Geodark

Active Member
Evening all, I am getting a strange intermittent knocking / rattling noise but I cant track down where its coming from. Sometimes it sounds like the front, sometimes the back, can't work out if its brake related, steering related or clutch related - but it does seem worse when turning and sounds as if something is rattling in the wheel. But as said, it isn't every time. I did a u-turn and all was fine then later turned the wheel a bit to drive onto my drive and it rattled a bit then was fine.
It isnt a grinding or crunching noise, definitely a rattle or knock.

What kind of noise does the VCU bearings make?
 
Took the neighbour for a ride and he is convinced its coming from a rear corner - what kind of noise do you get from the brakes when the spring clip goes? and could a noise from the back really sound like its coming from the front sometimes?
 
Probably the rear diff front mount. They perish with regularity.

Possibly/probably assisted by a tight VCU - so a 1 wheel up test is in order.
 
Probably the rear diff front mount. They perish with regularity.

Possibly/probably assisted by a tight VCU - so a 1 wheel up test is in order.

Cheers GG, will give it a check at the weekend - will leave it parked up until then - did it about 6 months ago and got 30seconds, can they change that quick? oh and I forgot to say - it isnt something that has come on gradual - noise came on suddenly a couple of days back.
 
Going to be having a look at this this weekend depending on the weather, can these mounts be visually checked while in place or am I going to need to drop it all to check? Neighbour (a mechanic) had a quick drive round the block and is convinced its coming from the rear - we are going to get it up on the ramps this weekend and give it a once over. Leaving her parked up on the drive until then - dont want to make things worse :)
 
can these mounts be visually checked while in place

It's pretty obvious when the diff mounts have failed. The rubber part visually splits, so is easy to spot.

Make sure you do the one wheel up test and check you have 4 identical tyres fitted with least worn on the rear. If the VCU is stiffening or you have odd tyres, then the failing diff mount is a sign of overloading.
 
It's pretty obvious when the diff mounts have failed. The rubber part visually splits, so is easy to spot.

Make sure you do the one wheel up test and check you have 4 identical tyres fitted with least worn on the rear. If the VCU is stiffening or you have odd tyres, then the failing diff mount is a sign of overloading.

Yeah Nodge, got my bar and weight ready for the weekend, last check (about 6 months ago) was around 30 seconds from memory, but that was on a warm day. Had her just over a year and the first thing I did was to stick 4 new identical tyres on. Even got a tyre pressure monitor so I can keep an eye on them :) She has only done about 3000 miles while I have had her, mainly use her when I head out fishing or when I get bored with the Astra haha.

Anyways I will get under her at the weekend, Saturday looks good, and then report back on here. Debating as to ordering a set of diff mounts just in case.
 
Well we had a look and the front rear diff mount was indeed shot - so we replaced that and... the knocking noise is still there - going to get back under the car this weekend and do some further prodding and pulling to see if we can track down what's going on.
 
OWU finally done and... around 30 seconds from 45 degrees to 0 which I reckon is ok. I will post a video up on youtube later in case anyone wants a peek.

Anyway we spun the wheel back and forth and there was knocking from around the VCU though and when we had a look there is a bit of play - so looks like the UJ is bust. Also the VCU mounts are shot - never noticed how bad until my neighbour was pushing on the prop and I could see the movement. So the whole thing is coming off and I figure if I am on replacing the vcu mounts and ujs I am thinking I might as well replace the VCU at the same time even if the timing of the owu looked ok - whats everyones thoughts?

This is the youtube video, I reckon the VCU looks ok - whats everyones thoughts? timing is more or less the same as it was last year.

 
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How long was your lever, to where the weight was hung? It should be 1.2 M for the timings to make sense. Yours looks slower than mine, but I didn't time it. :(

Up to you where you go from here. If you replace the VCU, then you'll be starting afresh, which can only be good. ;)
 
This is the youtube video, I reckon the VCU looks ok - whats everyones thoughts? timing is more or less the sa
How long was your lever, to where the weight was hung? It should be 1.2 M for the timings to make sense. Yours looks slower than mine, but I didn't time it. :(

Up to you where you go from here. If you replace the VCU, then you'll be starting afresh, which can only be good. ;)

yeah, I plan on keeping the car a while, I know the VCU bearings are shot - the UJs have a bit of play so I figure that since I need to take it all apart and since I plan on keeping her a while I might as well do the VCU at the same time. Just need to convince the boss that I need to spend the £300 doing it haha. She normally says "If you are spending that on the car or fishing then I get the same in shoes" so I guess thats a few pairs of shoes she will be ordering . :)
 
If that was 5kg at 1.2m I would be happy to keep it for a while longer. A bad VCU will take closer to 2 minutes so either it has been really well looked after all its life or has been replaced sometime already.
Or your mileage is low. ;)

And she's already got enough shoes. :D
 
Its 1.2 long, but 6kg - so its a bit heavier. Dont know about the history as the place I bought the car from got the car from auction, but the auction place sent the wrong service history. This was supposed to have full service history according to the auction house but the place I bought it from never got it. I got a few hundred quid knocked off due to this, so I can't complain.

Anyway was just thinking if I need to strip it totally I might as well do the VCU and the if I have any problems then I know its the IRD or rear diff. Hopefully the new VCU, bearings and UJs will sort it, and if I am keeping the car then they will need doing at some point haha.
 
Anyway was just thinking if I need to strip it totally I might as well do the VCU and the if I have any problems then I know its the IRD

Your VCU has a some life left in it. But if you get one from Bell, it'll come with bearings, if you specify it too. This will save some money and time messing with bearings yourself. ;)
 
Well thats the prop and vcu off, just waiting for all the bits to arrive before I get it sorted and stuck back on again. Just hoping the noise has gone when it goes back on and it isnt anything to do with the IRD!

Going to have to get the wire brush and rust eater on her soon as well, starting to look a bit rough underneath in places.
 
Just hoping the noise has gone when it goes back on and it isnt anything to do with the IRD!

Change the oil in the IRD. You can also get a good idea of the condition of the IRD, by looking at the oil that comes out. If it's black, then it's most likely to be fine. If it's grey in colour, or has silver flecks in the oil, then the IRD needs a rebuild.
 
Change the oil in the IRD. You can also get a good idea of the condition of the IRD, by looking at the oil that comes out. If it's black, then it's most likely to be fine. If it's grey in colour, or has silver flecks in the oil, then the IRD needs a rebuild.

yeah was planning this, have ordered myself a decent set of hex sockets as i hear the plugs/nuts on them are like butter
 

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