This is my first post on this forum and I find myself in the unfortunate position of having to carry out major repairs to my 2010 Cooper S. I have zero compression on #2 cylinder and low compression on the other 3. A wet test showed an increase on the 3 low cylinders. Having found this I have determined that at the very minimum I am looking at a valve job and a set of rings. However, I won't hold my breath on that best case scenario. I have not taken it apart yet as I am in the process of ordering the cam timing tool kit but I would be grateful if anyone can tell what if any other specialty tools I will need to carry out the repairs.
Welcome to MA! I'm not an R56 guy but it may have carbon buildup on the valves. If this is the case you may only need to have it walnut blasted. Have you had it checked? this is a known problem.
Carbon is the enemy of the N14/N18 DI engines. It can get bad enough to hold the valves open causing a loss of compression & if left that way long enough it can cause the valves to burn.
A valve job probably requires the fuel injectors to be removed. There is a special tool required to put them back in. Or, take the reworked head to a dealer / mechanic that has the tool BEFORE starting the re-assembly process, and pay them to put the injectors back in. Also, ensure your cam timing kit includes a timing chain tensioner. And finally, I had to get a set of tools for all the star and torx hardware (my 1st non-USA car). Other special tools are recommended but can be worked around successfully --- your choice. The Bentley manual is highly recommended --- torque settings and TTY bolts to be replaced. Best of luck doing it right, it's not a lot of fun.
Crashton and others have hit it on the head....I should know!!! I had the same thing on my 07 MCS...was unlucky enough to burn a valve. My first recommendation is to rent a scope and take a peek into the cylinders, it's quite easy actually. If you don't see a burned valve, which may be difficult due to carbon build up, I would try and remove the carbon...by hand if you have a valve that is stuck open (it's a real pita). If they will close, you can build your own carbon blaster for about 75$ and blast the valves yourself. I did my own repair and for the cost of the tools, it more than paid for itself. Where are you located?
I'm in sunny Syracuse, NY. I appreciate the feedback but based on what I seen on the spark plugs (I'll post pictures later) I am pretty sure it's more than just a de-carbon job. I have access to a scope given that I have one at work but like I said, the plugs tell me that I have some serious problems. #1 cylinder was missing a good portion of the insulator and #2 was seriously oil fouled. Plan A is to take it apart and determine the level of pain that I am facing. I plan on documenting this project in the hope that someone else will benefit from it. I have re-built a few engines but this is my journey into a twin cam 16 valve BMW cluster EFF. If I get lucky I will get away with the basics but I suspect that I am in for a major PITA.
Thanks for your reply, the one thing I didn't consider was removing and replacing the injectors. Do you happen to know why this procedure is complicated? Unfortunately, the nearest dealer is Rochester, NY which is about 1 1/2 hours away from me. I am looking at getting the BMW TIS, a buddy of mine has it for his 3 series but he said its a pain in the ass accessing the mini data.
One other thing that carbon does if you have enough you get spark knock - pre-ignition. From your description of plug #1 that seems likely. It can cause the ring lands to break too. I hope once you look it isn't as ugly as it sounds. :fingerscrossed:
A Teflon(?) seal has to be forced over the tip then compressed into a groove BEFORE installing the ass'y into the head. The compression process takes special tooling, as illustrated in the Bentley manual. Similar tool is used for other BMW injectors, but different sizes are used for different models. Some tool catalogs list applicable uses. Considering the cost of replacement parts, gaskets, and tools, Bentley manual isn't that much more. Again, best of luck. EDIT: This tool set has 5 pieces --- -"pliers/cutter" to remove the old seal -cone to install the new seal -3 "inverted cones" to compress the new seal The really essential part is the compression part. Once compressed, you have only a few minutes to install the finished injector, otherwise the new seal starts to expand to its original diameter, making it virtually impossible to install. These 3 pieces are similar, differing only in internal graduating sizes. Hard to explain in text.
I'll be pulling the intake today to get a look at the valves using a mirror I'll see if I can get a pic or two. Is it really necessary to remove the injectors to do a valve job?
If you have access to a borescope, those pics would also be usefull Considering your wet test results, you probably have worn rings in addition to possibly cruddy / shot valves. Walnut blasting alone will not fix worn rings. As I understand it, a wet test is only for rings, and will not determine valve condition. So, if wet test results differ from "dry" test, rings are worn. Either rings or valves require head removal to fix. So far, only you have the test results to know the magnitude of the differences. Injector removal is probably up to your machinist. Personally, I wouldn't want any foreign material, i.e., machine shop filings, getting into the injector nozzles. When I sent mine off to Thumper, he asked me to strip it completely. When it came back, the manifold studs were packed separately --- I didn't remove them, he did. 'Course, that was more than just a valve job! Maybe others following this thread will chime in with their opinions. I have zero machine shop experience.
Celticfc, here's my thread on FI seal replacement, complete with pics, pricing, and a source or two. Hope it helps. http://www.motoringalliance.com/forums/cooper-s-clubman-s-engine-drivetrain/21441-anyone-replacing-fuel-injector-seals-themselves.html#axzz3FxQ82Hog
Thanks for the info. I'm trying to track down the bore scope here at work to get a look in the cylinders and praying that the piston on @3 doesn't have a hole in it.
Does anyone know what the compression test and leakdown results should be for a good N14 motor? I have an option on one and have asked for the compression and leak down to be checked before I decide to purchase it.
I am not sure but you could call Chad at Detroit Tuned an ask. He would know. Detroit Tuned - 586-792-6464 Detroit Tuned MINI Cooper Tuning
When a Mini dealer checked my compression, the report indicated the results and "--- All cylinders are within 5% of each other and between 160-180 PSI. Checked OK." I put a lot of faith in this particular dealer. No clue what a leak-down test result should be.