I am in the process of removing the cylinder head on my 07 Mini S, and I am at the point where I need to remove the exhaust manifold. I have the vehicle in service mode, and been following Bentley Manual, but it seems the turbo is in the way of the exhaust manifold bolts a couple of them. Is turbo needing to be removed? Also does the catalytic converter need to be removed as well?

 

The catalytic converter is mounted to the turbo, remove the turbo to gain access the the exhaust manifold bolts.

 

Thanks for reply, got it all removed!

 

It's a great idea to have spare studs that bolt up to the turbo housing to down pipe. Sometimes they come out and the only thing to do is install a new stud, some have had to drill and tap stripped studs.

Glad you solved.

 

Great idea, so far mine look okay. Anything else you suggest I should replace besides the obvious gaskets while its all apart?

 

Why are you removing your cylinder head?

 

Timing chain guides broke, dipstick snapped in half and ultimately bent exhaust valves.

 

I caught on when seeing your other thread, I think your pistons are alright as long as those dents on the top can be smoothed out or it will glow like a glow plug when driving, not good. Bent valve equal messed up valve guides, your only option is a rebuilt head. I have seen other thread where a valve strike happen thousands of mile before the head of the valve broke off and the piston/head ate each other destroying the block as well.

 

Oh I see. How can the dents on top of pistons be smoothed out? Also, what would cause it to glow? I currently have my cylinder head at a local machine shop for a rebuild!

I apologize for my ignorance.

 

A few weeks ago I was reading how a member all of a sudden had one of his valve head shear off while at the track and he also had replaced a timing chain Death Rattle a year earlier (1st Gen R53) and when he took everything apart he noticed pretty much all pistons had those half moon valve strike marks.

He realized that the valve strike must have happened way back when he had the timing chain replaced because the timing chain he had when he ate the valve head wasn't stretched, it's measured slack was well with in spec. It took a year after the minor valve strike for the valve head to actually weaken and break off.

His other intake valves looked bent but hadn't broke off yet, you would think that the bent valves would have a problem sealing, but they were sealing enough. Later when I get home from work I'll pull up that thread, it's a fascinating read!

You have good psi readings for three of your cylinders and those valves are structurally weak, by how much is anyone's guess. If you 4th cylinder was like your others you would have no idea all your intake valves are weakened, you probably at some point would have ate your valve heads just like this other guy.

 

WOw! Oh alright I see. Ya don't want to deal with any major repairs again soon. So what your saying is most likely all of the exhaust valves are bent not just 4th cylinder but still sealing. Thus that's why there are marks on each cylinder? Do you think the pistons need to be repaired or are those fine?

thanks

 

I have looked everywhere for that thread I was talking able, I'll keep looking. It's even got multiple You Tube videos.

Remember when the engine is running thousands of RPM's a minute it might not sound like much but to the human eye it's bleary. When your death rattle incident occurred everything is moving very fast, I believe that when your engine lost timing your 4th cylinders valves was first hit the hardest, the others not so much. Your other three cylinders valves have to be weakened, to the extent of being bent, perhaps.

I'm most concerned about the durability and strength, the OEM valves are sodium filled valves and are great because they are better cooled. There also brittle and in some cases chunks of these valves can simply fall apart without contacting anything expect excessive heat over prolonged usage, the N14 engines are infamous for this caused by carbon build-up which in turn heats the cylinders causing burnt, broken valves.

As far as if your pistons are concerned I might not be the best to answer this question, perhaps someone else will chime in here.

 

Oh I see now yes this makes a lot of sense. Well, The head is at a machine shop now and I am waiting to hear what they find. I wont be surprised if they are all slightly bent, and even if they say they seem okay then it may be best to replace all of the exhaust valves anyways!?

Best Regards

 

I would replace all the valves since your rebuilding the head, might as well use new parts. Intake valves have been known to get burnt and have chunks break off after 50,000 miles do to the carbon build-up on the intake valves.

You should provide a link to your other thread.

 

Found this after doing some research, the sharp edge (your half moon valve strikes) will glow like a glow plug causing pre-ignition.