[Mk2] [Generic] brakes

[teccyjim]

Few questions about brakes:

My discs have 2 threaded holes in them, opposite one another, what are they for?

The 'stud' holes in the discs are much wider than the diameter of the wheel studs, is this normal, if so why?

If someone cant find a solution to the bad vibrations under braking, would they like to destroy my car???

Regards,
Jimbo

[cantfindausername]

the 2 holes are for the locating screws. Completely unecessary. Holes are bigger, god only knows why, but think you could be the only person who's got an issue with it

Have you changed any components to remove the judder?

[teccyjim]

ah fair enough. yeah ive had the brakes apart, re-greased with copper grease as you should which has improved the 'feel' of the brakes however, what I have noticed is that im getting severe vibration at speed- 70+ and its undrivable. Had wheel alignment/balance- all ok. been under car and inspected all suspension/antiroll bar parts- all appear ok.

However, nearside shock absorber is leaking pretty bad. When pressing on each of the front wings to 'exercise' the front shocks, the offside moves with resistance and immediatley returns to its normal position, the nearside however 'bounces' once or twice before settling to normal.

Im a total virgin when it comes to brakes/suspension.

[cantfindausername]

Its not my prefered area either, but I would think that you should replace that shock, or the full set before looking further.

Is it judder through the pedal, steering, whole car?

[JohnnyC]

the 2 holes are for the locating screws. Completely unecessary.

They're a godsend if in a few years time you need to get the discs off and they're 'attached' themselves to the hub, just screw a bolt in and it'll free the disc

[teccyjim]

the judder is through the whole car, noticeable at all speeds, bad at 60mph, undrivable if any faster. Hit the brakes, it just gets worse.

thanks guys,
jimbo

[cantfindausername]

the 2 holes are for the locating screws. Completely unecessary.

They're a godsend if in a few years time you need to get the discs off and they're 'attached' themselves to the hub, just screw a bolt in and it'll free the disc

Good point. I never though about that when I was removing a pair of discs. I think beating the sh!t out of them was more satisfying at the time though.

[RichardK]

Have you checked the suspension top mounts?

I had a Scorpio which went through "discs" like one-one's business. Replaced EVERYTHING, spent loads.

Sold it.

Turned out it was the top mounts... which I tend to forget play such an active part in the car's suspension, having grown up with 1970s Vauxhalls and BL stuff.

[cantfindausername]

the judder is through the whole car, noticeable at all speeds, bad at 60mph, undrivable if any faster. Hit the brakes, it just gets worse.

thanks guys,
jimbo

If its the whole car I would look at suspension. Generally I'd say brakes will judder up through the pedal and steering only.

[teccyjim]

not sure what to look for exactly with regards to the top mounts- i checked the four bolts at the top of each, nipped them up a little but has made no difference. Do i need to remove the whole shock absorber to fully inspect the top mounts and what should i be looking for damage/wear wise???

jimbo

[RichardK]

The four bolts only hold the mounting, there's a sort of bearing/bushing arrangement attached to that. I don't know how to check an MR2 specifically, on my Volvo they clearly detached, on the Scorpio it was hard to tell.

[SimonPearse]

are you on standard wheels? If not have you got the correct hub rings fitted? if not that's your problem.

[cantfindausername]

Simon is that what sometimes called the spigot ring that you're referring to?

[teccyjim]

ive currently got standard wheels on. ive got some free time early next week, i'll take em off and have a good look.

many thanks guys
jimbo

[SimonPearse]

Simon is that what sometimes called the spigot ring that you're referring to?

yup

[brgbrm]

Did you get anywhere with this Jim?

[djpkins]

I had an almost identical problem to this when I first got my 2...it went away completely when I changed the suspension to coilovers. The front, left Shock was fubarrd and so was the top mount...If your discs have warped slightly this will obv also cause a bit of a wobble when braking but you feel only really feel it through the steering wheel...If your prob is going through the whole car...have you had a passenger in it for a second opinion?

[DeusMR2]

ah fair enough. yeah ive had the brakes apart, re-greased with copper grease as you should which has improved the 'feel' of the brakes however, what I have noticed is that im getting severe vibration at speed- 70+ and its undrivable. Had wheel alignment/balance- all ok. been under car and inspected all suspension/antiroll bar parts- all appear ok.

However, nearside shock absorber is leaking pretty bad. When pressing on each of the front wings to 'exercise' the front shocks, the offside moves with resistance and immediatley returns to its normal position, the nearside however 'bounces' once or twice before settling to normal.

Im a total virgin when it comes to brakes/suspension.

erm unless I've missed something then that is the reason your car is bouncing and it will get worse with braking (especially if its a front wheel). The spring is undamped and is naturally just bouncing all over the place. Change the shock and all the bad bouncing will go away