'd also remove and inspect the pistons for physical damage. It would be a shame to rebuild the head, only to have a piston give up. At least go that far before re-assembly. Depending on your experience, you might want to find a reputable mechanic to do the inspection. Rods and / or pistons can be replaced without pulling the entire engine, and for a daily driver with minimal upgrades, this will get you back on the road. If you're looking for "rebuilt engine" performance, an '07 probably needs a re-bore which means pull the block.

So, the motor is "toast" only if you want it to be.

 

If the block is alright then just replace that one piston with visible strike marks and a re-build head. If it were me I would just go ahead and re-build the head and all pistons if the cylinder walls are alright.

 

Just went down this path - tried to pull the head off my '07 MCS this weekend and now I'm waiting for a cam timing tool kit to finish getting it out.

A few lessons learned...

I didn't use the bentley manual but I ended up scouring the internet for tutorials and schematics to make sure I took things apart correctly. I highly recommend you just get this manual before wandering too far beyond the parts of the motor you may already know. I wasted a lot of time...

Unless you have a killer air compressor, you'll want to have the cam timing tool set before you start to mess around with the chain, etc. The only ways I can see to remove the cam gears are with the tool set (I've read about people using a wrench on the cam, I'm not a fan of that idea since it's balanced), an impact ratchet, or by holding the crankshaft with a 1/2" ratchet and using the chain to hold the cam in place. If you do that, you probably should replace your chain since you're likely to stretch it out and these cars are pretty well known for that issue already.

I also recommend some 1/4" long extensions and a swivel....the heat shield is a pain but doable without the front end slid forward in mechanical service mode.

You'll need both female and male torqs. The females are E8, E10, E12, E14.

The belt tensioner uses a 21mm wrench, or if you're like me and only have up to 19mm, you can wait until you pull the motor mount and lift the engine just enough to get a socket on there. I didn't bother to pull the belt, just disengaged the friction pulley.

Even after you drain out the coolant from the bottom line, you'll find a few cups worth left in the water pump lines....that was fun.

The downpipe was probably the most difficult thing to pull out. You may want to pull off the bracket that holds the bottom bolts on. Even after you remove the nuts, it really doesn't want to clear the bottom mount and the turbo exit at the same time.

Buy some blue, low-residue masking tape, bigger ziploc bags (you'll want things like the HPFP sealed up for the long duration it's out), and something to mark any bolts you can't put back in place because of the machine shop (like the harness conduit to head bolts).

Feel free to ask any specific questions as they come up.

 

For what the job is going to cost including the head rebuild, pistons, specialty tools, etc, would it not be worth it to just get a rebuilt motor and move forward? I don't know the exact figures but I know that if I do a motor swap I will be in about $4500 after the core is returned and I replace a few components while I'm in there. Inital head rebuild was aroun $2500 including all tools, services, etc, but with pistons and who knows what else right now, is it worth the risk?

 

It shouldn't cost you $2500 to fix the head. $1000 tops. I've seen completely rebuilt heads on ebay for $1000. Pulling the head won't cost you any more than pulling the entire engine, so if you're entertaining the work, you might as well pull the head and see what you're really in for.

 

So order the tools and take it off for a look see?

 

If you're 100% sure you aren't going to tow it somewhere as a trade-in, I say you might as well. You'll have to tear all this down to swap a reman long block in anyway. You should be able to resell the timing chain tool kit after too.

 

If you're going to have the head rebuilt why do you need the cam lock tools?

 

what I am asking is should I invest in the tools if I can clearly see impact between valves and piston? I could take the time/risk of rebuilding the motor when I could get a rebuilt motor from mini and have fewer potential issues down the road. Its the question of how much difference in price is thee going to be in the end if I rebuild the head and replace the pistons/inspect internals vs dropping in a rebuilt motor from mini with a 2 year warranty?

 

In the end you gotta do what you feel is right, if it was me in your position I would take advantage of the situation and have forged pistons and rods so I could handle more boost. To me my Mini is more than just a commuter, it's about driving for pure fun and is an adrenaline run pushing through those S turns.

 

I love the car which is why I am not getting rid of it. However, it is usually my daily driver up until a month ago when this incident happened. I am thinking just drop a motor in it and drive it for a while. I would get a 2 year warranty and peace of mind. Building the motor would be nice but, budget wise and risk of reliability is something that I do not want to give up. The car has a few addons that make it fun and have a little more power, but it is not a racecar and the cost of making it exactly how I would want it would be throwing money away.

 

There is a complete head for sale in the marketplace right now.

https://www.northamericanmotoring.co...-head-f-s.html

 

The timing tools just make the job smoother. In the big picture, not a huge investment. Unlike me trying to justify buying a lift for my home garage. Someday.

When we burned an exhaust valve, I got quoted $6300 from a MINI dealer. That gave me the push I needed to tackle the job myself. I had the Bentley book and this on-line group. A also had an engine specialist/machinist that I already use for my BMWs, so I knew where I was going. Spoke to him and figured out what parts he needed, then added up my list.

Since our (her) car had 100k and 7 years on the clock, I opted to just replace every seal and hose that would now be exposed during the cylinder head removal. The total job added up to about $3500, almost half of the original quote, but soooo many extras were completed. With all the extra work/parts I probably came in at 1/3 of the dealer cost.

Downside:
No warranty- I'm the mechanic.
My time- Lots of it.

Upside:
Reputation- My wife (and her friends) thinks I am super human for pulling this job off.
Knowledge- I learned a bunch about these cars and have a greater comfort level with them.

 

I am thinking that a rebuilt motor is the best option. It gives me a two year warranty on the motor and peace of mind when I am on the road that there won't be an unexpected motor failure because of something that I didn't see.