Play in the brake caliper

[Jonnym]

Hello all

I have a 190D 2.5 1996 Merc with about 128000 miles on the clock.

I replaced the front brakes and discs about 6 months ago. The front drivers side has developed a rhythmic squeak when driving, it goes away when turning or braking.

When having a tyre fitted I notice that the brake caliper had some play in it. The play seems be from the way they calliper attaches via the long pins which I assume are for self adjustment.

I also notice that the wheel seemed to have a little play in it when griping it at 5 and 11 o’clock. Which I’m guessing could be a bearing on its way. But the subsequent MOT didn’t highlight that.

My question is should the calliper have any play (I’m guessing not), and what should I do to cure it, and how long would it take to change a wheel bearing?

I have rebuilt old triumphs many times but this Merc is modern technology to me!

Jon

 

[television]

I think that it is a matter of tightening the wheel bearing. I cannot see how the caliper could move unless it is lose on its mountings

 

[kth286]

Your Merc is probably an 86 not 96.

The caliper slides (slightly) on those pins and they need to be greased.

The front wheel bearings are adjustable and that should be done with reference to the Haynes manual or Mercedes manual on CD.

 

[Jonnym]

Thanks for you replies

Your right! 89-90 sorry I must have had brain fade. I did add grease to the pins when I replaced them. So there should be no play at all in the calipers, further investigation needed then

I don't have a manual to hand right now for reference to check how to tighten the bearings, but I’m guessing that will be very similar process to what I’m used to. Tighten the hex nut up by hand then back one flat etc. But is there anything I need to know about getting to the nut?

thanks for your help
Jon

 

[dieselman]

But what was there looks to be a strange nut with an added allen key locking device? I assume loosen the allen key bolt and that will allow the nut to be tightened?

Yes........

 

[Jonnym]

I investigated further in to the problem. The calliper only has slight lateral movement and no rotational movement at all. So that all seems to be OK.

The wheel bearing is another kettle of fish. I only got to it as the light was fading. After removing the cap and removing some of the grease I couldn’t see a nut. But what was there looks to be a strange nut with an added allen key locking device? I assume loosen the allen key bolt and that will allow the nut to be tightened?

Any help gratefully received

Jon

 

[Bolide]

That's a castellated retaining cover over the nut. The split pin goes through it. Remove & discard the pin, remove the cap, tighten the bearing, replace the cap & use a new split pin

The reason for the cap is, I assume, that the castellations stop the nut from turning and the cutouts allow a split pin to be inserted at multiple points round it

Nick Froome
www.w124.co.uk

 

[John Kerr]

Your Merc is probably an 86 not 96.

The caliper slides (slightly) on those pins and they need to be greased.

The front wheel bearings are adjustable and that should be done with reference to the Haynes manual or Mercedes manual on CD.

Just a thought about grease on brake calipers.Dust comes off brake pads and mixes with grease pretty soon the caliper will stick on the pins,better to replace pins with new ones or sand the old ones.

 

[Jonnym]

Just thought I would update everyone.
There was no castellated nut, but a very clever locking nut which uses an allen key headed bolt to lock it in place. Excellent design as it can be locked any where, not just where the hole in the nut allows.

There are dust caps which stop the brake dust getting in to the greased pins, but just in case I did lightly clean them with 0000 wire wool and re-grease them.

Thanks again for all your help

Jon

 

[television]

Nice of you to post back, thanks