Knocking

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Sun Jul 16, 2006 4:39 pm

i installed my new alloy arms today with eccentric bushes, went pretty well considering i was melting

however, once the arms had been fitted and i went for a drive, there was a knocking from the left side. its only when the car is being driven, not when the car is stationary. It also only happens once the wheel as done abou a half rotation, then it does not occur for the rest of the turn.

the ball joints were cheked before fitting by a competant garage so i know they are fine, they also fitted the bushes. All the bolts are tight, iv triple checked them all and also nothign is knockign or clearing, iv double checked that when the wheel is turned also.

help!
User avatar
georob
E30 Zone Camper
E30 Zone Camper
Posts: 1106
Joined: Thu Feb 03, 2005 11:00 pm
Location: Aberdeenshire

Sun Jul 16, 2006 5:35 pm

I get the same when going round left hand bends, still cant suss it out. :mad:

If you do, let me know what it was

Thanx
Jon_Bmw
Dangerous when thinking
Dangerous when thinking
Posts: 7606
Joined: Tue Jan 11, 2005 11:00 pm
Location: Salisbury

Sun Jul 16, 2006 5:44 pm

Hmm it does sound like ball joints to me. Do they do it when turning a corner more or the same amount as if you were on a straight. Is it vertical motion that sets them off, i.e over little bumps and lumps in the road.

Dan i remember you posting a topic on ball joint rubbers or the like, did you replace the rubbers before the garage inspected them or something? Did the ball joints move freely when you had them off the car.

Last thing, did you change anything else whilst doing the arms, or did you remove/move/knock anything.

Simple questions...but hopefully they'll lead to simple answers :thumb:
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Sun Jul 16, 2006 5:48 pm

dude, the ball joints themselves were checked with the rubbers removed by the garage and all deemed to be spot on. im now using the rubbers from my old arms, of which only one was slightly split which was a result

ball joints moved freely yes! i changed the links obviously i think this might be the cause but it is definatly bolted down correctly and in the right position so im a bit confused! especially as its only on the left side
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Sun Jul 16, 2006 9:21 pm

anyone?
User avatar
6inline
E30 Zone Newbie
E30 Zone Newbie
Posts: 66
Joined: Thu Sep 29, 2005 11:00 pm
Location: Europe

Mon Jul 17, 2006 7:33 am

I've experienced that recently...and it turned out to be the disc protectors(pushed when changing the steering) touching at a particular moment the steering ball-joints...Hope this is the reason, as I've spend two weeks snooping around the car to find it out
Bob_S
Engaged to the E30 Zone
Engaged to the E30 Zone
Posts: 5412
Joined: Sat Jun 11, 2005 11:00 pm
Location: chester, cheshire

Mon Jul 17, 2006 7:47 am

check your top mounts, my mate changed his lower wishbones and his top mounts started to knock like a bugger then again he did ruck it and cause a bit of damage check them either way
Bollocks to this 24v scrap!
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 10:14 am

6inline wrote:I've experienced that recently...and it turned out to be the disc protectors(pushed when changing the steering) touching at a particular moment the steering ball-joints...Hope this is the reason, as I've spend two weeks snooping around the car to find it out
Good call! they did look a bit shagged!
Bob_S wrote:check your top mounts, my mate changed his lower wishbones and his top mounts started to knock like a bugger then again he did ruck it and cause a bit of damage check them either way
Whats the procedure for checking top mounts bob?
Bob_S
Engaged to the E30 Zone
Engaged to the E30 Zone
Posts: 5412
Joined: Sat Jun 11, 2005 11:00 pm
Location: chester, cheshire

Mon Jul 17, 2006 10:54 am

er, dunno ask someone else lol just drive about and see if you can tell where the knocking is coming from
Bollocks to this 24v scrap!
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 11:40 am

i checkd the backplate im im 90% its not that. the thing is it only happens when your driving so its a real pita. its definatly coming from the front left and a few passengers have said it feels like its coming from underneath the car. i did a free play test thing on the wheel from side to side an there was a small bit of play.

its ball joint isnt it :cry:
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 2:45 pm

tightened up the ARB link earlier, even though it wasnt that loose, and it threaded and is just spinning. its the 13mm bolt/nut that goes through the bottom of the link/wishbone. the knocking stopped for a while. then on the return journey home, it began knocking again on the left side only, but it now knocks on left turns, right turns, and bumps?

??
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 5:15 pm

BTTT someone must know!
Demlotcrew
E30 Zone Team Member
E30 Zone Team Member
Posts: 13329
Joined: Mon Dec 20, 2004 11:00 pm
Location: East Anglia

Mon Jul 17, 2006 5:19 pm

Buy a new bolt that you rounded off and see if that fixes it.

Andrew
Jhonno
Homo Hair
Posts: 20362
Joined: Mon Jan 10, 2005 11:00 pm
Location: FLAT, FLAT, FLAT!!
Contact:

Mon Jul 17, 2006 5:20 pm

ball joints should be nice and tight.. when they get loose they are worn

can you feel it through the steering wheel?
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

Image
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 5:28 pm

cant feel it through the wheel. can only here it, passengers can allegedly feel it when it knocks hence why i hope its something clashing.

what are the symptoms of warn ball joints?

the garage checked them and said they were fine, no vertical movement, and they seemed stiff but moved without any hastle or excess force when they were off the car

il try that bolt but i cant see it being that to be honest!
User avatar
georob
E30 Zone Camper
E30 Zone Camper
Posts: 1106
Joined: Thu Feb 03, 2005 11:00 pm
Location: Aberdeenshire

Mon Jul 17, 2006 5:55 pm

I totally have the same prob as you

So far there has been new control arms, tie rods, tie rod ends, tie rod cv's, balljoints, offset control arm bushes. arb links, arb brackets/bolts and struts

Still the bloody knocking :x :mad:

Theres bugger all left for me to replace, the rack is aok as had that checked. And new wheels fitted/ balanced, tracking 100%.

Now i'm poss thinking the top mounts gone perhaps? What are the symptons for these failing???
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 6:03 pm

i thought top mounts, but why would the top mount start knocking as soon as i fitted a lighter wishbone? does yours knock on straights as well as corners?
Simon13
The longest resto in the world !
Posts: 22697
Joined: Mon Jan 10, 2005 11:00 pm
Location: Camberley, Surrey don't u know

Mon Jul 17, 2006 6:04 pm

could be your shagged control arm bushes

probably a ball joint though. How competant are they? how can u check a worn ball joint off a car?

Jack it up on that side and move the wheel, jiggle it if there is some play there it's most likely the ball joints bert
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 6:09 pm

allready done the good old wiggle the wheel test. there is a tiny bit of play but nothing out of the ordinary to me. i compared both sides and the quite side has hardly any more noticable play than the other.

the bushes may not be bmw but they owuld not cause knocking, bert :evil:
User avatar
georob
E30 Zone Camper
E30 Zone Camper
Posts: 1106
Joined: Thu Feb 03, 2005 11:00 pm
Location: Aberdeenshire

Mon Jul 17, 2006 6:09 pm

nah, just on corners it knocks

not my balljoints as brand new feckers fitted
Dan318-is
Married to the E30 Zone
Married to the E30 Zone
Posts: 8006
Joined: Wed Jul 06, 2005 11:00 pm
Location: Surrey/London

Mon Jul 17, 2006 6:10 pm

is it only noe side of yours which is knocking rob? mines on straights too so im beginning to think it is the ball joints

what will the effecst be if they aint replaced etc?

might get the garage to look tomorrow :?
Post Reply