Hi all,

I need some help and guidance on a timing issue I am having with the N13 engine. I have read through the other posts here about timing chain replacement and the procedures for the N14 engine.

I have tried to narrate as accurately as possible the sequence of events that led to the situation. Might be a long read, Apologies for that.

I have a Mini Cooper S from 2010 and a BMW 116i from 2014. they have the same engine but called the N13 in BMW and N14 in the Mini. I had replaced the front crank seal on the mini a few years ago and now had the same issue on the N13. and its a 1000 times simpler in the BMW as there is only the intake airbox to be removed. So I went ahead and pulled everything off and extracted the old oil seal with the help of two screws.

I had the 18 mm socket with the breaker bar on the centerbolt to turn the crank for verifying smoothness and cleanliness of the hub to assemble the new oil seal. It was around noon and about 47degrees Celsius where I am, so went inside the house to cool off and had a chilled beer!! after a few mins I came out and thought I would just start the engine and use a microfiber cloth soaked in brake-clean to clean off the crank hub as it rotated for a through clean.

As soon as I stared the engine I heard loud clanking sound and the engine stated to cough and rough!! i immediately shut it off realizing i had forgotten about the socket on the centerbolt!! went out and checked and surly the center bolt had come loose as the Breaker-bar had caught the subframe and the engine spun to loosen the bolt. so i tightened the bolt and rotated the engine by hand but felt no interference of valves and piston.

since i don't have the timing tools and most workshops here also don't, i fabricated the crank locking pin after measuring the hole on the flywheel housing. Went ahead and removed the valve cover, locked the crank, loosened the center bolt and rotated the cams ( which has the locking faces and writings facing sideways with the crank locked) to have the writing and flat face of the locking position, straight up. Tightened the center bolt and rotated the engine by had for two full rotations of the cams and checked the crank locking pin which fell straight in when I had the cams facing straight up.

I them put on the valve cover and started the car and it fried up straight away with a smooth idle. About 10-15 seconds later as the idle slowed down, the engine started fluttering and coughing and i shut if off immediately. Checked the error codes and had codes for both cams out of range.

So went back to this forum and others to find more info about timing. I then found out about all the pistons being at same height level when cams and crank are locked in position for timing. Removed the valve cover and the spark plugs, inserted soft plastic straws in the cylinders and rotated the engine to have the cams straight up as in the locking position. The pistons were not all at the same level but slightly off the same height. Checked it a few times but that was that. And the crank locking pin fell right in every time the cams faced straight up. So the engine was out of time !!

I then thought what if there were more than a single hole in the flywheel. Got my daughter to help and rotate the engine with the socket on the center hub while I checked the flywheel for holes with the locking pin. Turned out the locking pin fell into a hole on the flywheel about 5 times every rotation!! and ofcourse the pistons were all at different height every time except once. Next i rotated the engine and stopped every time the pistons were at the same height. Out of the 4 times they are at the same height in one cycle (2 rotations) the crank locking pin fell in only once. Checked it a few times and then loosened the center bolt and rotated the cams to straight up position with the crank locked, at the only position it would, with the pistons at the same height. Both cams are aligned amongst themselves and face straight up in sync. Tightened center bolt, rotated the engine a few times and checked. The locking pin fell in place every time the cams were in the straight up position. Put everything back and started the engine. It started straight up and had smooth idle. I kept it running at idle and it ran fine and smoothly for about 10 mins and no codes. Then I started the engine a couple of times for 10 15 mins during the day and all seemed fine. No error codes or rough idle.

Next morning. I took the car out for a drive to the gym and all seemed fine until about 10 mins later Drive-train error popped up. Checked the codes while driving and they were for camshaft angle outside range for both cams. The engine went into low power mode and boost deactivated. I could erase them while driving but the message on the car center would not go. At the gym, I erased the error codes, the message on the car display disappeared and I then went to the gym. Came back after an hour, started the car and drove off. This time the drive train error popped within a minute.

This is the current situation. No codes when stationary, at idle or when reved while stationary. Camshaft out of range error pops up within a minute when driving with the engine warmed up.

These are the questions in my mind:
1. Any probability of bent valves? Considering the major symptom of rough idle being absent.
2. Is there anyway of checking timing without the cam locking tools?
3. Is there any chance of both cams being out of sync even though the cam stretch bolts for VANOS sprockets were not loosened? The loosened center bolt allowed the timing chain sprocket to slip and caused timing misalignment
4. Does the 2nd sprocket (behind the timing chain sprocket) on the crank have to be in any kind of alignment?
5. Is it necessary to use the pre-tensioner tool before locking the crank nut?
6. is it al all possible to get the timing right without the locking tool kit? As the JCT one is almost twice the price and has a minimum 3 weeks delivery window!!

any suggestions or thought would be of great help.

Thanks

 

Couple thoughts ---
N12 and N14 were used thru 2007 - 2011, then replaced by the N16 and N18. Are you sure your 2014 is an N13?
-As you discovered, flywheels are obviously different. I've attached a pic of my original Flywheel.
-Pistons of equal height also needs to have #1 on the way up, not down. Timing is set at 90 deg BEFORE TDC. N14 crank will lock for EACH full rev --- it can be locked 180 deg out when cams are also rotating.
-Never, never rotate the engine CCW with chain attached. Vanos units get very unhappy and will screw up timing. If you miss the locking hole, DO NOT turn it CCW, go for another two full revs and SLOWLY approach the locking hole. This could be the cause for your latest code, Vanos trying to adjust.
-Chain needs to be under tension when setting timing.
-Cam and crank bolts are TTY and need to be replaced every time. Torque settings are extremely important. Not too long after N14 was introduced, crank torque was updated from 50Nm and 100 deg rotation to 50NM and 180 deg rotation. Apparently the bolt was working loose causing major damage.
-When assembling the crank sprockets, sprocket, hub and crank mating surfaces need to be oil-free. Friction is what keeps timing from going out of adjustment. Oiled surfaces minimize friction.

Your questions ---
1. Bent valves are very possible. Suggest doing a compression test.
2. BMW uses timing tools and a feeler gauge to check timing.
3. Out of sync with each other, probably not. Out of sync with the crank, definitely.
4. 2nd sprocket is for oil pump and is not sync'd, it is completely random.
5. Either use a tension tool or the actual tensioner. Chain must be under tension when setting timing.
6. I know of no other way to set N14 timing correctly and safely, but I'm a DIY'r, not a pro.

Personal opinion --- N13 obviously has different features than N14, as you discovered. Before you screw something else up, invest in a good repair manual and tools, or take it to an authorized BMW shop. If you choose to ignore my advice, I'm also attaching a BWM procedure for replacing the N14 timing chain. Maybe you can learn something from it, like how to set timing without proper tools.

 

Hello oldbrokenwind, I know this thread is old but, do you happen to have the BMW timing chain replacement procedure for the N12 engine? Mine is an 2009 base with dual vanos sprockets.

I am doing my timing chain and I’m a little worried about the reassembly process and making sure everything is still in time.

My biggest concern is making sure the cam sprockets are locked before I put them back on. Is there a simple and easy way to ensure this?

Oh and I’ve heard differing orders in what to torque first, for example I’ve heard to go intake to exhaust then to the main crank but other sources contradict this and other methods as well. What’s your opinion the correct order?

Thanks, 150kMini

 

Here's a link to the procedure you need --- it's one of the many shown on this page --- https://bmwrepairguide.com/category/mini-r56/

After doing this procedure for a couple times, I've found that the easiest sequence is to tighten the crank sprocket first. Then it makes little difference which is next, intake or exhaust. However, for the first time DIY'r, follow the procedure --- don't make any changes 'til you understand what you're doing.

Things to consider:
- When the chain is installed and the crank is rotated, DO NOT rotate the crank CCW
- Do not rotate the crank when cams are in place and the chain is not installed. This causes valve / piston contact and bent valves.
- When crank is locked, cams may be rotated to any position without causing damage.

Have fun and best of luck ---

 

150Kmini, when you retightened everything. Did you remove the tensioner pressure? If you don't have locking pin tool, you probably don't have the tool used to set the pretension either. It can be worked around. However, if you left the tensioner tight when you set and tightened everything the chain will be too tight to allow any minor movement of the cams when the engine is making extremely small cam moves. I believe some of these movements are not in tandem, but independent of each side.
Just a heads up.
Good luck,
Briscoe

 

Thanks for the info Briscoec. I did purchase a camshaft locking tool that came with the flywheel pin. I was just a little too concerned than I should have been about the phaser orientation when putting them back on.

To answer your question, no I did not release any tension from the chain. I just used the new guide tensioner that came with the kit once everything was hand tight (the phaser bolts and the crank bolt) and I had torqued the guide bolts down I torqued the new hydraulic tensioner to spec (My research found two differing specs 65nm and 80nm. I went with 65nm because I commonly saw the 80nm spec on N14 engines and not an N12 like mine) then I torqued the Crank and phaser bolts to spec (20nm +180* for cams and 50nm +180* for crank) similar to this guide here: https://bmwrepairguide.com/mini-r56-...er-n12-engine/. The tool I bought did come with the pretensioner, but I didn't have a torque wrench that would go low enough, and I don't have the experience to know what 0.4 NM feels like on a normal wrench.

Before starting I turned the engine over by hand, didn't feel any resistance and didn't hear anything tapping each other, and checked the timing and nothing moved. both tools fell back into place on the cams together. after everything was put back together, I pulled the fuel pump fuse and cranked it twice but still didn't hear anything like valves hitting pistons. So far, I've put 150 miles on it since I changed the chain, and all is well so far.

 

I believe the objective of the pretensioner tool is to leave a small amount t of slack so the cams can move. I belive they move small amounts independently. Very small amounts as in degrees. However, when fully tensioned they can't move and it will give your engine an error.