Disco 2 2004 TD5,Air noise on accleratrion & Gearbox (auto) noise but dont think its major

Hi guys just a quick one, firstly im noticing a air sound/ low tone whistle if that makes sence, sounds just like when I had my Fl2 and the intercooler hose had a 1/2 inch cut in it, not enough to realy lag performance or bring lights on but enough to hear, however after a quick look I cant see any splits, are there any common points on D2s where they go? or could it be the turbo im hearing? since it is close to the bulkhead, one min I think its a air leak others I think its turbo, only happens on hard acceleration like steep hills, M-way slip roads etc, seems to drive fine, not fast but it its not meant to be and no smoke that I can see from behind. secondly I did a gearbox oil and filter change (auto) about 200 miles ago and filled the correct way, cycle through gears, into park keep filling till oil runs out, plug in, engine off. However iv noticed once or twice when I switch off I get a sound that's like a pump noise usaly 2 short bursts each about 2-3 seconds long, again, seems to change gear fine, though I do plan on changing oil again in another 300 miles, Old stuff was brown/ dark red, not burnt or smelly just worn. any help is welcome, cheers Richard.

Check your exhaust manifold is not warped and blowing. Look for missing nuts and/or studs. Common fault. Sounds a bit like a turbo whistle at first.

Will do, mines on 120,700 miles that about when they go? Will it affect performance? Guessing it’s just the noise as it’s the waste product escaping. Other than missing nuts/ studs are there anything else to look for on it? Thanks.

Mine went a bit later than that mileage-wise. If you have got it and you are lucky, you will need to take the manifold off, get it skimmed flat again and then refit it, but many of us find ourselves having to do more work drilling out broken off studs, replacing them etc. There are a few threads on here about it including a really awful one which is ongoing at the moment.
If you find this, get back to us and we will help/give advice.

Thanks I’ll have a look if I get chance tomorrow, and post back .

Just looked this morning and all studs and nuts are still there, was going to try and gain access to them to tap or get socket on to feel them but started raining heavy. Also cleaned the map sensor expect loads of gunge but looked relatively clean.

Happy for you, if no signs of black smoke from the edges of the manifold then you seem to have done OK.
However, when you get a moment, it may be a good idea to take the manifold off and slot the webs between each port. This may prevent it warping eventually.
Always a good idea to keep an eye on this. You really do not want it to go wrong.
Cheers, Stan

Just a quick update, got out again this afternoon and had a deeper look couldn’t remove heat shield or try nuts again as it started raining yet again however it did look like a small black, almost oil leak style mark on the top left corner of the manifold, (as in looking at it with fan on the left so cylinder 1?) which I thought could be carbon deposit?

Apart from seeming to have a air leak style noise and sounding harsh about 2500-3000 revs it drives fine, did read earlier that knackered engine mounts cause a rough/ harsh noise. If the manifold is leaking is it something that’s ok to live with for now? Need the car for a 1000 mile trip in two weeks round north western Scotland and think I would struggle to get it off and repaired in time especially as the car is in daily use as my work vehicle. Thanks.

If all the nuts and studs are intact you might be able to get it off and back on again in a weekend, but you won't get it skimmed in that time. As a preventative measure, use Plus gas or your favoured penetrating medium, to help you free off and loosen all the nuts, then copper slip them and put them back on. Then, when you have time you'll be able to do the job without hopefully having to fight them off and possibly break a stud. If one won't budge, don't go for it as you may then well snap the stud.
Sounds a s if you may have caught it in time.
Don't try to tighten up the stud(s) or nut(s) where it is blowing to try and seal it, that'll only make things worse and risk a stud on one end or the other pulling out. Once it has warped only a skim will get it flat again.
Then once you have enough time, take it off get it skimmed, saw through the webs and put it back on. Should last a very long time then.
Best of luck.

Thank you for that, so you think maby just change the gasket for now, see how it goes then with more time take it off get it skimmed? Funny how you mention plusgas... brilliant stuff but seems to be getting harder to find, I got two traditional cans from local motor factors but they didn’t have aerosol, place has since been taken over and now doesn’t stock it. Are there any trick to ease the nuts off if there feeling stuck? I did think about heat but though could that damage the thread inside the alloy head.

Firstly, until you have done your long journey etc, don't even think of trying to take the manifold off, nor changing the gasket. Because firstly there is too much work involved which, with a warped head could lead to things you will have difficulty with, possibly. For example, getting the manifold off the studs. Once warped that will be more difficult. Secondly, a new gasket will make no difference, there is so little "give" in a new gasket I doubt it will seal the gap.

As regards Plusgas, WD40 is probably nearly as good, but when it comes to easing fluid, I make my own, a mixture of acetone (nail varnish remover, old style) and ATF. The acetone will get into the tiniest of cracks and ATF is slippery as heck. The lack of a spray makes no difference, a brush is all you need.

When you do get to taking it all off you may find you need to remove studs instead of nuts, not preferable, but maybe necessary. If the manifold is so seriously warped that it just jams on the studs. You could lever it with some brutality and there are probably those that would advocate that. Personally I would instead try to remove the offending stud or any others that might help. Doing this by liberal, repeated and longterm applications of penetrating fluid, maybe combined with fairly gentle taps to try and break any seals caused by rust or corrosion. Then, in the time honoured way I would make a locknut, with two nuts locked together on the stud to try and gently turn it in both directions. Once it starts moving continuing in the same vein but turning a bit more anticlockwise than clockwise each time until it comes free.
By all means apply heat. It will dissipate through the stud, and the manifold before getting to the head, so unlikely to do harm. Were you contemplating an oxy-acetylene torch, or just a simple butane or propane gas burner? The latter would be fine, although if you can localise and control the fomer I think that might be OK too.
All I know is that so far, for me, you are the first person on this forum to have the leak and still have all studs intact. In which case you should have less trouble than some other members who have and are having terrible troubles with this.
Take your trip then get back to us, we will help.
Bast of luck
Stan

Thank you for the info, interesting about making your own penetrating oil, have heard of others doing same, I’d just need acetone as I have 2l of atf left over from doing gearbox. Heat would just be a powerful propane torch which I’d put my fine burner on, however I do know someone with a small oxy-acet kit should more heat be needed. I did unplug my maf today as it seemed more powerful so going to test that, though still sounds noisy and harsh about 3000revs but Maby that’s exhaust manifold related, would the manifold cause lack of power and increased noise? Also found a 3inch pool of liquid on drive, tasted it as it looked bit orange and was bitter so spent sometime looking for a leak on drivers side but nothing all day, now got paper under it so see in morning, though did just read that bottle caps can give leaks via the blow off/ overflow tube.

rich28uk said:

Thank you for the info, interesting about making your own penetrating oil, have heard of others doing same, I’d just need acetone as I have 2l of atf left over from doing gearbox. Heat would just be a powerful propane torch which I’d put my fine burner on, however I do know someone with a small oxy-acet kit should more heat be needed. I did unplug my maf today as it seemed more powerful so going to test that, though still sounds noisy and harsh about 3000revs but Maby that’s exhaust manifold related, would the manifold cause lack of power and increased noise? Also found a 3inch pool of liquid on drive, tasted it as it looked bit orange and was bitter so spent sometime looking for a leak on drivers side but nothing all day, now got paper under it so see in morning, though did just read that bottle caps can give leaks via the blow off/ overflow tube.

Click to expand...

I just wrote a long reply then went off to find a thread on the same topic and lost my original reply! Never mind!
First, here is a sobering and ongoing thread on this topic.
https://www.landyzone.co.uk/land-ro...ew-cylinder-head-what-am-i-looking-at.352592/
Obviously your problem is nowhere near as serious, but it contains info you will find useful.
Secondly, acetone is used in nail varnish remover, if you do not want to have to hunt down a supplier willing to flog you a quantity of the pure stuff. Mind you, this is real good for cleaning out intercoolers!
Just watch out for "non-acetone" nail varnish removers, little bottles of it are cheap, it doesn't mix well with old ATF but provided you give it a good shake and splash it on straight away it works quite well.
As for heat, the propane tool you mention ought to be enough and if it doesn't work i'd be more tempted to use mechanical ways of getting nuts off: nut splitter, saw, Dremel, drill, etc. And of course tapping the sides of the nut with a pair of hammers to just slightly distort it and break the rust seal.
Once you get to doing the job, don't forget the bit about drilling the holes in the manifold a bit bigger as mentioned in the other thread, as far as I remember.
Brave guy for tasting the liquid! I generally rely on smell! But does sound like coolant. As you say, tank caps can be a cause.
Best of luck!

I think I looked at that post and its sounding like a problem on there.. I know about the different nail varninsh removers as other half uses the acetone free stuff as she claims its better, ill get her to pick a couple of normal bottles up next time shes out. I suppose it would be good on intercoolers as it will clean but dry off fast leaving no residue.

Had a mate call earlier to pick few things up and he used to have a D2 and had the manifold issue so he had a listen to mine and we gave it hard revs on the drive as he watched but couldn't hear anything puffing out or see anything so he reckons the noise im hearing could be on the intercooler or pipes and only when the engine/ induction side of things is under load so next thing befour I go away is put new intercooler hoses on, though a quick look I couldn't see any obvious cuts in them.

As for the liquid I had to taste it as it was over a old oil stain (drive is full of them) and only a bit so could only just see the pinky/ orange colour so the bitter taste confirmed coolant, however last night parked with paper under it this moring it was bone dry and iv marked cold and hot levels on header tank and they have stayed near enough same so im at a loss with that, I think it could be rad beginning to fail as it happened on a old Vectra I had, tiny leak.. stopped.. leaked more.. stopped then constant drip till one day mounting a kerb the twisting of the car just made it give up and blow apart. If it was a hose it would be constant or more under pressure.