front wheel bearings: I are confused

[aschen]

Warning a wall of text will apear below:


About a week ago I was headed to try to autocross my car for the first time since 2002. On the highway I heard a bit of a squeek from the front so I naturally assumed the wheel bearing were due for survice soon.


1/2 hour later as I am pulling into grid for autocross, I hear a loud Pop followd by very loud grinding from the front end at the wheel speed. I pulled out of grid and jacked up the front end. I couldent feel any play in the wheel in any direction. However the wierd part is the wheel would spin very smoothly and freely with just a small push, like there was no friction from the brakes. Perfectly smooth no noise. I put the car back down and drive a few feet and it sounds terrible metal on metal.

My non expert diagnosis was that a wheel bearing some how exploded and there was enough play in the bearings to open up the brakes and realse any standing friction. Keep in mind at this point I didnt even know how the bearing preload adjuster worked.

Fast forward 2 weeks I pulled the front hubs apart and all the parts look pristine. There was still tons of grease in there as well. Could it be that I just needed to tighten the main adjustor a bit? It definitely felt like a catastrophic failure though I heard a big "pop" and the grinding noises were not subtle.

Does anybody have any wisdom to share with me on this? I ordered all the parts from our host, but I would like to know what is going on before I start trying to press things in and out.

Thanks in advance,
Aaron

[afterburn 549]

"A"Arm arm squeak

[Reiver]

If you have sachs struts check that the strut cap is tight and not unwound.

[msterling]

Something stuck between the brake pad and the rotor.

[Ronnie's.930]

Maybe you have already tried this, but since the location of sounds can be very misleading, it would be a good idea to raise the rear and see if there is anything unusual going on when you spin the rear wheels.

[aschen]

Thanks guys but it was unmistakably from the front pass side and I was convinced it was directly related to wheel speed but now I am second guessing myself. It was a terrible screeching grinding so I'm really scratching my head. Any idea why the wheel would turn so easy and freely? I was thinking maybe the spindle nut was somehow loose

[RedCoupe]

I agree with MSTERLING that something may be wrong with the brake pads or rotors. I have actually had pads crack and bits of the pad jam between the pad and rotor, and this makes horrible noise. If you haven't already, I would inspect the pad, rotor and caliper closely.

[DRACO A5OG]

So let me ask you, when you heard the noise were you under 10PMH and slight braking when pulling up to the grid, going straight or turn/curve?.

Also did you or a mechanic service the bearings?

Jim

[aschen]

OK now my memory is failing me a bit but I was definitely going slow and likely turning. In fact I thought I hit a cone in grid from the pop. I don't think it is the pads as I have the caliper off right now and they seem fine. I took the hubs offby myself. The front bearings were adjusted by a professional porsche mechanic about 2 years ago which is less than 1000 miles probably. I

[targa44]

Well.... how about checking the inside rim of the wheel. Is it scratched/scraped? When under load you hear the noise and lifting the wheel, you don't? Does the car still sit level?

[NYNick]

Why don't you pull the hub and give it a shake? Maybe you'll hear stuff inside? At least inspect with a light.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

[Ronnie's.930]

Originally Posted by NYNick

Why don't you pull the hub and give it a shake? Maybe you'll hear stuff inside? At least inspect with a light.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

The OP said in the first post that he has taken the front hub assemblys apart and that everything looks good . . .

[DRACO A5OG]

Originally Posted by aschen

...I was definitely going slow and likely turning. In fact I thought I hit a cone in grid from the pop....The front bearings were adjusted by a professional porsche mechanic about 2 years ago which is less than 1000 miles probably...

Okay, so brakes are off the list, thank goodness.

I know you may be in a hurry ( I am guilty of this as well ) but please take your time to check your grammar and spelling. Even myself, I failed English in College so I too have to re-read everything I post publicly. This forum has an auto check for miss-spelled words by having a red squiggle line under those suspect words and a spell check feature too. It is helpful for the readers to understand you more clearly.

Okay, now you mentioned going slow and on a turn, This may be the culprit. What you heard is 99.9% certainly the rear wheel bearings, one or both ( does not matter you must replace in pairs in any case ). To test this, find a road with a gradual side berm, ( it will look like the road has a slight curved gradient up to the grass or side walk area ---\___/---- ) then drive only the passenger side wheels up on to that berm, slowly. I bet you will hear that pop again and or grinding, the grinding is the rear bearing resonating thru the car and it is giving you a feeling it is coming from the front but it really isn't. It took me several months to figure this out too. So I totally understand your confusion Brother.

Good to read it was a pro wrench serviced your car, it was not the dealer was it? If so you really need to check it yourself, especially if you are seriously planning on auto-crossing. Raise the front of the car safely and sit down in front of your wheel and grab firmly on the rubber at 2 o clock and 7 o clock, pull and push ( one direction on one hand and the other hand going the opposite direction ) very firmly and again at 10 o clock and 5 o clock. I am a bit concerned when you wrote it moved freely, there should have been a bit of resistance within 3-5 seconds of rotation by hand.

Now take the wheels off and check the struts, grab the top portion in the middle and lower portion in the middle and start pulling and pushing. Also check the way bar bushings, tie rod ends and ball joints for abnormal wear or metal to metal contact evidence.

Hope that helps and sorry about the grammar thing, all these gentlemen have been very nice but you have been very lucky no one has flamed you yet on this.

Let us know what you find,

Jim

P.S. do you have stock ( OEM ) wheels or are the upgraded or added spacers?

[Trackrash]

When I turn my steering wheel all the way to its stop, with my 225 autocross tires mounted, it makes a horrendous scraping noise. My tire is rubbing on the inner fender well. Could that be your problem as well?

[DRACO A5OG]

I guess we need to read about his set up first :-)

84 930, as long as he did not dump it and added huge aftermarket wheels and tires.

[Ronnie's.930]

Originally Posted by DRACO A5OG

I know you may be in a hurry ( I am guilty of this as well ) but please take your time to check your grammar and spelling. Even myself, I failed English in College so I too have to re-read everything I post publicly. This forum has an auto check for miss-spelled words by having a red squiggle line under those suspect words and a spell check feature too. It is helpful for the readers to understand you more clearly.


. . . sorry about the grammar thing, all these gentlemen have been very nice but you have been very lucky no one has flamed you yet on this.

Jim

Jim, I know your read many of the threads/posts on this forum (as do I), and honestly, Ashen's posts are clearer than probably more than 50-75% of what I typically see here. Regardless, I got a chuckle out of this because I am often jokingly referred to as the "grammar Nazi" in the 930 forum for playfully poking people with a stick for their butchering of the written word (particularly concerning guys that are throwing criticisms and insults while using 3rd grade English).

[DRACO A5OG]

LOL, in law school, Professor instructed us to use 3rd grade composition in writing briefs. Dang it, I just realized, I guess I inadvertently flamed OP, my bad. Sorry ASChen. :-(

I often have to assist my Moms, can you imagine French and Korean mixed with English???

Oh great just hi-jacked OP.

Okay, back on topic. I really think it is the rear wheel bearings.

[aschen]

LOl it is fine guys. Honestly, i get alot of grief on the internet for my creative spelling techniques. You are free to harras me all you like and I won't get upset. However, I dont plan on rectifiying it either. I figure an enthusiest web forum is about the least formal written comunication venue, so I don't go to much trouble other than trying to convey my message.

Thanks ronnie, but I suspect if you crunch the numbers from pasr threads I'll have a hard time reaching that 50 percentile mark. I am pretty careless often.

Anyways it is clear I need to dig a bit deeper. I have my front hub off and the beirings out. Ill put everything back together when my pelican box arrives. It is a shame I tore everything apart for no reason.

I was nearly certain the noise was from the front, but now im not so sure. I am hoping it is not the rear bearings. I am told by pelican and the internet that these are terrible for the 930 specific rear design.

[Ronnie's.930]

Originally Posted by aschen

I was nearly certain the noise was from the front, but now im not so sure. I am hoping it is not the rear bearings. I am told by pelican and the internet that these are terrible for the 930 specific rear design.

It's not too terrible of a job if you take the trailing arms off and deliver them to a shop that will do the bearing work for you.

[rusnak]

I would have suspected the brakes if the wheels turned smothly with no play.