Das Race: My '97 M3/4/5

[Beej]

That rear shock tower is kinda strange. Is the sheet metal of the car itself bent? Do you have bumpstops? At resting height, how much shock travel is there?

Do e36's have a "lip" around the big center hole the shock mount goes through? Kinda looks like the plate is bouncing around and bending itself on something like that. That'd be loud as hell, though.

[Jake]

That rear shock tower is kinda strange. Is the sheet metal of the car itself bent? Do you have bumpstops? At resting height, how much shock travel is there?

Do e36's have a "lip" around the big center hole the shock mount goes through? Kinda looks like the plate is bouncing around and bending itself on something like that. That'd be loud as hell, though.

So that shock tower had some rust and was re-welded before I got the car. I don't know how flat the metal is underneath that backing plate, though - I think there is some sort of sealant or whatnot that is bumpy. Maybe I can scrape some of it off? I think I should remove the shock and just take a look at that corner.

The noise is pretty loud. If you take my same observations of when it gets noisy (on right turns) - we could now theorize that a right turn unloads the right rear corner and because of less weight on that corner, the shock wobbles around a bit... whereas a left turn loads up the right rear and the weight keeps everything more planted.

Does that make any sense?

[SlimKlim]

put a jack under the right rear tire (in gear, with the brake set) and compress that side to see if there's any play?

I'm going to be the outlier and guess that the upper shock mount isn't causing the problem. IIRC there is a lip that the top hat fits around, and you have two bolts that are holding the thing down from underneath, if those are properly torqued down I don't know how it would have room to move. I also think if it had play it would be making itself constantly known over every little bump, not just specifically when turning.

[D_Eclipse9916]

put a jack under the right rear tire (in gear, with the brake set) and compress that side to see if there's any play?

I'm going to be the outlier and guess that the upper shock mount isn't causing the problem. IIRC there is a lip that the top hat fits around, and you have two bolts that are holding the thing down from underneath, if those are properly torqued down I don't know how it would have room to move. I also think if it had play it would be making itself constantly known over every little bump, not just specifically when turning.

+1. I doubt it is the shock tower, but diagnosing things on sounds is hard. Maybe go for a spin saturday and see if can norrow down the noises? Maybe Joey can help you if it is a brake line rubbing on an axle :lol:

[Jake]

put a jack under the right rear tire (in gear, with the brake set) and compress that side to see if there's any play?

I'm going to be the outlier and guess that the upper shock mount isn't causing the problem. IIRC there is a lip that the top hat fits around, and you have two bolts that are holding the thing down from underneath, if those are properly torqued down I don't know how it would have room to move. I also think if it had play it would be making itself constantly known over every little bump, not just specifically when turning.

+1. I doubt it is the shock tower, but diagnosing things on sounds is hard. Maybe go for a spin saturday and see if can norrow down the noises? Maybe Joey can help you if it is a brake line rubbing on an axle :lol:

Yeah, we can try to narrow it down. The car drives fine, so I'm not too worried, but I can't think it's "normal" either.

[SlimKlim]

put a jack under the right rear tire (in gear, with the brake set) and compress that side to see if there's any play?

I'm going to be the outlier and guess that the upper shock mount isn't causing the problem. IIRC there is a lip that the top hat fits around, and you have two bolts that are holding the thing down from underneath, if those are properly torqued down I don't know how it would have room to move. I also think if it had play it would be making itself constantly known over every little bump, not just specifically when turning.

+1. I doubt it is the shock tower, but diagnosing things on sounds is hard. Maybe go for a spin saturday and see if can norrow down the noises? Maybe Joey can help you if it is a brake line rubbing on an axle :lol:

Hey man. It was the brake line bracket tapping on the trailing arm.

(The brake line rubbing the axle was on the passenger's side...)

[Jake]

OK, I jacked the car up last night to shake things around.

Both rear wheels have zero play when pushed/hit from any angle.

Both front wheels can move if shaken at 3 and 9, but you can watch the steering wheel move with them - the column is locked but has a touch of play.

The right rear shock (where the mounting plate is bent) will make some noise if you grab it under the car and give it a wiggle.

So, I think I'm going to call Ground Control and have them send me a new plate, file down any of the sealant from the shock tower repair that may be causing it to sit un-evenly, and see if that helps. This shock tower was repaired before I got the car.

If that doesn't do it, I may swap the front left hub assembly (i.e. front wheel bearing) - the front hubs came from Jim's wrecked racecar, he thinks he hit front-left first, and I remember an autocross inspector over the summer mentioning that he thought my front left wheel bearing felt like it was starting to go. I have my original hubs that were fine, so I'd just have to swap the wheel studs over when replacing. But - the noise sounds very much like it's coming from the rear, so I hesitate to think it's a front WB...

[Jake]

Swapped the shock reinforcement plate last night... what I thought was "sealant" was actually The Intern at The Bullshit Shop practicing his welding work on my shock tower. Ffffffuuu.

So, I put the (massive) reinforcement plate from TBS (they had used on the driver's side, to mask the swiss-cheese on that side) on the passenger rear tower. If nothing else, it's much thicker than the Ground Control plate and won't bend. DJ said he'd help me grind down and re-weld the tower when we have a free day.

I did go out and drive in circles in a school parking lot until I got dizzy. The wubwub noise is still there, it happens on left turns but not right turns, and it's very much coming from the rear. In doing a lot of reading, people claim they'd rather swap a motor than do a rear wheel bearing on the E36. So... clearly this won't be fixed in time for Summit Point on Friday night, and my motivation to struggle with this in a cold garage is lacking. I think it's gonna go to RRT over the winter when I have some free cash (hah, what's that?) and I'll let them handle it.

In the meantime, I can bring the 128i out to Summit and play around a little bit... it's also a TTD car so I'll get my points to close out the season.

Bah, cars suck.

[ScottyB]

ugh, sorry....wish i was closer and you'd be welcome to try all my tools from replacing the bearing in the subaru.

what is it about the rear bearing on an E36 that sucks so bad? they're just pressed in, right?

[Jake]

ugh, sorry....wish i was closer and you'd be welcome to try all my tools from replacing the bearing in the subaru.

what is it about the rear bearing on an E36 that sucks so bad? they're just pressed in, right?

Yeah, it's pressed in to the trailing arm assembly. Apparently it's just a giant pain to pull after so many years of it sitting. Given that we do have a press in the basement, I may attempt this over the winter, since I can go slow and be methodical in getting things removed. But no way am I paying RRT to do the work before Friday, it's expensive and I'm recovering from having them do the balljoints :vomit:

[navin]

<!-- m --><a class="postlink" href="http://www.youtube.com/watch?v=D4PK1jXhppE">http://www.youtube.com/watch?v=D4PK1jXhppE</a><!-- m -->

always a good excuse to buy HF tools!

[D_Eclipse9916]

http://www.youtube.com/watch?v=D4PK1jXhppE

always a good excuse to buy HF tools!

Seriously, that may be the way to go Jake.

[Jake]

The bearing is $50 and the YouTube guy says he spent $150 on tools... I'd save $300 doing that vs. going to RRT for it. Worth it.

Still not gonna happen before this weekend, but I could spend a Saturday with those tools and some beer before next season starts.

[Sully]

I haven't really been following all the posts but could diff mounts be a possibility?

[Beej]

Yeah I wasn't too optimistic that the rear shock mount would be the noise, but it's nice to have an explanation for the shape of it.

The bearing is $50 and the YouTube guy says he spent $150 on tools... I'd save $300 doing that vs. going to RRT for it. Worth it.

Man after years of being scared off of rear wheel bearing replacement (e30's, e36's, e46's)...I can't help but be cynical that it could be as simple with those tools as the above videos show. Sounds like he's replacing a bearing he already replaced recently...but still, those tools look beefy enough to handle corrosion and whatever that happens back there.

[xvxax]

http://www.youtube.com/watch?v=D4PK1jXhppE

always a good excuse to buy HF tools!

Seriously, that may be the way to go Jake.

Yeah, I bought that tool and returned it because the inner race of the bearing welded itself to the hub after 100,000 miles and was not going to let go. The easiest way to go is to just remove the trailing arms and press everything out using a press with many tons of pressure.

[navin]

Can't just cut into the inner-race and then use a chisel + screwdriver to break it off the hub? That's how I had to do it for the Honduh anyways.

[Jake]

Finally pulled my power steering reservoir and replaced the lines. They were leaking in a mostly-catastrophic manner. Fluid was ancient and almost black. DJ gave me the part numbers for hoses from Pegasus Racing so I saved a few bucks compared to the BMW hoses, and they're baller blue:



Pretty easy, just drain the fluid, undo a few bolts of varying sizes (8, 10, 13 and 22mm) and everything comes apart. I was going slow and it took an hour or so. Cut that in half for the next car I help with.

Things to be done before February (because the NASA "Chillycross" is mid-month then) seem to be:
* Add and bleed power steering fluid
* Bleed brake fluid
* Replace clutch arm bushings
* Reinstall driver's seat
* Add seatbelts and receptacles
* Replace oil pan gasket and install safety-wired oil pump nut
* Replace right rear wheel bearing (likely sending this to RRT)

[Sully]

Do you want some extra coils? One may or may not be bad. Replacing them didn't fix my idle issue so I would think they are fine. And some random heater hoses?

[Jake]

Do you want some extra coils? One may or may not be bad. Replacing them didn't fix my idle issue so I would think they are fine. And some random heater hoses?

I mean, are these coils a gift? Or do you want dollars for them?

Don't need heater hoses, I've replaced most of them by now.