Hiya NAM,

Posted this in a similar thread, but it was suggested I start a new one:

Guys: long-time lurker, first-time poster here. First off, thanks for all the info I've gotten from this site over the past year of R53 ownership.

I've got an '05 R53 with 115k miles that began making the rattle very suddenly the other day. I started to put it into front end service mode fully expecting this to be a supercharger/water pump issue (there a few other threads addressing this on NAM), but was surprised to see the harmonic balancer all torn up (see photo). The HB was replaced less than a year ago, and I replaced the serpentine belt about 350mi ago...no issue with the HB at that point.




[I]harmonic balancer after < 4k miles[I]

Now I'm seeing that sandplasma's issue was actually a seized alternator, which would make more sense to me seeing as how at least the alternator and HB are running off the same belt. Here's what I'm wondering:

-Do any of you have experience with an HB failing after so short a time? This isn't the rubber inside...it's the steel housing on the outside.

-Would you augment anything from my planned course of action?
1) Inspect/replace alternator
2) Replace HB
3) inspect/oil supercharger and water pump
...while I'm in there...
4) Replace idler pulley
5) replace coolant, change oil
6) toss on some new brake pads

Also, while I'm inspecting the SC & WP, what are some telltale signs of wear? It's my understanding that rebuilding an SC effectively requires a machine shop, not a dude with a garage and some hand tools.

Thanks for your help!

 

holey cow! Daaaaammmnn.

I can't speak to the HB, other than the not so helpful "shoulda put an ATI on there when replacing it the first time"

As for the SC:
Yes. If you're going through the process of removing the SC, measure the volume of liquid removed from either side, and compare it to the fill quantities that you find listed in other threads.
Also, using a light, look into the fill holes and check the quality of the gearing and see if there are any metal particles.

BUT - the cost of a rebuilt SC is around $800-1000. Sending out yours for rebuilding is also an option. The thing is... they have a tendency to give you plenty of warning when they're going to fail (as they are failing). It's a helluvalota work to pull the SC if you're just doing it for fun. If you are counting/costing your hours it may be better to just leave well enough alone until it sounds like failure is happening and have one spare ready to put on if you're really worried.

 

Well, I'm deep into it now...whole front end is off the car, and I stopped just before taking off the SC (using ModMini's excellent tutorial). The alternator spins freely, so I've eliminated that as the culprit. Tomorrow evening I'll remove the SC and inspect.

Now Jamez, I totally get what you're saying about SCs giving a lot of warning, but this rattle is BAD. Like, so bad that when I went to take video of it to post, I decided to shut the car off instead for fear of something grenading. To be perfectly honest, I'm skeptical that any amount of lubrication is gonna fix that. But I'll give it a shot and update with pics.

 

If the crank pulley broke steel sounds like you have bigger issues than a supercharger replacement.

 

Have you heard of this happening? If so, what caused it?

 

+1 to what bavmotors said


Honestly, I can't say I've ever seen anyone post a HB like what you've shown. It's always been the rubber failure on old HB's

 

I didn't find your other post before making my first comment about the SC.
yes, if the SC is the culprit and making that sound you will most certainly see the evidence when you take the water pump side drain plug out.

After you sort out your HB replacement (could the part be under a warranty from where you bought it?) then dive into that SC

 

This is a pretty random observation ... To me, it doesn't look like the steel in the damper failed by the applied torque (such as the engine trying to drive a siezed alternator). It looks more like the three legs failed by flexing, which would happen if the damper pulley wasn't lined up with the other pulleys in the system - bad design, not seated fully, or maybe even the thrust bearing on the crank is gone.

 

One observation ....
The motor can be run momentarily with the belt off....no waterpump, but with a cast-iron blocks, about 30 seconds is ok...and even if the cooling system is open, a few seconds should be OK...
I would want to know 100% that the engine is not in its DEATH throes ...with a failed internal parts causing a huge imbalance....
Tearing steel is huge....
Just a guess...the rubber and the outer ring survived...so the drive imbalance did not come from bad accessories.....the rubber and fabric belt would have snapped a long time before STEEL would have fatigued...let's face it..belts are pretty good...but unless the crank damper is of pretty terrible quality, I seriously doubt it failed cuse of a tourque force applied by a rubber belt .
Think the crank was wobbling at high-speed...fatigued the metal....and boom...
Hate to say it...the more I think about it...think the inside of the motor is toast...bearing gone... imbalance.. wobble...boom!!
Maybe a botched install could cause the carnage...not seated all the way or crooked....but still...wow!!

Before I spent any more $$ messing with a sc...I would look at the motor...
Hopefully a pro from Detroit tuned or another vendor pops in...
Hate to assume the worst...but when an engine starts to tear metal....
I know harmonics are a powerful force (anybody ever see "Galloping Gertie" the bridge out on the Pacific NW from years ago?), Even destroying bridges..https://en.m.wikipedia.org/wiki/Taco...s_Bridge_(1940)

 

Probably a good idea to drop the oil pan and inspect the bearings - especially the thrust bearing - for play. A couple of hours work, well worth before spending more

 

Ok, took me a couple days to find the time to do this, but the oil pan is off, and I don't see anything alarming. No metal shavings, bearing parts, etc. I should go one step further while I'm in there and inspect the bearings; how can I best achieve this?

I think it's important to note that I haven't spent a dime on this issue yet (aside from a set of bolt-grips to deal with a stubborn oil drain plug...those'll come in handy another time, I'm sure). I'm thinking if there aren't any red flags with the crankshaft bearings, the smart thing to do would be to change the SC oil while I'm in there, crank pos sensor o-ring, oil pan gasket (both leaking), new HB, then put the whole thing back together and see what's up with that noise.

 

Can you wiggle the crank...look for end play... typically the classic proof the engine has excess wear, and needs a rebuild...might make sense here...if the crank could move a bit...and the harmonic damper absorbed it...know my old OEM damper weighted a provider name ton....metal was sold...so that's why we are so surprised ...
Not sure what the spec is...but it's not much...
I guess it's always possible you got a bad damper...that's why I suggested you run it for a few seconds, no accessories... isolate your sound.

 

Gotcha, and thanks for the advice. I didn't feel any play in the crank...even had my girlfriend push the clutch in and out in case pressure on the flywheel had an effect on it, but it was solid. What I could see of the cylinder walls looked pretty good too. I'm going to replace the oil pan gasket (shot--real messy under there), replace the oil and filter, and run it for 30 seconds or under to see if the sound becomes more apparent. Really hope it's a shoddy damper.

 

I'm glad you didn't find a sump full of metal. That's a good sign! Take a good close look at the oil pickup and make sure there isn't debris stuck there.

You are right about the clutch - the springs will be pushing the crank against the thrust bearing from one direction. And those are some beefy springs! Very hard to measure the wear/play like this. Perhaps use a feeler gage on the slack side (away from the clutch) and assume most of the wear is on the side getting pressure from the clutch.

You can unbolt one (or more) of the connecting rod bearings and check for wear or just wiggle them and look for play. The connecting rods are the "freeze fracture" type, so it is imperative you put the mating halves back on the matching con rod, and in the original orientation.

 

Any discoloration of the bearings?
They tend to get streaks and change color when they have been overheated....
The outer layer, if intact, gives most bearings, an even color...
When worn, you see the different metals that make up the insides....the parts NOT intended to slide...
Since most MINI'S NEED AN OIL PAN GASKET, you are only out maybe $25....
When you reassemble it, I WOULD suggest you take off the valve cover....and look at the cam...the number 4 cam lobes seem to be the ones that get damaged the fastest, even in a low oil situation.
If gauled up you might need a cam and a lifter....
I'm only think this stuff cause maybe a prior owner.....
Again, it about a $5 part, and it might give us u the opportunity to swap out the seals on the sparkplugs...they tend to start leaking, letting oil get on the sparkplug threads....
Good too hear it's ok so far.
Then again....if stuff looks great...you could button it up...and say maybe a bad part or bad install..
You will know pretty fast....

 

+1 pull the cover off and look at it.

 

Guys, sorry for the radio silence for the past couple weeks...life got in the way of my wrenching

I took your advice and examined the cam lobes and crank bearings. All looked good, so while the car was apart I did the following:

-Replaced oil pan gasket
-Replaced crank position sensor o-ring
-Replaced SC oil
-Examined PTO gears from SC to water pump; looked great (oil seemed very fresh and plentiful too...seal must be in great shape).
-Replaced HB (not optional
-Fresh oil/oil filter and coolant (also not optional)
-Replaced front brake pads (why not?)

Valve cover gasket, spark plug tube o-rings, serpentine belt, air filter, and cabin air filter were all replaced within the last several hundred miles, and I'm happy to report that the car is all back together and running better than ever. I drove it 200 miles and it performed flawlessly. In the end I'm going to chalk up the noise to a defective HB, but am glad I got the chance to really dig into the MCS and give it the mid-life refresh it deserves!

I'd like to thank you all for your input. I really appreciate you taking the time to help me sort out my problem, as well as being able to access all the knowledge floating around this forum.

North American Motoring ROCKS!

 

That's great. You did a heroic amount of inspecting and maintenance. Hope you get many more miles for your efforts!

 

Great to hear it running good!!
Better yet hear there were no show stoppers....trying to think what could tear metal like that...ouch...most every idea I had got $$ pretty fast!

 

I only hope you got an ATI and not OEM again