[ssashton]

Hi Eveyone,

Despite having a new fuel pump and some other parts (which helped it run smoother on power) my R56 with N14 engine still has a rough idle. That is not to say I get rev fluctuations, only that the engine vibrates more than I think it should giving slight hickups here and there. Better when warm but never 100% gone. It bugs me!

After reading about Vanos problems and finding a description that matches my symptoms I changed the Vanos solenoid to no effect. Now I want to check engine timing / chain.

Today I put the cams in upright position (TDC, or it could be crank at 180°) and placed a ruler on each of the the square sections where the locking tool usually goes. I took a photo with camera on a static tripod so I can compare intake and exhaust angles. I seem to have about 2.9° difference. See photo. I'm unsure if this is advance or retard?

Anyway, I wanted to confirm that this is not normal, is it? The resting position should have both cams with the square sections exactly aligned, correct?

Just counted the Vanos gear to have 40 teeth, so 9°/tooth. It's not slipped a tooth. Simply a worn chain or lack of tension?

I also checked the Vanos seals that feed oil from cam to Vanos. I read they are rubber on some BMWs and can wear out but mine seem to be steel.

Also I put a spanner on the intake cam and found I was able to move it slightly against the spring of the Vanos gear. It wasn't 'easy' but it was possible with one hand. Video below. Is this normal? I read somewhere it should not be possible to rotate the cam... but the Vanos is a sprung gear.

Insight appreciated!

Vanos cam spring:
https://youtu.be/WojmAbBXi78

 

[ssashton]

you can rotate the vanos with some force agaisnt a spring that thats it back to its start position every time, on start up both vanos will get loaded with oil pressure controlled by the valves and have a on idle slightly moved off the stops and as engine revs harder they rotate more,
2.6degrees on top sprockets will be a lot on the longer parts of chain to bottom sprocket, you need a locking kit and lock engine off correctly.. or if were me and car has done 60k plus on that chain kit just repalce it before it lets go and turns a £300-£800 depending on who doe it job into a 3k for new engine job, look at the chain tensioner how much of the end of the plunger can be seen measure it, a new chain kit will be around 5mm worn out 10mm-14mm

Thanks Mike. The car is only on 49K so it does seem early for a new chain but regardless it's an 07 plate so not a young lad anymore.

How can I check the tensioner length, please? I don't think I can see it from with the valve cover off. Do I just remove it, or then it will spring to full extension?

 

[ssashton]

I had a quote from my favourite garage of £660 inc. VAT for a timing chain replace. Ouch! I thought it would be about a 3 hour job for a practised garage. I guess I'll do the job myself. Are there any unexpected 'gotchas' I need to prepare for?

 

[ssashton]

Whats' the dummy tensioner for?

27mm thin spanner for the aux belt tensioner?

 

[ssashton]

I haven't retimed the engine yet but I was having trouble finding the cam stretch bolts without buying the Vanos gear and sprocket too. However I just found them by using the part numbers from RealOEM. So in case anyone else needs it the intake Vanos strech bolt is 11367536087 and the exhaust sprocket strech bolt is 11367545863.

 

[ssashton]

Okay time to give an update on this.

I re-timed the engine over the bank holiday weekend.

I used a cheap timing kit from eBay. Yes, I had to reduce the main body of the crank pin to fit the flywheel housing bore. I just stuck it in a drill and used a small file to work it down.

Also yes, the timing lock fixtures needed a little work. The exhaust lock needed a small section cut off because it interfered with the turbo (I think an extra screw hole for mating with another engine) the angle-grinder took swift care of that. AND yes, the locking fixtures needed some shimming to get a really snug tolerance fit on the cams. In my case the exhaust fixture needed 0.14mm shim and the intake needed 0.1mm shim.

Once I put the crank pin in, the exhaust locking fixture slotted dead-nuts on. Nice. The intake fixture on the other hand would not even go on more than half way because the intake cam was angled backwards towards the engine bay bulkhead. So yeah, it was out of time. I don't think it is chain wear because that would be spread across the chain evenly and appear on the exhaust and intake cams. In this case it was only the intake cam and I think it was probably not installed carefully since I found the valve springs wanted to push it off time just like I found it here.

I removed the timing chain tensioner and replaced with the manual tool done finger tight. I'm not really sure why I shouldn't just leave the automatic tensioner in there (except if you are replacing the chain).

In order to loosen off the vanos intake sprocket bolt I needed to remove the top brace / radiator mount and also remove the intercooler to intake manifold pipe. Using a swivel socket to avoid the engine mount I was then able to release the stretch bolt and adjust the intake cam relative to the sprocket / timing chain.

I installed the new stretch bolt (20nm) and did a few test rotations, then reinstalled the timing tool. Then I did it again to be sure before I torqued the bolt 180 degrees for final tightness and did a final third test rotation and locking kit install. Everything was perfect!

Oh, I will warn you that the tensioner hole is fed with oil. So I got a nice pool down the back of the engine when I did my test rotations with only the manual tesnioner tool in there.

The result? Well at first it seemed to run smoother. Then it didn't, then it did. I think this has helped, I mean it can't not help getting the engine timed right. However first I think I will need to have the adaptions all cleared so the ECU can learn the new timing. Second I have a suspicion I need to check the sensors and wiring. Yesterday I gave my MAP sensor a blast of alcohol to clean it and now the car actually runs worse than before, so I suspect a poor MAP sensor or weak wiring too. I battle onwards!

 

[ssashton]

Thanks for your help Mike, it's good to have you on this journey!

I'm doing a trip from Kent to Birmingham and back this weekend so that will give the car plenty of running and warm up.

 

[ssashton]

This is the one I ordered, but it actually came in a blue case and looks more like the one you linked.

https://www.ebay.co.uk/itm/BMW-MINI...4-1-6-TIMING-LOCKING-TOOL-KIT-UK/263309545823

The only reason it didn't like the turbo engine is because a small bolt hole needed trimming off, also on your blue kit there.

 

[ssashton]

I still haven't had the Vanos system and adaptions reset as I started to get fault code '2B64 - Intake manifold, unmetered air' and I wanted to check the MAP sensor and wiring first.

I finally got around to it today and have a new MAP sensor as well as checking wires and putting new connectors on the plug. Still the exact same situation.

SO - is it possible the 2B64 fault code is simply caused by me changing the engine timing and not resetting adaptions yet?

I have of course checked for vacuum leaks and can't find any.