The belt just went slack again. I thought maybe the tensioner bracket bolt repair had failed or something but I would have been surprised as a helicoiled aluminium bracket is much stronger than just a thread in parent metal.
On closer inspection it just seems as the tensioner spring had passed over top dead centre again but nothing broken. So I levered the tensioner bracket back towards its correct position and it popped back into position easily. Too easily if anything so I think the spring is getting tired.
I'll get a replacement spring.
Showing posts with label Ancilliaries. Show all posts
Showing posts with label Ancilliaries. Show all posts
Sunday, 21 November 2010
Wednesday, 13 October 2010
188,684 Miles
Had a bit of a problem with ancillary belt drive the other day (2010-10-01). I started the car to go home and there was a bit of a rattling, clunky noise coming from the engine sounding like something was loose. On closer inspection, the ancillary belt was flapping around quite a lot. I stopped the engine and had a closer look and there was an awful lot of slack in the belt. Just as well I decided to have a look as it wasn't driving the pulleys properly and I was about to go on the motorway. This belt drives the alternator, power steering pump and water pump (which in turn is connected to the radiator fan via a viscous coupling). So I would have either ran the battery flat, over heated the engine or most likely both.
At first it looked like I had completely lost a tensioner or idler wheel. There appeared to be a blank boss which looked like it was where a belt should be. But after some research (see image of belt run below) it was apparent that this was just the centre pivot of an 'L' bracket (1 in diagram), which is used to pivot the tensioner pulley into the belt lower down.
Feeling lower down to where the pulley should be, I immediately found the bolt that holds the pulley to the bracket was hanging out! I could just grab it with my finger and pull it out. The threads on the end of the bolt were full of aluminium and so it had obviously stripped the hole it was screwed into. This hole is in the 'L' bracket.
Initial reaction was that I was going to have to replace the bracket, which I REALLY did not want to do as it would obviously be a BMW only part being a small casting. This would of course equal 3 figure amounts of GBP.
So to determine what was going to be required I stripped out the bracket to inspect it closer. This was easily done, with the exception of requiring a 17mm hex key, which is pretty big and not normally in most tool kits. Luckily, where I work, I was able to find one. This was required to slacken the large boss in the centre of the 'L' bracket.
Brief procedure for removing 'L' bracket:
Once the bits were out it was indeed obvious that the problem was that the bolt had stripped the thread out of the bracket. Its hardly surprising as there is only about 1.5D of thread depth which is not a lot at all for aluminium. Even though it is not under any axial loading, like I said it needs to be removed every time the ancillary belt is replaced, so it is easy to imagine when the belt has been replaced in the past that someone has probably just done the bolt up too tight.
The pulley itself and everything else all seemed to be perfectly in tact. One thing that was worth noting was that the 'L' bracket, when in situ, had managed to pivot itself past its top dead centre with the spring so that it was fully pivoting the wrong way. this must have been as a result of snatching the loose belt and this is why there was so much play in the belt.
So now all that I had to do was repair the stripped hole in the 'L' bracket, which was a straight forward Heli-Coil operation. This was the first time I had used a Heli-Coil myself and I was very impressed at how easy it was and how simple yet effective it is. It saved throwing the 'L' bracket away just because of one damaged hole.
The upshot of this simple fix was also NO COST, as if I had taken it to a garage I would have been charged several hours of labour time and no doubt their solution would have been to tell me that the 'fa-lan-gee' was broken and just gone to BMW and ordered a new 'L' bracket, which I dread to think how much it would cost as its definitely a BMW only part, which = license to print money! Either that or they would tell me that's what was needed, charge me accordingly, then just Heli-Coil it anyway.
Either way I reckon I saved a minimum 300 GBP.
Refit was, as very often, reversal of removal... and the engine started and has been running fine since.
At first it looked like I had completely lost a tensioner or idler wheel. There appeared to be a blank boss which looked like it was where a belt should be. But after some research (see image of belt run below) it was apparent that this was just the centre pivot of an 'L' bracket (1 in diagram), which is used to pivot the tensioner pulley into the belt lower down.
Feeling lower down to where the pulley should be, I immediately found the bolt that holds the pulley to the bracket was hanging out! I could just grab it with my finger and pull it out. The threads on the end of the bolt were full of aluminium and so it had obviously stripped the hole it was screwed into. This hole is in the 'L' bracket.
Initial reaction was that I was going to have to replace the bracket, which I REALLY did not want to do as it would obviously be a BMW only part being a small casting. This would of course equal 3 figure amounts of GBP.
So to determine what was going to be required I stripped out the bracket to inspect it closer. This was easily done, with the exception of requiring a 17mm hex key, which is pretty big and not normally in most tool kits. Luckily, where I work, I was able to find one. This was required to slacken the large boss in the centre of the 'L' bracket.
Brief procedure for removing 'L' bracket:
- Remove radiator cowling - 2 plastic pop rivets at top.
- Remove front section of engine top cover - three cap head bolts.
- *Remove tensioner pulley bolt (already out on mine).
- With tensioner pulley bolt out the pulley itself will be free to come out.
- At this stage make a good note of the belt run. I managed to keep the belt in place. See image.
- Remove bolts at either end of tensioner spring and remove spring (both ends required as bracket + spring wouldn't come out past pipe work).
- Remove large central pivot bush with 17mm hex key (once slackened, easy to remove by hand).
- Remove 'L' bracket.
Once the bits were out it was indeed obvious that the problem was that the bolt had stripped the thread out of the bracket. Its hardly surprising as there is only about 1.5D of thread depth which is not a lot at all for aluminium. Even though it is not under any axial loading, like I said it needs to be removed every time the ancillary belt is replaced, so it is easy to imagine when the belt has been replaced in the past that someone has probably just done the bolt up too tight.
The pulley itself and everything else all seemed to be perfectly in tact. One thing that was worth noting was that the 'L' bracket, when in situ, had managed to pivot itself past its top dead centre with the spring so that it was fully pivoting the wrong way. this must have been as a result of snatching the loose belt and this is why there was so much play in the belt.
So now all that I had to do was repair the stripped hole in the 'L' bracket, which was a straight forward Heli-Coil operation. This was the first time I had used a Heli-Coil myself and I was very impressed at how easy it was and how simple yet effective it is. It saved throwing the 'L' bracket away just because of one damaged hole.
The upshot of this simple fix was also NO COST, as if I had taken it to a garage I would have been charged several hours of labour time and no doubt their solution would have been to tell me that the 'fa-lan-gee' was broken and just gone to BMW and ordered a new 'L' bracket, which I dread to think how much it would cost as its definitely a BMW only part, which = license to print money! Either that or they would tell me that's what was needed, charge me accordingly, then just Heli-Coil it anyway.
Either way I reckon I saved a minimum 300 GBP.
Refit was, as very often, reversal of removal... and the engine started and has been running fine since.
Wednesday, 3 March 2010
168,570 Miles
Just the day I went on paternity leave, we were luckily just getting home when the car started making a very funny noise and I could feel it too. It was an awful rumbling noise accompanied by vibration from the engine being felt through the steering wheel. Not nice. I had grim thought when listening to it at first thinking, oh no maybe the crank bearings have gone, as it sounds like a horrible, low down, internal knocking noise.
As I had just started paternity leave I luckily didn't need to go to work, so the next day I limped to the garage and asked someone to have a quick look. The very helpful people at TS Motors, Watford, had a quick look and spotted the obvious that the water pump had gone. The symptom being the rad fan, which is mounted to the pump on the front of the engine via a viscous coupling, was wobbling all over the place.
I was quite surprised, but also relieved, but the thought that the water pump had gone didn't cross my mind initially as the system had not lost any water. Usually, if the bearing fail in the pump, it tends to dump all its water in one go and you over heat. So I was surprised this had not happened. Anyway, looking at it, it was obvious as the fan was just flopping about, I knew the part wouldn't be too expensive, just a labour intensive job, i.e. lots of labour charge.
I would ordinarily do a job like this myself at home, but seeing as we had just had a new baby, it was not really convenient, so I booked it in to the garage to have the work done.
Whilst in the garage, I wanted them to do a few other jobs, seeing as it would be on the ramps. I needed to change the glow plugs, as the engine was becoming very reluctant to start, cranking for 30 seconds plus easily to get started. The cold winter had finally taken its toll and killed them off. The poor starting was becoming a major problem, especially when leaving for work at 0630 when all is quiet and then there's me cranking for a minute!
Also, unfortunately, I suspected the lower front control arm bushes had gone again. I could easily shove the front of the wheel inwards and see the bush flexing far too much. The car had not been handling brilliantly even after changing all the control arms only 2 months earlier. I think it is down to one of two things: Either I fitted them incorrectly or the components were inferior/faulty.
The only way I could think I fitted them wrong was if they were super sensitive to being tightened up with the arms in the correct orientation. You are supposed to tighten the bolt through the bushes with the arms positioned as if the car is at rest on its wheels on the ground, so that in most situation, the bush is not twisted, only temporarily with movement away from the rest position of the suspension. I tightened mine up with the hub jacked up, not literally with the wheels on the ground, so I could only think the angle was not quite right, but I find it very difficult to believe this would cause the bush to fail within two months.
The other idea is inferior or faulty components. I doubt they were faulty. Its possible but very unlikely really. So perhaps inferior. These were the cheapest option arms I could find, only 20 GBP each. I am sure I had read somewhere someone saying that you should really use OEM parts, like Lemforder, other wise cheaper alternatives will just fail quickly and end up costing you more in the long run. I will let the garage choose whatever arms they like and see how it goes.
So all in all, water pump, glow plugs and lower front control arms replaced, in a day's work. Wasn't too costly either, although 90% of it was labour, as usual, which makes me a bit sick knowing I could do it for free. But it was convenient to be free for a day instead of tied up outside with the car.
Got the car back and it starts on the dot, even when cold (very nice!), obviously no more noise from the water pump and handling seems.... better, still not perfect but better. Still things to investigate in that area I think.
Also on my to do list....
Side note... fitted some new interior lights as the ones I had were very basic, as in no map reading lights and no switches at all on the rear ones for someone to turn it on in the back to read. So I got some new ones from someone breaking a 535i which had individual map spot lights and switches in all four positions.
As I had just started paternity leave I luckily didn't need to go to work, so the next day I limped to the garage and asked someone to have a quick look. The very helpful people at TS Motors, Watford, had a quick look and spotted the obvious that the water pump had gone. The symptom being the rad fan, which is mounted to the pump on the front of the engine via a viscous coupling, was wobbling all over the place.
I was quite surprised, but also relieved, but the thought that the water pump had gone didn't cross my mind initially as the system had not lost any water. Usually, if the bearing fail in the pump, it tends to dump all its water in one go and you over heat. So I was surprised this had not happened. Anyway, looking at it, it was obvious as the fan was just flopping about, I knew the part wouldn't be too expensive, just a labour intensive job, i.e. lots of labour charge.
I would ordinarily do a job like this myself at home, but seeing as we had just had a new baby, it was not really convenient, so I booked it in to the garage to have the work done.
Whilst in the garage, I wanted them to do a few other jobs, seeing as it would be on the ramps. I needed to change the glow plugs, as the engine was becoming very reluctant to start, cranking for 30 seconds plus easily to get started. The cold winter had finally taken its toll and killed them off. The poor starting was becoming a major problem, especially when leaving for work at 0630 when all is quiet and then there's me cranking for a minute!
Also, unfortunately, I suspected the lower front control arm bushes had gone again. I could easily shove the front of the wheel inwards and see the bush flexing far too much. The car had not been handling brilliantly even after changing all the control arms only 2 months earlier. I think it is down to one of two things: Either I fitted them incorrectly or the components were inferior/faulty.
The only way I could think I fitted them wrong was if they were super sensitive to being tightened up with the arms in the correct orientation. You are supposed to tighten the bolt through the bushes with the arms positioned as if the car is at rest on its wheels on the ground, so that in most situation, the bush is not twisted, only temporarily with movement away from the rest position of the suspension. I tightened mine up with the hub jacked up, not literally with the wheels on the ground, so I could only think the angle was not quite right, but I find it very difficult to believe this would cause the bush to fail within two months.
The other idea is inferior or faulty components. I doubt they were faulty. Its possible but very unlikely really. So perhaps inferior. These were the cheapest option arms I could find, only 20 GBP each. I am sure I had read somewhere someone saying that you should really use OEM parts, like Lemforder, other wise cheaper alternatives will just fail quickly and end up costing you more in the long run. I will let the garage choose whatever arms they like and see how it goes.
So all in all, water pump, glow plugs and lower front control arms replaced, in a day's work. Wasn't too costly either, although 90% of it was labour, as usual, which makes me a bit sick knowing I could do it for free. But it was convenient to be free for a day instead of tied up outside with the car.
Got the car back and it starts on the dot, even when cold (very nice!), obviously no more noise from the water pump and handling seems.... better, still not perfect but better. Still things to investigate in that area I think.
Also on my to do list....
- Tailgate gas struts all needed replacing.
- Air/con not working
- Heater still giving me hot air only
Side note... fitted some new interior lights as the ones I had were very basic, as in no map reading lights and no switches at all on the rear ones for someone to turn it on in the back to read. So I got some new ones from someone breaking a 535i which had individual map spot lights and switches in all four positions.
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