Bad Vibes

blueji · #1 04-05-2005, 03:10 PM

Hi all, I'm looking for answers, pointer or any advise on the well know problem of brake judder. My SVX seems to have relatively new standard discs on the front, but the next stage in "restoration" is cleaning up and servicing the struts, calipers etc. I've seen the discs on offer on ebay (X drilled)in the US and going on past motors solved the problem complete with a set of EBC green pads. I,m trying to keep to originality as much as I can and dont want to go down this road. Anyone care to offer there valuble and much appreciated help.

John

(Air mailed your part yesterday Joe.)

Earthworm · #2 04-05-2005, 03:15 PM

When you put the wheels on did you torque them correctly? Some people have had vibrations disappear after retorquing.

blueji · #3 04-05-2005, 03:24 PM

Nope, can't say I did I just swung on the wheel wrench like usual. The vibration comes and goes from day to day.......total confused. What is the torque setting by the way?

Earthworm · #4 04-05-2005, 04:07 PM

I tighten all to 50ft.lbs in a star pattern then all to 80ft.lbs in the same order.

blueji · #5 04-05-2005, 04:24 PM

Thanks, made a note and will try,

ensteele · #6 04-05-2005, 05:02 PM

When and if you go to new rotors, I would suggest going with stainless steel brake hoses. That makes a big difference as well. Good luck.

#7 04-08-2005, 09:21 AM

I had the EBC green with my standard discs. Much better than standard, but fade like crazy after one or two hard stops. When I changed to my Skyline, I was recommended by a brake factors not to use green as they are not designed for such a heavy car (roughly the same weight as an svx). I have put EBC red ceramics on and they are excellent, with no fade at all. Bit pricey but I feel more secure than with the greens

blueji · #8 04-08-2005, 03:04 PM

What price for comfort and quality? I certainly know ebc green worked and created a lot less dust! but this is the pointers/advise I'm looking for and will most likely go with red now. thanks

#9 05-05-2005, 08:17 AM

My first SVX had horrible brake judder, and I tried everything I could to fix it. In the end, the problem was totally resolved by replacing the rear (yes, rear) brake disks.

blueji · #10 05-05-2005, 12:53 PM

Ta blackbird for the pointer, its in for a sevice next week i'll ask them to take a closer look

John

svxistentialist · #11 05-06-2005, 09:38 AM

I cured the judder in mine by having the disks skimmed on the car. Did a right good job of straightening them up too, and was not too expensive, maybe 100 Euro if memory serves.

Right now, the brakes on my Jap import Legacy Rumblewagon are spongy, not inspiring confidence.

A scooby WRX nut tells me I need to change the pads. Either from lying up, or the salt on the sea journey, or both, causes the pads to glaze, so they don't grab the disc.

So I think I will look for the EBC red ones Tony uses, the Wagon is about the same weight as the SVX. Thanks for the tip, Tony.

Joe

blueji · #12 05-06-2005, 03:19 PM

Just when I thought things were going good, was out tonight for a run and decided to let her stretch her legs on the M8 on the way home, after 4 or 5 miles at warp factor 9 there seem to be a light rummble building up almost as though it was road condition but when I braked to come of the motorway the bloody thing juddered like nothing else! I cleaned the front brakes 2 weeks ago to discover the bottom bolt/pin was dry and quite stiff, after re-assembled with plenty of copper slip it was so smooth...and then this!!!.......I'll never slag a Nissan Micra again.

Any thoughts on that one?

Time for a wee half.....

John

svxistentialist · #13 05-07-2005, 03:04 AM

John

Sorry to hear of these woes, but Rule #1

Don't panic!

The situation you describe is what most people get when they experience disk warp. It seems to only need one hard stop from plus 100mph speeds to create enough heat to show the problem.

I'm assuming here, you have not changed to new disks, yes?

If all 4 of your disks have enough meat on them, your first thing to do is have them skimmed. This will true them up.

Also, when putting on your wheels, you remember the advice about torqueing up the studs? I tighten mine inthe order 1,3,5,2,4. Doing this torqueing up while the wheels are on the ground is no good You have to do the initial 50 lbs torque up while the wheel is off the ground. Then let off the jack and tighten up to spec. For all 4.

If you want to investigate which disk or disks are warped, you can do the following, but be ultra careful doing it. Get a big garage trolley jack, and lift one side of the car completely off the ground, and take the two wheels off for access. Start the car in P. Leave off the handbrake. Make sure the two wheels on the ground are chocked, and chocked well. The two wheels, hubs, in the air will spin when you engage D. Don't rev it in case the diff locks drive it off the jack, you don't need that problem

Now, if you have a warped disk, you may be able to see the wobble. It may only be a little out of true, and there is a device for measuring Run-Out as our US friends call it. The simple way is hold a screwdriver to the surface of the rotating disk. If it's OK all will be smooth. If it is out of true, it will grab and release the blade. As little as one grab per revolution will give you judder.

Be really careful doing this, make sure your diff lock fuse in in place and working, and keep kids away. Note also, it could be a rear disk as Dave found out on his one, above.

Skimming them if they are not too worn is a good and cheap solution.

Best of luck

Joe

PS
As yours is UK, you will be aware of the pedal pumping back at you with ABS working when braking heavily in slippery conditions? It's only when you feel it in the steering wheel you have a warpage problem.

blueji · #14 05-07-2005, 05:02 PM

Joe, thanks again for responding, I will put your sugsestion on my to-do list. Would or could the fact that I have put locking nuts from my Impreza on my svx have an adverse effect on the sistusation due to them having a tapered seat rather than the flat ones on the correct nuts, is there a dedicated type of locking nut for the svx?.
Got the car booked in for a service next Sat 14th, and asked them to pay more attention to the brakes, I would normally do the work my self but it has FSSH and I would like to keep it going, I hate garages they're not as fussy as us but Nobles seem to be good.
As I said before I cleaned the front discs and calipers but not the back ones as Dave pionted out, we will see what happens after the service but need to get it sorted if I'm to pay Peterborough a visit!

Need to go, the ice in my malt is melting!!

John

svxistentialist · #15 05-07-2005, 05:40 PM

I would be a bit worried about the Impreza nuts possibly not seating correctly.

This might seem OTT and daft, but to see if it was giving you a problem, I would torque up a wheel with 5 SVX nuts, 80 lbs, then wind off one of them, and replace with the lock-nut. Mind you, John, if the taper was much different than the standard SVX nuts, I would leave it out altogether.

My ice too.

See ya.

Joe