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MG Midget and Sprite Technical - rear suspension noise
|over the weekend I have developed a creaking and slight knocking noise from the drivers side rear suspension, the creaking could be the polly bushes but at a loss about the knocking unless its the front spring bush it was replaced 11 years ago so with how rubber last today I suspect that any other ideas before I strip the spring off.|
|Give all the hardware a good nip up with a wrench rachet or spnner in the rear suspension ...most likelythat will solve it...we see this from time to time|
If thwt dosnt fix it check the shocks out make sure they have fluid
|Damper mounting bolts perhaps?|
|Damper oil escaped and gone dry?|
|disconnected drop link and it still makes the noise will up load a video to youtube later|
|video with the creaking on here|
|Its. Bad link... "incorrect video id"|
Did you get a wrench on all the bolts and hardware in the rear suspension ... you mentioned the shocks were okay
|I can't get the link to work here either but the video is called 'creaking mg midget suspension' uploaded an hour ago.|
if you hadn't already discounted the damper that would have been my guess but perhaps creak and knock might be a cracked broken spring(?).
|sorry dont know how to make link work if you copy and paste it into the address bar it seems to work, think its spring off then and I can re-grease the polly bushes at the same time unless it is the polly pads on the springs.|
|You could be right Nigel one of the spring leaves is out of line at the front but all are in line at the rear
what you could do is get an oversized stethoscope (I favour the extension tube from a vacuum cleaner) have one end held on or near where the think the spring might be faulty and then some bounce the corner again, you can move the end along or around the spring to pinpoint the noise if it's on the spring but bear in mind noise (vibrations) can be transmitted from another area/item too . You'll need a glamorous assistant or at least three hands if not four hands.
The tube could help to locate the source of the noise whilst to some extent eliminating extraneous and/or background noises that might cover or distract.
I'd do above before undoing anything plus a clean and lubricate in situ, if the spring isn't broke then a clean and lube may get rid of the creaking but not the knocking.
The two noises may not be coming from the same source or place, but are probably related noises. If you can eliminate or quieten one it will make the second easier to locate (well maybe) - or they might be be from the same source.
|I wouldnt be so ambitious to pull the spring on a guess, thats some effort|
Id spend more time and focus on finding the problem i love nigels idea of the vacume cleaner extention
Theres alot of other areas that can be rattling and the sound traveling and givimg you a false positive
A few years ago I had the same problem noise from the rear suspension. It took me ages to find, always worse in the summer. Oiled the rear springs and now keep them oiled no noise. I think its rust, gets between the leaves and under acceleration and bumps the spring leaves get stuck and bang when they release. hope that makes sense to you.
|M J Pearson|
|Another vote there for lubricating the springs - and that I was wrong in saying it wouldn't stop the knocking.|
A simple quick test, even simpler and quicker that my previous thought, liberally spray the spring with a lubricant and do the bounce test and if it sounds better then you know its well worth trying the more thorough oiling of the spring(s) to alleviate this problem.
I find a lot of servicing, maintenance and repairs can often boiled down to clean and lubricate/protect.
|been under car tonight managed to isolate it to the front end of the spring re-greased all bushes and pads and oiled spring so it looks like it is the front eye bush I wonder if the bolt has rusted in bush .I will take it off next weekend and have a look will order a new bush and bolt just in case.Can you just drop the front end of the spring down without taking the spring completely off.|
If your lucky you can pull the corrasponding seat remove the 2/4 BADLY rusted bolts and hardware that hold the box that holds the spring and drop down the front half of the sprjng that way
I THINK thats correct ??? Its been alomg time scence ive been in that area
Its not the worst job on the car, but it is a challange and rather micky mousey enginering
A couple of floor jacks and several stands and several 2x4s screwed togather to make a support beam under the back of the car to hold it up are your best friend
Its probably just as easy to jack up the rear, un bolt the rear part of the spring and swing the whole contraption down hinging from the front then support the axle casing and unbolt the front of the spring... which still mifhr involve rwmoving both seats and removing the RUSTED HARDWARE That holds the spring bracket box that holds the spring
As haynes says to assemble, just reverse the order of disassemble...haha (right)
A good 4 inch angle grinder with a thin cut off wheel will come in very useful ... if yku have to go all the way, id replace all the hardware with stainless steel while your there maybe even a little anti seizure compound on the threads of the new hardware
Look into nylock nuts also, they do a great job
Plan a couple days and alot of frustration to do this unless its all been apart recently
|There are 4 bolts to remove from the front spring mount, 2 from inside the car and 2 from underneath into captive nuts. 11 years on since you replaced the front bearing they should come undone if they were assembled with copper ease.
Remove the check strap and then jacking the body up should give you enough clearance to lever the front of the spring low enough to remove the pivot bolt.
Not as easy as working on the bench but the Metalastic bush can then be removed and replaced with a long threaded bolt and various spacers. But if that gets tricky and goes wrong you only have the axle U bolts and rear shackle to undo to lift the spring fully clear.
|I second Guy's suggestion regarding damper mounting bolts, and even if you believe you have found the problem, they are worth checking.
I too had a knocking sound from the rear yesterday, and first port of call were the bolts - as that is what is was last time. Sure enough, the nuts on the offside were loose. Not about to come off for sure, but certainly not tight. I have fitted nyloks so so a bit of mystery why they are loose, but now fitted a spring washer under the nut and plain washer under the bolt so am hoping all should now be well. They seem to require a good deal of torquing up by the very shallow bolt head - as naturally the nuts are difficult to obtain purchase on - and for me, torquing up tight also improves the handling. Another possibilty I suppose is that the hole in the (thin) web of metal to where the unit is bolted to has enlarged, thus allowing it to waggle about (techinical term) somewhat. We shall see.....
Simple enough to check and tighten up by the by, but I had to jam a screwdriver in the front nut to stop it rotating when torquing up the bolt. Could not get a spanner on it.
|Removed spring tonight and replaced front bush and fitted new one with new bolt and washers, gave spring a good oiling and greased all bushes only thing that seemed tight was the top spacer tube on rebound strap so eased that and lubricated it checked all bolts on shock adsorber, I don't think there is anything else i can do now so will see tomorrow how quiet it is now if its not cured it looks like a new set of springs.|
This thread was discussed between 31/07/2017 and 17/08/2017
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