Another Noise…. - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Homeboy981 · 05-13-2013, 07:09 AM

I am getting a "loose nut" sound when I coast. No…not me!

When in gear I cannot hear anything but exhaust sound. When the vehicle is out of gear (in neutral and coasting) it sounds like the transmission has a noise once in a while that sounds like a 'marble in a can' only for an 1 second or so. I observed the noise becoming more frequent and parked the car.

To shed more light on cause I have recently been down a dirt road…that was being re-surfaced, so it was DOUBLE dirt and gravel - my car was a mess AND I recently put on a clutch/LWFW combination.

Someone suggested they have had the LWFW pressure plate loosen on them. What would that sound like when the bolts let go?

I have not driven car for a couple days since it made that unnerving noise. I was planning on going back to pull the transmission and clutch….unless someone has a better idea, he said hopefully.

Are there specific places that may catch rocks around the tranny or something else that I can check?

Flavor 987S · 05-13-2013, 09:08 AM

Well, a LWFW will be more noisey vs the stock set-up. So, it could be normal. But I would not describe the normal louder LWFW sound "as a marble in a can". Can you post an audio clip?

woodsman · 05-13-2013, 12:08 PM

I found 2 loose bolts on my pressure plate but also another for the flywh pos sensor was loose and they never made any noise but the fingers were then working unevenly and this caused the release bearing to break off it's mounting clips and then strange clutch behavior began over 4000 RPM.
With the single-mass flywh there is gear rattling from the gearbox and can be heard from within the car only in a quiet environment while idling, or while standing at the back of the car. I'm not sure if that's what your hearing but it may be premature to tear out the tranny just yet. There's others who can add more than I can but let the scientific inquiry take its course Homeboy!

Homeboy981 · 05-14-2013, 05:24 AM

First off, thanks for the replies.

The 'strange' noise is OVER and ABOVE the normal "dieseling sounds" the LWFW makes at idle. I first noticed it between shifts, then I tried coasting without being in gear, and now I have more evidence.

I was hoping for a rock but I started the car yesterday and heard the noise at idle. I would record it but the noise is un-nerving!

Looks like I'm going in.

Prepare the patient for surgery!

JAAY · 05-14-2013, 05:46 AM

How old is your flywheel that is in there now? The Dual mass when it goes is noisy as hell . mine is shot right now and shakes like a mofo. I am actually not driving mine right now till I do a clutch job.

JAAY · 05-14-2013, 05:50 AM

Nevermind.. Just saw you have an aasco.

cameronzero · 05-16-2013, 10:09 AM

i know in the miata's that the sound you're describing comes from worn bearings in the water pump and alternator, especially when the belt is either too loose or too tight. they can also come from the crank if the rotating assembly isn't balanced (using the stock crank pulley on the 1.6) and you stay high in the RPM range. factory redline is 7.2 (1.6) and after the LWFW a good amount of people will go 8k+ with cams and dual spring valves.

did you balance your whole rotating assembly before instilling the LWFW on the boxster? i read that installing a LWFW in place of a dual mass without a balance can lead to catastrophic engine failure due to the vibration negating effect of the dual mass fly wheel. also, since both the pressure plate and LWFW are not factory, it's safe to assume that the factory manual will not cover them. go by what the manufacturer recommends when installing their parts, as i would hope (hope being the main point here) that they did actual product testing on the applied parts with the vehicles they are selling them for. as some parts can be pretty universal, it could be possible that the manufacturers recommendations will not suit your set up.

woodsman · 05-16-2013, 12:27 PM

hey Homeboy, I wonder if the tranny's already been apart on that car and was never repaired properly? How many miles did you drive it before taking everything apart ? I find it hard to believe a bolt YOU tightened could already come loose. I listened to your video and really couldn't decipher any of the sounds. At least it'll come apart easy. I'm sure Aasco calls for loc-tite only on the flywheel bolts and there's a mismatch of metals to consider when bolting the p p down ( long - term oxidation) and this isn't the case with a dualmass but I decided to loc tite the pp too- major bummer for you whatever the prob is!

Homeboy981 · 05-17-2013, 05:46 AM

Quote:

Originally Posted by woodsman

hey Homeboy, I wonder if the tranny's already been apart on that car and was never repaired properly? How many miles did you drive it before taking everything apart ? I find it hard to believe a bolt YOU tightened could already come loose.

Yep. I tightened it. How did you know I have a tendency to 'over-torque'? That's what I get for relying on a torque wrench…beats a stripped bolt I guess!

I made it almost 1,000 blissful miles. Just enough to be left wanting. The speed and sound of all the cumulative mods is certainly intoxicating.

Here's hoping it is minor.

But, for now, she will remain parked - while I make a living! Those houses don't buy themselves!

woodsman · 05-17-2013, 10:00 AM

houses be dammed, get 'er ass up and get in there man!

Homeboy981 · 05-22-2013, 07:59 AM

Just to update…got the engine torn down to the point of RMS replacement. Thought I would find an improperly-torqued bolt.

Took it all apart. The transmission is out and dry with some dust, not bad. ALL the bolts were tight to spec. No exhaust shield rattles. No muffler noises. 02 sensors & header bolts are tight. LWFW was stuck on there like glue too. No slippage in the pressure plate bolts either. Water pump has 8k miles on it.

Was it all for naught?

Things to still check:
* Spark Plugs
* Header Bolt Torques
* RSS Pulley - though I doubt it
* Oil Filter for metal pieces

The starter motor (see pic). The shaft had a little 'play' or 'wiggle room' in it, is that normal?

I implore you...Can ANYONE possibly suggest something else to check & help a Boxster guy out?

Thank you in advance.

Signed,
Stuck In The Slow Lane

BruceH · 05-22-2013, 10:03 AM

I feel for you Mark! Wish I had an idea. Good luck!

Perfectlap · 05-22-2013, 10:20 AM

Have you tried posting on RennTech?

EssexPorsche · 05-22-2013, 11:00 AM

Ok- so it was doing in gear and coasting but not rythmical nor rev dependant.
I would suggest the diff, but I assume from the clip the car was stationary... It's rather like the tranny but I'm starting to discount that as well if was still there and stationary.

It takes me back to the crankcase.
Have you checked the cylinder head bolt and the oil scavenger pumps- both throw bolts that can end up in the oil ciculation.

Well to be more precise the cylinder head can, which can then bust the scavenger pumps which can the throw chunks into the lubrication system?

Drop the sump (pan) and have a look?
I'm hoping for a happy ending.

EP.

woodsman · 05-22-2013, 11:11 AM

many, many lwfw's have been sold and used by Porsche owners without problems. the owner of Aasco has been interviewed by Excellence mag. and has been in the Porsche business for something like 40 yrs. You can call him and actually talk to the man himself (like I did), unlike most 'vendors', today. He IS the mfg.
I can't see why you'd need the tranny in , to run engine as long as you have the fw and crank sensor in????? Also ,I wonder if there's an easy way to open up the trans.? How about physically rolling it over, carefully, on the lawn (after draining oil) and listening close for something loose ? Stand it up on the bellhousing etc. But then you said the problem got worse and fast so it could be a disintegrating bearing- I too, feel your pain Homeboy- hope it's a simple fix for ya'

EssexPorsche · 05-22-2013, 11:33 AM

Woody,
Apologise if I offended anyone re LWFW, was just relaying what I have read.
It was not based on personal experience so in hindsight perhaps I should not have mentioned it without foundation.

I was just trying to give Homeboy other avenues of investigation given that he was drawing a blank.

I'll stay subscribed to see the outcome but won't post anymore on this as I am no a porsche mechanic.

Good luck guys.

woodsman · 05-23-2013, 11:56 AM

Understood ESSEX. It's so easy to relay and so difficult to investigate- for all of us.

Homeboy981 · 05-23-2013, 12:12 PM

First, guys thanks for the insight and responses.

I was moving the transmission around today…to get it out of the way and get into the freezer (which is not a Porsche so it still runs). I noticed that the tranny housing made a loud 'ding' noise. A thought said, "Where have I heard that noise?"

I rocked the transmission again and it made a noise, another 'ding'. I then shook it violently - to simulate the action of a LWFW and it sounded like a bunch of marbles in a can!

It is the clutch release lever mechanism hitting up against the housing. Who picked that? Next question, what is supposed to stop the lever from slapping the housing like that? This is a little more than I bargained for with a LWFW. Too many things vibrating cannot be good. Pity! The driving part of the LWFW WAS GOOD!

Now to confirm my suspicions….I need to start the car. You guys sure I can start the car without the transmission attached? It looks so naked!