John G

Hi Everyone...... After years of wanting one I finally picked up my Scooby tonight............BUT..... I'm driving down a fast straight road, see traffic ahead..... start braking NOTHING....... Bit of a panic then try again and brakes are fine. It did this about 5/6 times on the way home....... Help, What can it be????? The pedal feels like when you brake hard with ABS and as soon as you release it and try again they seem fine.!!!! I ain't got a clue but I hope someone on here may know..... I spent years trying to persuade the missus to let me get one now she's petrified of it. The car is a 1995 Subaru Impreza Wagon 2.0 Turbo. All brakes are standard Cheers JohnG

Fuzz

sounds like a travel issue more than a fluid issue to me.
The pads could be getting knocked back from a wheel bearing issue or maybe you have a "sticky" caliper...
either way get them checked out ASAP before it keeps going to the floor

Andy

Postman Pat

If you check all above and no wiser it might be your master cylinder. Our 405 was doing the same until I changed that.
Pat

Dyney

John
Welcome
Sorry this had to be your first post

If there are no leaks from the calipers hoses or master cylinder (I doubt there will be). Jack up the front wheels and check for play in the wheels bearings.
If the bearings have gone the wheel will wobble.
On the road the bearing allows the wheel and disc to move (especially on cornering) and this pushes the pads back so when you first press the pedal all the fluid does is push the pads to meet the disc but not enough to actually slow the car. The second push actually pushes the pad against the disc.

John G

Cheers for ya help guys.!!!! I've just found out that both my rear calipers are siezed solid so that could be part of the problem.!!!! Gonna have to sort that and get everything checked while it's in. Thanks again JohnG

Fuzz

Andy

crusher

bad luck mate

John G

Is fixing the siezed calipers gonna be a remortgage the house job??? Other than not being able to stop the car is awesome, I've had an RX7 and a Porsche 996 but this one is nicer to drive than both of them>!!!!!!

babber

I think I've been getting this on my RB5 lately and thought the brakes needed bleeding and fresh fluid put in. Seems like my wheel bearings are fine (or so I'm told) so reckon it has got to be the fluid. I'll try and change it this weekend and feed back if replacing the fluid helps.

I've also been reading on here about the bulkhead flexing and wondered if it could be that?

Thanks Phill

SCOOBY TOWERS

iTrader: (7)

Babber,
Bulkhead flex is only at the limits of braking and is very difficult to feel under normal braking. AT full pressure the master cylinder tries to dip and therefore bends the bulkhead. A braket from the suspension turret tries to stop this happening.

More than likely your hoses are shot at, especially if you can depress the pedal 1/2" more by pressing harder.
RB5 will be a 99 so the rubber in you hoses will be past its best.
Uprate to goodridge and you'll feel the difference instantly.
Top it off with a fluid chage to be on the safe side.

DocJock

Pad knock off is also a symptom of worn hub carriers, which is more common than a failed bearing.

John G

Had my calipers done.... New pads on rear and it's still doing it.!!!!! The brakes 9 times out of 10 work fine but occasionally when you press the pedal it feels like the pads aren't moving and the car weaves about,The pedal goes solid and as soon as you let go and press em again they work fine.!!!! Nobody seems to know wot's causing this, It won't do it when the garage test drive it and my laundry bill is going through the roof.!!!!! Help, Any ideas?????????????????
: P.S The discs and pads up front are almost new as well.!!

awd wrx

if all is new or working , as in discs and calipers , I would think its the master cylinder , when these go they usually just go without any reason

babber

I reckon mine are doing the same as yours. Had new disks all around new pads. A mate of mine is replacing the fluid this afternoon with new DOT 5. I've already got braided hoses and they've been on there for 4 years. Do they decay?

I'll report back later if it makes any difference

As mentioned before, it's really annoying and my misses is complaining about it now

Thanks Phill

John G

My mechanic reckons that it's probably a seal gone in the servo or master cylinder..... It's going in on Tuesday and I'll let ya know what happens.!!!

babber

Just got back from having the fluid replaced, so will see how it goes.

When you say a seal gone, will fluid be leaking or will air be getting drawn in?

Thanks Phill

John G

Theres no fluid leaks anywhere so I presume it must be air getting in somewhwere. It's in now having surgery performed so we'll have to sit and wait.!!!!! Hopefully it's repairable and won't need a Master Cylinder or something expensive.!!!!!

Fuzz

I hope that was a misprint babber and you meant 5.1 fluid.

DOT 5 is silicone based and not compatible with any other type of fluid.
Also you'll end up with an even softer pedal than before.


Andy

John G

Finally found out...... It's the Servo (well done everybody who already knew that ) New question...... I've been offered one off a 97 UK WRX but will it fit on my 95 UK Turbo???? I don't know what, if any the difference is between the 2 cars and if I'm being stupid I apologise in advance Cheers JohnG

stockcar

exactly the same..................

Cisco Kid

I'm having same problem with my MY99. I had a go at changing the servo but struggled to get the old one off as the turbo heatshield was in the way. Couldn't get all the bolts off the heatshield and ended up giving up. Any tips or am I doing something wrong ?
Thanks

SCOOBY TOWERS

iTrader: (7)

Top tip - Small hands !

Seriously though -
Take your time with the heat sheild bolts - ratchet spanners help a little, but there just awkward to get to.
A bit of paitence will have em out

Cisco Kid

Thanks, are you supposed to be able to get them all off from the top ? I couldn't see any way of getting to the lower one(s) from the top but then I couldn't see how to get to them from underneath either. Thanks for any comments

Fuzz

easy.

with a long 10mm socket on a 1/4 drive ratchet undo 2 down on the left hand side, put your hand down between innner wing and wiring loom.
If tight put a 3/8 drive extension bar on the handle of the 1/4 drive ratchet with the other hand.
Back bolts near the top and the very top ones can be done with a spanner, ratcheting one is quicker.
There are then two to undo near the steering knuckle, the top one is done from the top, again with a spanner (backwards) and the bottom one from below, also with a spanner.
on the right of the exhaust there is one facing up towards you, use a wobbly drive 10mm socket on a long extension to get that one.
Grab heat shield pull up, twist to the right and pull out to the right.


Well that's how I do it anyway.

Andy

John G

Changed the servo and it's done f#@k all........ Absolutley no difference at all.!!!!!!! I'm gonna put new discs and pads on the rear then if that don't cure it then I'll stick it in a ditch and claim the insurance I'm totally lost, My garage can't find any leaks etc and it never does it when I take her in.!!!!!!! My rear discs are a bit grooved so it could be those but would that really make that much difference???? HELP PLEASE

struv

you sure your pressing the brake pedal and not the clutch? sorry it might be master cylinder seals i think the fluid is creaping past the first seal in the master cylinder

Cisco Kid

Thanks for the tips, I'll give it another shot as soon as I can, but I've just found that my rear calipers are virtually seized as well so I'm going to change these first. I think I have the same problem as John. If I still have a problem after the caliper change then I'll try the servo change again... I managed to buy one off Ebay

John G

Cheeky Fu#?er.!!!!!
If it was a seal gone wouldn't there be fluid leaking out??? There are no leaks anywhere. How can I test this??? Cheers John