A rant and a request to BC coilover owners

smy0003 · Postby **smy0003** » Thu Jan 22, 2015 4:45 pm

Hi guys, new problem today.
My 5 started making some strange noises the other day so I took it to Pedders for a $28 test/check thing.
Turns out my right rear wheel bearing (try saying that over the phone quickly) is stuffed, apparently because my BC coilovers have too much preload in the rear.
I honestly don't know how much preload is on them tbh, and as my set never came with the C-spanners I have no way of finding out.
Yes, I could buy a pair, but $40 isn't easy to part with as I'm about to spend some money getting MX5 Factory to put new rear wheel bearings in.

So, does anyone else in Vic have a set of BC C-spanners they could lend me for a day or two?
Pretty please?

It's my fault for not checking as soon as I got my second hand BC's, but I'm still peeved.

hks_kansei · Postby **hks_kansei** » Thu Jan 22, 2015 5:23 pm

I would be suspicious if "preload" is the excuse.

Preload normally refers the the springs on a shock being squeezed tighter than they otherwise may be, this has no connection with a wheel bearing at all.

In fact, I would say that the shock/spring combination has very little to do with the wheel bearing (unless the car is stupidly low, or has stupid camber)

The big things I would expect to cause a stuffed bearing are:

Age (the most likely one, since NAs are 25 years old now, and NBs are hitting 15)
Wheel offset (really low offset wheels can put strange loads on bearings and cause them to wear faster)

Also, I would suggest getting quotes from other shops too, MX5 Factory often aren't the cheapest/best from my experience.
Allmaz in Clayton have always looked after me (now I just get my GF to do my work since she's a mechanic

)

lightyear · Postby **lightyear** » Thu Jan 22, 2015 5:27 pm

I have 2-3 sets of spanners. You are welcome to borrow a set. In bentleigh.

bruce · Postby **bruce** » Thu Jan 22, 2015 5:31 pm

I agree. It's just wear and tear as the cars age.
Preload is set from the factory. Too complex for a hoo-man being to figure out. I just tightened mine up trying to get rid of a knock.

Magpie · Postby **Magpie** » Thu Jan 22, 2015 5:46 pm

Sorry I have to cough "bullshit"...

Too complex for a hoo-man being to figure out, not true it is quite easy.

A quick and dirty way is the wind down the upper collar until the spring is uncaptive, wind the spring back up till it touches the spring. Wind the second collar up to touch the upper collar. Wind the top collar up and measure the gap. If you have 9kg/mm front springs 5mm gap equals 45kg preload, simple. When you have the desired preload wind the bottom collar up and lock them tight.

Now I'm not saying that 45kg is correct as I don't use this method! I use scales and set the shock length first then corner weight by preload.

Adjusting preload does not change the suspension travel if done the right way.

bruce · Postby **bruce** » Thu Jan 22, 2015 5:55 pm

...and that confirms it.

smy0003 · Postby **smy0003** » Thu Jan 22, 2015 7:12 pm

Car isn't slammed and wheels are standard so perhaps just age.
I'll double check everything in either case.

Lightyear you're a champion, I'll shoot you a PM.

Rob · Postby **Rob** » Thu Jan 22, 2015 7:19 pm

Has anyone ever come back from a free or cheap "check up" without being told something chronic/expensive/must fix ASAP is wrong?

smy0003 · Postby **smy0003** » Thu Jan 22, 2015 7:46 pm

I went in asking them to diagnose a very obvious noise. They didn't even mention fixing it themselves, no quote on the form or anything.

zossy1 · Postby **zossy1** » Fri Jan 23, 2015 8:02 am

Magpie wrote:Sorry I have to cough "bullshit"...

+1. It wasn't the coilovers.

Regie · Postby **Regie** » Fri Jan 23, 2015 8:04 am

first mistake is you went to Pedders..

No way the coil overs could contribute to your wheel bearings (if they are stuffed at all) in the configuration you are running.

Is it a knocking noise?? Could be sway bar end links

kazama · Postby **kazama** » Fri Jan 23, 2015 8:08 am

Regie wrote:first mistake is you went to Pedders..

this

smy0003 · Postby **smy0003** » Fri Jan 23, 2015 9:08 am

No it's not a knock. It sounds like my handbrake was on all the time. It's a grumbling noise.
The car will be up on jackstands today to confirm play in the toe.
I'm not an idiot, no matter what the cause I'll be checking everything myself today to confirm.

Regie · Postby **Regie** » Fri Jan 23, 2015 11:39 am

could even be the rear pads are down to their minimum and are on the indicators. Does the noise go away when you put the brakes on?

hks_kansei · Postby **hks_kansei** » Fri Jan 23, 2015 11:42 am

smy0003 wrote:No it's not a knock. It sounds like my handbrake was on all the time. It's a grumbling noise.
The car will be up on jackstands today to confirm play in the toe.

Grumbling sounds like a wheel bearing. Or a diff centre.
Most likely the bearing though.

As well as seeing if there's any play left/right also spin the wheel by hand and see if it does it easily, and smoothly.