strange noise when I brake while reversing, and other stuff

Peter F · Post by **Peter F** » Sat Apr 24, 2004 7:20 pm

Hi,

I have a 91 MX5, done 205,000km, occasionally when I brake while reversing
it makes a low pitched groaning noise when i press the brake pedal, like
dragging a chair across a school hall, but then sometimes it doesn't,
obviously a brake thing, but my brakes work fine still in every other way,
passed WOFs.

Also with regard to the 15 percent discount through the club at John Andrew
Mazda, does it actually make it cheaper to service there as opposed to going
to any other garage? Dealerships aren't known for their value for money, so
does it just put them on a similar price level with other garages?
I do my own oil changes so only pay garages for tune-ups and major repairs.
A cambelt is due, and a new clutch eventually.
Done reasonably well getting to over 200,000 on the first clutch. I see some
(supposedly) low mileage MX5s for sale saying 'new clutch' and think it's
got to be wound back to have needed one so soon or had a hard life

Peter.

[...]

Michael Donovan · Post by **Michael Donovan** » Sat Apr 24, 2004 9:07 pm

Hi Peter
is the groaning fairly or very loud?

mike

Michael Donovan · Post by **Michael Donovan** » Sat Apr 24, 2004 9:11 pm

Also did you notice any not so loud squeal coming from any of the brakes
before the 'groaning' began?
Cheers
Mike

Peter F · Post by **Peter F** » Sat Apr 24, 2004 9:13 pm

It's only fairly loud

[...]

Michael Donovan · Post by **Michael Donovan** » Sat Apr 24, 2004 9:32 pm

Hi Peter
O.K.
Your problem is probably different to mine.
Some time ago I had a mildy squeaky right rear brake. I thought it might be
a stone stuck between one of the brake pads and a disk. THIS is what you
might be experiencing. I put my car in for a warrent which it passed as usual.
About 3 days after getting the warrent I was driving home and at a
supermarket my car suddenly began to make a real loud groaning noise.

The long and short of it is that both the rear brake calipers had 'frozen'.
What I mean is that they (on a 1990 model) have one piston per brake
caliper. When the brake pedel is depressed the piston pushes against one of
the brake pads and at the same time as that pad is pushing in on the disk to
brake the car, a part of the caliper assembly itself moves away from the
disk so that the brake pad on the opposite side of the disk to the piston
pulls in on the disk. When this happens there is only a very slight movement
of the caliper as a unit. There are two pins(one upper and one lower) that
allow the caliper to float backwards and forwards. The upper pins on both my
rear calipers were locked solid. The result was that every time I braked the
inner brake pad on each caliper pushed against the inside of the disk but
the outer pads are doing nothing.

So the outer rear brake pads looked like they were brand new while the inner
ones were worn right down so that there was no pad material left and the
groaning noise I was hearing was the steel of the brake pad backing gouging
into the disks and destroying them. Or at least requiring resurfacing and a
lot of work on both calipers.

Hopefully yours is just a stone stuck in there, however I get it checked
properly if I was you.
Good luck
Mike

nmr · Post by **nmr** » Sun Apr 25, 2004 9:05 am

The long and short of it is that both the rear brake calipers had 'frozen'.

I get the impression that this is a standard problems with MX5s. It might
almost be worth fixing before it happens!