[myculito]

My 335d has 55K miles.

All has been normal. Stopped into a supermarket, get a battery icon on the dash, loss of powering steering, and what smells like burning tires.

Car is inside my garage now. What I notice is that the serpentine belt doesn't appear to be moving. It's in tact (belt was replaced at 35K miles), but looks like it's struggling to move, as noticed by staring at one of the upper pulleys connected to the serpentine belt.

What the hell is going on?

[CO335D]

It's your crankshaft pulley. Pretty common failure on these cars. Search this forum and you'll find plenty to read up on. It isn't a terrible job to fix, but you'll need a tow either way. I wouldn't drive the car.

[myculito]

It's at my home garage, I don't plan on driving it anymore.

Is this an expensive dealer repair? Am I better off DIY'ing it?

[335dsl]

Wow, 55k miles and it goes kaput! It'll set you back a few hundred bucks. Try to get a Febi Harmonic Balancer. I was told Vaico is no good.

[myculito]

ECS tuning has a kit with everything. https://www.ecstuning.com/b-assemble...11238511371kt/

Do I need this kit, or do I just need the crankshaft pulley?

[335dsl]

Here's the diy and you also got the parts needed for the job.

http://www.e90post.com/forums/showth...monic+balancer

[335dsl]

Originally Posted by myculito

ECS tuning has a kit with everything. https://www.ecstuning.com/b-assemble...11238511371kt/

Do I need this kit, or do I just need the crankshaft pulley?

Usually, people just get the pulley (aka harmonic balancer), serp/AC belt and (4)bolts. Unless, you really need the other parts then get them.

[myculito]

335dsl thanks for the help so far. I went ahead and purchased the full kit from ECS, and will just replace that crap as part of preventative maintenance.

Have you done this job before? I'm trying to read the DIY from Mik325tds, but i'm struggling to follow his additional tips regarding the fan cowl removal.

[Torqu3]

There's is literally a sticky post dedicated to this kind of thing.

[PerfectAce]

Originally Posted by myculito

335dsl thanks for the help so far. I went ahead and purchased the full kit from ECS, and will just replace that crap as part of preventative maintenance.

Have you done this job before? I'm trying to read the DIY from Mik325tds, but i'm struggling to follow his additional tips regarding the fan cowl removal.

There's nothing too complicated about the fan shroud removal -- it should all seem logical to you once you get under the hood and spot 1) the fasteners holding it in place and 2) the bits in the way that are preventing it from being pulled out cleanly. It's definitely possible just to unclip and move stuff out of the way, but I found that pulling the clips out of the fan shroud helped considerably by eliminating snag points. (The clips are just held in with xmas tree fasteners and can be pried loose.)

I predict that the other thing that will give you trouble is the A/C belt installation. I made multiple attempts using a stretch belt tool and just could not get the 824mm to go on. I gave up and just re-installed the old 830mm belt. If you manage to get the 824mm belt on, let us know how you did it -- I'm not the only one here that had trouble with it.

[OmahaDZL]

Originally Posted by 335dsl

Wow, 55k miles and it goes kaput! It'll set you back a few hundred bucks. Try to get a Febi Harmonic Balancer. I was told Vaico is no good.

BB_cuda

This is leading me down a path to say that calendar age might be significant determinant .... Maybe the rubber breaks down and is just inevitable regardless of miles or HP/TQ numbers.....It could also play into the climate....the rubber would break down less in colder climates, right? ...Dr Thermodynamics .... what do you think?

[myculito]

Originally Posted by OmahaDZL

BB_cuda

This is leading me down a path to say that calendar age might be significant determinant .... Maybe the rubber breaks down and is just inevitable regardless of miles or HP/TQ numbers.....It could also play into the climate....the rubber would break down less in colder climates, right? ...Dr Thermodynamics .... what do you think?

I'm in Miami, and my AC is always on... may be a worthwhile factor to point out.

Upon closer inspection this morning, I can confirm that the crankshaft pulley has taken a shit.

There are rubber chunks sitting on the pulley.

[myculito]

Originally Posted by PerfectAce

There's nothing too complicated about the fan shroud removal -- it should all seem logical to you once you get under the hood and spot 1) the fasteners holding it in place and 2) the bits in the way that are preventing it from being pulled out cleanly. It's definitely possible just to unclip and move stuff out of the way, but I found that pulling the clips out of the fan shroud helped considerably by eliminating snag points. (The clips are just held in with xmas tree fasteners and can be pried loose.)

I predict that the other thing that will give you trouble is the A/C belt installation. I made multiple attempts using a stretch belt tool and just could not get the 824mm to go on. I gave up and just re-installed the old 830mm belt. If you manage to get the 824mm belt on, let us know how you did it -- I'm not the only one here that had trouble with it.

Hey, thanks for the clarification, I'll take another look tonight when I get home for those clips.

I bought the new AC belt from ECS, and I already have the Lisle belt tool. I'll let you know if I have any issues.

[335dlci]

The ast tool is the best tool on the market for the belt.

[myculito]

So, did the job last night. Wasn't too bad.

Here are the pictures of what my pulley looked like. Again, car is around 55-56K miles.

[BB_cuda]

Originally Posted by OmahaDZL

BB_cuda

This is leading me down a path to say that calendar age might be significant determinant .... Maybe the rubber breaks down and is just inevitable regardless of miles or HP/TQ numbers.....It could also play into the climate....the rubber would break down less in colder climates, right? ...Dr Thermodynamics .... what do you think?

This whole HB going up in toast is so wierd. I've got other vehicles with decent power and never tear these things up. Perhaps this one just has a whole lot more damping going on and perhaps thus is sacrificial.

Not a Dr as in not a PhD but versed specifically in heat transfer. My take is abuse of a part is the the the time integral of heat and torsional load. That means it's a combo of the loading and heat over the service life. Omaha knows this failure heee is right in my backyard mileage wise. I just crossed over 58,000. I still see this on the minus 1 sigma side of the failure population. PR is another 51,000 mile failure. He was tuned (where the heck has he been by the way). I've been running tuned for 26,000 miles and 3 years. Time will tell and you guys will hear if/when my number comes up.

[Asonchadwick]

Originally Posted by PerfectAce

There's nothing too complicated about the fan shroud removal -- it should all seem logical to you once you get under the hood and spot 1) the fasteners holding it in place and 2) the bits in the way that are preventing it from being pulled out cleanly. It's definitely possible just to unclip and move stuff out of the way, but I found that pulling the clips out of the fan shroud helped considerably by eliminating snag points. (The clips are just held in with xmas tree fasteners and can be pried loose.)

I predict that the other thing that will give you trouble is the A/C belt installation. I made multiple attempts using a stretch belt tool and just could not get the 824mm to go on. I gave up and just re-installed the old 830mm belt. If you manage to get the 824mm belt on, let us know how you did it -- I'm not the only one here that had trouble with it.

I had issues getting mine on where I only got 2 grooves on as i did not know one came off lol. So ultimately i had to use the tool on the a.c. compressor to keep the grooves on and it wasn't easy. I have the lisle tool. Another hand would have made it easy though just need to keep the belt on the ac compressor.

[Miko226]

Harmonic Balancer dead.

[PerfectAce]

Originally Posted by BB_cuda

This whole HB going up in toast is so wierd. I've got other vehicles with decent power and never tear these things up. Perhaps this one just has a whole lot more damping going on and perhaps thus is sacrificial.

Not a Dr as in not a PhD but versed specifically in heat transfer. My take is abuse of a part is the the the time integral of heat and torsional load. That means it's a combo of the loading and heat over the service life. Omaha knows this failure heee is right in my backyard mileage wise. I just crossed over 58,000. I still see this on the minus 1 sigma side of the failure population. PR is another 51,000 mile failure. He was tuned (where the heck has he been by the way). I've been running tuned for 26,000 miles and 3 years. Time will tell and you guys will hear if/when my number comes up.

I was spitballing with an BMW tech a couple weeks ago about this very issue and he speculated that the type of alternator may play a role. I don't know enough about the M57 yet to know if this is right or not, but it was his recollection that the M57 has a fixed-pulley alternator (does it?) and as a result may be subjecting the rubber damper to serious torsional forces that when combined with other factors (heat, rubber decay, etc?) weakens the part to the point of failure. He wondered if installation of an overrunning alternator pulley might be beneficial in regards to the lifespan of the HB.

I don't know enough about these things to opine, but figured you and others here are knowledgeable enough to offer a more informed opinion. Thoughts?

[Thecastle]

AS to why these particular harmonic balancers fail so early is a matter of speculation. I'm also seeing failures becoming increasingly common on the S63's as well.

The major factors that seem to determine wear on these from what I can tell, are age, heat, oxygen and ozone exposure which degrades the rubber. Of course also the amount of time spent at idle as my understanding the M57 places its greatest harmonic load on the balancer at idle. But Ozone exposure really seems to be a major factor in the rubbers degradation. Plus heck these cars are all old now. No one expects tires to last more than 5 years when exposed to the environment, its probably not unexpected that these are failing as the youngest cars are approaching 7 years old.

I'm at 61K miles and mine is visibly cracked. I plan to replace my HB as soon as the weather cools down here.

[BB_cuda]

Castle, this one is reeaaalll close to home. We are both in same gulf coast envt and he only has 3000 more miles.😕

[Torqu3]

Originally Posted by BB_cuda

Castle, this one is reeaaalll close to home. We are both in same gulf coast envt and he only has 3000 more miles.😕

My October 2009 build date, MY 2010 335d spent its life in downtown Houston. I bought it at 70,771, drove it 150 miles home, and it failed. Right at 71k. So, be prepared. The day is coming, but the fluidampr is coming too.