Timing chain tensioner.

[Calibrazxr750]

Wot ho, I was experiencing a few issues with the car, which led me to suspect that the timing chain might need replacing. Fault code for camshaft/crankshaft sensor bank 1, (poo16, if my memory serves me well), but I didn't have any rattling noise from the timing chain. So I thought that I would try and change the tensioner. The old one came out quite easily, but was in three pieces, the housing, the spring and i had to get the plunger out with a magnet. I put the new one in, but it was very easy to screw in until the last 2-3 millimeters, which is when I required the ratchet to finish it off. So, it is my understanding that they shouldn't be that easy to put in. I checked by putting a bar in to the hole and was able to apply a small amount of pressure and thus movement in whatever the tensioner presses against. I am now somewhat worried about starting it up and I am getting the chain replaced as soon as my mechanic has the time. Bottom line, has someone else changed theirs and was the experience significantly different from mine? Any help would be greatly appreciated.

I probably ought to point out that it is a 2011 200thp with 148,000 km. My mechanic thinks that it must have had the chain replaced at least once in its life, otherwise it is unlikely it would have achieved that mileage on the original chain. however, I have no idea if it has or hasn't been replaced at some time.

 

[Pedro]

Just turn the crank pully over see if the Engine turns freely the tensioner piston pushes against the timing chain guide rail if the chain is properly tensioned then you should have no problems the maximum stretch on the BMW Prince Engine Timing chain is 68mm when that is reached then you need a new chain & they rattle their heads off when that happens from cold start

 

[Jumper]

Wot ho, I was experiencing a few issues with the car, which led me to suspect that the timing chain might need replacing. Fault code for camshaft/crankshaft sensor bank 1, (poo16, if my memory serves me well), but I didn't have any rattling noise from the timing chain. So I thought that I would try and change the tensioner. The old one came out quite easily, but was in three pieces, the housing, the spring and i had to get the plunger out with a magnet. I put the new one in, but it was very easy to screw in until the last 2-3 millimeters, which is when I required the ratchet to finish it off. So, it is my understanding that they shouldn't be that easy to put in. I checked by putting a bar in to the hole and was able to apply a small amount of pressure and thus movement in whatever the tensioner presses against. I am now somewhat worried about starting it up and I am getting the chain replaced as soon as my mechanic has the time. Bottom line, has someone else changed theirs and was the experience significantly different from mine? Any help would be greatly appreciated.

I probably ought to point out that it is a 2011 200thp with 148,000 km. My mechanic thinks that it must have had the chain replaced at least once in its life, otherwise it is unlikely it would have achieved that mileage on the original chain. however, I have no idea if it has or hasn't been replaced at some time.

I have changed my tensioner as the old one was leaking oil out around the washer. If yours didn't come out in one piece then it sounds like it was shot to bits and your lucky you caught it in time. I locked the engine via the top hole on the gear box bell housing with a locking tool. Its a bit awkward to get at though. A stubby ratchet is the best thing to remove and tighten the Tensioner back up with. Plus remove as much pipe work as possible around it. I took out the hoist hook, the inlet manifold pipe from the intercooler and the sound enhancing pipes. You can also check the plastic timing chain guides by removing the rocker cover. They should all be as fitted if there is any wear on the top guide or cracks in it then the chain has come into harsher contact than normal due to Tensioner not doing its job.

 

[Calibrazxr750]

I have changed my tensioner as the old one was leaking oil out around the washer. If yours didn't come out in one piece then it sounds like it was shot to bits and your lucky you caught it in time. I locked the engine via the top hole on the gear box bell housing with a locking tool. Its a bit awkward to get at though. A stubby ratchet is the best thing to remove and tighten the Tensioner back up with. Plus remove as much pipe work as possible around it. I took out the hoist hook, the inlet manifold pipe from the intercooler and the sound enhancing pipes. You can also check the plastic timing chain guides by removing the rocker cover. They should all be as fitted if there is any wear on the top guide or cracks in it then the chain has come into harsher contact than normal due to Tensioner not doing its job.

I managed to get enough room by removing most of what you mention, but the long plastic tube that goes over the left side of the engine, I was only able to reove the two screws holding it in place and the rubber hose at the front. I couldn't really see how to remove it completely and it looked as though it would be a nightmare to put back again afterwards, so I just pushed it to one side. How do I remove it completely, so that I can remove the rocker cover?

 

[Jumper]

I managed to get enough room by removing most of what you mention, but the long plastic tube that goes over the left side of the engine, I was only able to reove the two screws holding it in place and the rubber hose at the front. I couldn't really see how to remove it completely and it looked as though it would be a nightmare to put back again afterwards, so I just pushed it to one side. How do I remove it completely, so that I can remove the rocker cover?

I used a 8mm ratchet ring spanner its the only way I could find to get at it from above. Reach right down the back of the engine with the spanner and you will feel a circlip around the hose with an 8mm head. TBH it comes off pretty easy once you get the clip off just pull and twist it. To get it back on spray some WD 40 on the hose to force it back on. The job is a whole lot easier with that huge pipe out of the way. I replaced the VVT solenoid while all that stuff was out of the way because believe it or not that was leaking oil as well all down the back of the engine!! Anyway that was 2020 and it was all worth it. No more oil leaks and the car runs better and idles a lot smoother now.

 

[Calibrazxr750]

Very good points. I already replaced the front VVT sensor and as I bought a pair, I would be foolish not to replace the other one while I am there. I will try and see if I can get a spanner down there, but I have rather fat hands.