N14 JCW engine, good, bad, or run away!
 

I bought a new 06 cooper S (supercharged version) and was quite happy with the car, put 78k on it and never had any real issues.
Now I am in the market for a JCW cooper clubman and wanted some feedback on if these are time bombs or if they can be reliable?
I know that the internals of the JCW are different and wanted to know if these are more or less reliable than a cooper S with the N14?
I have seen quite a few posts on this site warning of the N14 due to timing chain issues and build up on the valves.

thanks,

The big issues with the N14 can be addressed - get the revised valve cover to reduce the carbon buildup on the intake valves, and the updated timing chain tensioner. Then make sure to maintain the oil level and to 5K oil changes.

The JCW version has a bigger turbo, lower compression ratio, and revised ECU tuning but otherwise is the same engine. (might be a few other differences I am forgetting but those are the big ones, check realoem.com to be sure.)

It will never be an engine like in my Acura that has gone 300K with just oil changes, plugs, and a timing belt every 100K. But the issues for which the N14 became notorious can be solved.

Is the revised valve cover an aftermarket part or dealer item?

https://www.realoem.com/bmw/enUS/par...&q=11127646555

Is the part number visible on the outside?

Or do I need to remove it confirm which version I have?

To determine which one you have, figure out the production date of your car and then look it up on realoem.com. The updated valve cover design (link above) shows as superceding the earlier part numbers. It is a MINI part.

I have the n14 JCW 2012 and its been very good. I think the 2009-2010 JCWs had the most issues ( like the early non JCW N14s 2007-2010) with the older part timing chain and tensioner. And the newest valve cover and HPFP. On the cover the last 6 digits or show. The older covers I believe dont have the newer megplast logo on the right hand side.

Newest: 11127646555

These are the older part numbers for you:

Previous Revisions
11127561714
11127572854
11127585907

biggest issue with N14's is folks that listen to deal and try to run their low-weight oil, in a hot-ass little turbo motor for 10k before changing it.


JCW or 'S' .. its a turbo DI .. love it with oil @ 3-5k interval

hey ECS where do you find those valve cover numbers???

and do you sell the newer ones for the N14?

Yes,

We have those listed on the product page under Previous Revisions on most products,

For all valve covers, we have the newest revisions.

link?

Sorry here you go :)

https://www.ecstuning.com/Search/Sit...h/11127646555/

Then click in one more and look under product details at the bottom.

https://www.ecstuning.com/b-genuine-...r/11127646555/

Even if it's the slightly different JCW motor you're still going to have all the typical things that happen with the N14 motors. Thermostats, water pumps, carbon build-up, vacuum pump, HPFP, etc. Whether or not they're "reliable" is all a matter of perspective. I don't think they're that bad but I do all the work myself and have plenty of other cars to drive if the mini sits in the garage for a week. I've had worse cars but I've also had a lot of better ones.

I picked up a 2009 JCW back in December (2018). Had it shipped from California with only 36,000 miles. I have my previous 2003 JCW and I've been used to dealing with issues from time to time, but ultimately my MINI was usually very good to me. Trying to prevent these notorious N14 issues from developing in the future.

Is this (https://www.ecstuning.com/b-genuine-...r/11127646555/) the correctly revised valve cover you were referring to? And any info on what part to update the timing chain tensioner?

11127646555 is that latest cover.

On the timing chain kits: https://www.ecstuning.com/Mini-2009-...Engine/Timing/
Any of those have the updated newest tensioner and the chain/guides.

My 2012 n14 JCW With 67k miles has been solid, knock on wood. Timing chain replaced under warranty, walnut blast preventative carbon cleaning at 60k, and a recent thermostat change. Runs smoothly, and only burns about 1 quart of oil between 5k oil changes. Car is running great! I had much more maintenance issues with my old 2004 e46 330.

I have a 2011 n14 JCW with 52k miles. Did the dealer or independent shop (whichever you used) recommend 60k as a good time for the walnut blast? Or were there symptoms that indicated it was time?

Mine is a 11 JCW with 120K. No walnut blast ever needed. If you use top tier gas like Chevron Supreme which I have on both MINIs since we bought them and run it at highway speed regularly. You don't need walnut blast.

My shop, Helix Motorsports, recommended the blast at 60k miles. I did not have any symptoms and did it as a preventative measure. Car seemed to pull a bit harder afterwards.

I pretty certain that using "top tier" gas or Italian tuneups does nothing to alleviate carbon buildup in direct injection engines. Run a search, as people have discussed this.

lol do what you want. Of course they're going to hustle the walnut blast. It's expensive.

I've lived and breathed this car for the last 5 years. Both my wife's and my JCW. I've checked out every maintenance issue and mod opportunity.

If you run sh*t gasoline, and don't highway your JCW - it'll need a walnut blast like 100k. They can carbon up fast on Domino Pizza delivery driving hahaha and crap petrol. I run my JCW at highway and often at 90+ at least once a week. Never had a carbon build up issue. I also time out my turbo at 5 minutes and it runs great at 120K which is old man age for a MINI turbo.

The dealer that I use to take my JCW and MINI to that would sell the walnut blast is now out of business. hahaha And when they liked me they stopped pushing it. Actually they never pushed it. They were pretty reputable. Do what you want. If you're not feeling sluggish performance, don't make a timer on the walnut blast. Best things you can make a timer for is timing out your turbo before shutdown. Change the oil frequently and totally keep it top off. Change the air filter regularly and change the plugs every 25-30K. Change the ignition coils every 50K. That'll burn out the carbon buildup with top tier gas. Anyway good luck.

Well, I may end up needing it simply because I rarely drive at highway speeds. I have no commute to work other than the very rare meeting and all of my errands are within a few miles from home. I do make an effort to take the long way and get up as much speed as I safely can but still... FWIW I fill up almost exclusively with Costco premium which is what the dealer mentioned they recommend and is exclusively what they put in their cars.

How exactly does the quality of your gasoline have any impact on the cleanliness of the intake valves on a DIRECT INJECTED ENGINE?!? The fuel NEVER touches the intake valves because it is directly injected into the combustion chamber after they are closed.

I just got off the phone with a Mini Repair shop that claimed he gets calls every week for N14 owners that have blown their engines! I'm in a bit of shock at the moment having zero problems with mine since the I had the timing belt tensioner changed in 2011. (2009 factory JCW) I don't understand how could this be so widespread and I'm not seeing this forum blowing up with comments...

My N14 is still running well. I suspect blown engines are from non-enthusiasts who follow the recommended factory oil service intervals, and don’t check their oil levels between changes. Low oil levels and then boom. I think most people on this board are pretty vigilant on oil levels and odd timing chain rattle noises. Ask your shop why all those N14s have failed. These engines are fairly solid when well maintained. In comparison, jump on Rennlist and take a browse through the 996 and 997 forums at all the big fears of catastrophic engine failures from IMS, bore scoring, timing chain guide failure, cylinder chunking etc. Break out your popcorn and enjoy your N14!

Also, I just saw MalibuJoeys comments in response to my prior post. He obviously has no idea what he’s talking about with fuel and direct injection. Further, I did my walnut blast at 60k bc I do a lot of short trip driving to the train station in daily commutes to work. At least I used to, pre-COVID-19 ...

I use a indi shop that specializes in BMW and MINI. They say very few blown engines, the few that he sees all have little or no oil in the engine.