Tracing a knock from the front

[hvanman]

I recently changed the whole front suspension and now have a fairly loud knocking when I go over bumps. I've had the car on a jack (under the sub frame mounting to the floor) and can't find any obvious play in the anti-roll bar bushes or anywhere else. I did find that if I set the suspension to low and then pushed the wheel up, there was slack and movement in the strut when pushed upwards, but once under normal pressure this is not there, so maybe this is normal?

I am a but stumped and have tried checking with the suspension on high and low, but no luck, is there a specific way to check for play that would help show up play with the joints under or not under a load?

Thanks, Simon.

[JayW]

Best thing to do is jack up the whole front so the wheels are hanging equally otherwise the antiroll bar will be transferring the weight from the other side. Then with the suspension on normal height you can rock the wheels on the steering lock to check the TRE's and get a bar in the ball joints and droplinks and wishbones.

[Tim Leech]

. I did find that if I set the suspension to low and then pushed the wheel up, there was slack and movement in the strut when pushed upwards, but once under normal pressure this is not there, so maybe this is normal?

Thanks, Simon.

Yes Simon thats normal, found that out myself when trying to locate a "knock" myself from the nsf. Turned out that when I had some pads fitted at work, the goons couldnt be bothered to refit the cooling duct to the caliper. So even though the bolts were tight the space left behind by the missing as it acted as a spacer allowed the caliper to move causing a knock.

[hvanman]

Great, thanks for the advice, I hoped the movement in the struts was normal (and I know I refitted the cooling ducts and the calipers are brand new, so no movement from them now...), so I will get both wheels up with axle stands on the sub frame mountings and see if I can get some movement with the pry bar.....

[mat_fenwick]

when I had some pads fitted at work, the goons couldnt be bothered to refit the cooling duct to the caliper.

I'm puzzled why they even removed it to change the pads!

[mds141]

when I had some pads fitted at work, the goons couldnt be bothered to refit the cooling duct to the caliper.

I'm puzzled why they even removed it to change the pads!

Spike Milligan, Michael Bentine, Harry Secombe AND Peter Sellers all working as mechanics now, must be hard up. Hang on aren't they all dead!

[Tim Leech]

when I had some pads fitted at work, the goons couldnt be bothered to refit the cooling duct to the caliper.

I'm puzzled why they even removed it to change the pads!

No idea, he removed the caliper for some reason?

[Kitch]

when I had some pads fitted at work, the goons couldnt be bothered to refit the cooling duct to the caliper.

I'm puzzled why they even removed it to change the pads!

No idea, he removed the caliper for some reason?

Cooling duct?! On the front brakes?

[mat_fenwick]

I reckon it's a dirt shield, unless mine is missing a vital bit of equipment?

[JayW]

It is supposed to be for cooling. I usually leave them off and have never had any problems with it, certainly not knocking from the calipers.

[Dollywobbler]

That's an interesting one as I left the broken remnants of plastic and their holder off on mine, which now clonks. Only on one side though, and I did this on both, so far from conclusive. I'll report back on mine once I've had an investigation tomorrow.

With the balljoints, a bar underneath the wheel to simulate load may help find play. The weight of the hanging wheel can remove it otherwise.

[Tim Leech]

Theyre made of metal on the gt, and look to duct air into the brakes so would be no use a dirt shield. Whether they work or not it knocked its tits off when removed....

[Dollywobbler]

All I've got left is a metal bracket with a tiny amount of broken plastic on it, which I presumed was part of a scoop or shield. I'm certainly going to check the fit tomorrow now. Could be a very easy fix for the problem.

[mat_fenwick]

I really can't see how it would cause a clonk though, unless the metal bracket is missing and the bolts bottom out of thread before the caliper is tight as what must have happened on Tim's car. It's fairly shocking that a garage would let a vehicle out with a loose caliper though!

[docchevron]

the bolts should still pull down tight with or without the brace..