Horrible noise from my poor old E32.

[Turbo-Brown]

Sounds like this:

http://s225.photobucket.com/albums/dd29 ... V03887.flv

I'd hoped it might be something simple like a misfire dumping fuel into the exhaust, but I've gone through and eliminated that extremely optimistic option.

It's a 740i, K reg.

The odd thing is that when the engine's warm, the noise all but goes away until it's just above idle.

Any help or indeed comiserations gratefully received!

Noise doesn't go away when you're in D, R, or indeed any other selector position.

[oakey]

Thats well wierd Sounds like a stone inside a tin can Takes away from the lovely v8 burble a bit

[Turbo-Brown]

Even more odd the way it suddenly stops making the noise and then starts again, never done that before.

Was gonna check the oil level in the gearbox or something, but in their infinite wisdom, they left off the dipstick from this model!

Occurs to me that it's got to be coming from between the engine and gearbox as the input shaft stops turning when you're in a gear which would eliminate the gearbox itself as the noise continues.

Mabey a torque convertor bolt's come loose or something?

It still drives fine, just a bit embarrasing. Also more than a bit worrying that it'll suddenly stop working or the wheels will lock at 70mph or something

[Yaninnya]

Hi Alex,
Happy Chrismas!
Did you checked the exhaust mounts? Specialy these on gearbox? Nothing broken? Hit each silencer and cat by hand (or rubber hammer). It is souds like broken cat ceramic insert. If not, check the torque converter bolts. I'm not sure on M60 but IIRC it has the special hole (with rubber plug) in the engine sump as M70/M73 to get to these bolts.
I hope this helps a little.
Jan

[Turbo-Brown]

Hey Jan, How ya doing?

Happy Christmas to you too dude

I had wondered if it might be collapsed CATs, and if you tap the exhaust system it does make the same kind of noise.

I'll get under there with a rubber hammer tomorrow and see if it replicates the noise, fingers crossed!

I really hope it's not gearbox / torque convertor related!

[320ise]

read somthing a while ago about these, is your oil pressure effected or light on longer than it should be when you first start? if so remove the sump, check the oil pump bolts inside, and you may just find that one has come out or is on its way, bmw do have replacement bolts as i hear this can be quite common, mite be a long shot but sounds like thats what it may be to me.

[bubbazenetti]

My guess is it Its the catalytic converter falling to bits inside.

Ive been dreading it happening to my 540i.

Hope you have a good boxing day anyway.

John.

[Turbo-Brown]

I had thought of the oil pump bolts, but the light goes out within fractions of a second of the engine starting so I think that's all doing what it should.....I hope!

The noise is only really loud from underneath/beside/behind the car, with the bonnet open it doesn't seem to be enginey.

If it has to be one of the engine, gearbox or CATs, I'd rather it be the CATs as I've got a couple of new universal metal substrate ones kicking about at my parents which I could weld in. Who knows, might even get another 0.00001bhp too

It really is a loud and horrible noise for the CATs to be making. Anyway, will break out the hammer tomorrow and see if the noise can be replicated with the engine off

I do wonder if it's had some cylinders not firing though which might've killed the CATs. The idle was pretty silken, but I had all the plugs out today and they all had MASSIVE gaps! Really needs a new set of plugs but as an interim fix I re-gapped them all and put them back in. It now idles so smoothly it's unbelievable!

[Yaninnya]

Hey Jan, How ya doing?

Not bad, only one german eBayer roll me. He sold me crappy engine block (not mentioned in auction description) and do not want to refund anything (and it is quite rare one; only 202 was made ). He only don't know that I'm wery consistent in everthing what I'm doing and internet scams are very seriously for local police in Jersey.

I had wondered if it might be collapsed CATs, and if you tap the exhaust system it does make the same kind of noise.

So you can be 100% sure that your converter insert is cracked. Take it off, bash it, put everthing back together and job done.

I really hope it's not gearbox / torque convertor related!

It is not. If you are taping the exhaust and it does the same noise, it can't be the convertor (as I understand, you're tap the exhaust when engine wasn't running).
Jan
PS: Do you know any company which can repare Alusil bore for sensible money?

[Turbo-Brown]

Will do the investigation tomorrow (in the cold and wet ) keep everything crossed for me guys!

Take it your block has buggered cylinder linings then?

I saw years ago a company who could re-line Nikasil bores, but I can't remember for the life of me who they were. They were mentioned in a magazine called Practical Classics. It might be worth sending them an e-mail to see if they still know or whether there's anyone else who can do Alusil.

[78dude]

Yea its the CAT who is ripping its self to parts inside the pipe dude! Its a ceramic thing who is loose so you need to replace it!

[nickso]

Yea its the CAT who is ripping its self to parts inside the pipe dude! Its a ceramic thing who is loose so you need to replace it!

nah, thats going to be pricey.

just cut a hole in the cat and pull all the insides out. then weld her back up.

[Yaninnya]

Take it your block has buggered cylinder linings then?

The valve droped in one of the cylinders in right bank. I don't know how it hapened as it is first of these engines with droped valve which I heard about. It look like valve guide slips down and valve hit it and broke but still don't know what was the reason of it. The bits of the valve gone to other cylinders in that bank thru inlet and damaged other bores and pistons. I bought the pistons already but the second block which I bought to replace damaged one is crap. So I need repare the first one as it is very unlikely to find another block (Alpina made only 202 of them).
Thanks for that info I'll try to find them.
Jan

[Ant]

for getting the bores replated, try any local 2 stroke tuners, they should have a local source, alternative is get the liners bored for steel inserts, not a cheap process though.

@ Alex, I'd go for cats over anything else , cut em out

[Turbo-Brown]

Now what's the score with Cats?

There's no real way for Mr MOT man to check the matrix is in there (if the cans are present). Wonder if it'd still pass emissions.

Anyway, After all my tinkering with the plug gaps, I drove to my parents today and the engine stalled every time I stopped I ended up left foot braking so I could keep the engine alive all the way back.

New set of plugs has cured it though, and made the idle even smoother.......and (temporarily) made the noise go away. Aah, twas a blissful 15 seconds of peaceful motoring!

[nickso]

Now what's the score with Cats?

There's no real way for Mr MOT man to check the matrix is in there (if the cans are present). Wonder if it'd still pass emissions.

it might still pass. i know its a bit different but the g/f's fiesta had the cat removed and plated back up and it still passed emissions, the guy asked if id removed it cos he noticed the welding. i told him it probably had been removed and he said he didnt care as long as it passed. probably different for each tester though and he always gets my mot business so he maybe didnt want to rock the boat.

[Yaninnya]

for getting the bores replated, try any local 2 stroke tuners, they should have a local source, alternative is get the liners bored for steel inserts, not a cheap process though.

Hijacking the thread is not my intent (sorry, Alex!) so maybe it is good idea to split it to separate thread.
The original pistons has special coats for Alusil so with steel inserts I need new twelve pistons so it is not a cost effective option.
Do you know any 2 stroke specialist which can recoat Alusil block or know who can do it (I'm located in Jersey and island is too small for even one real mentioned specialist)?
Jan

[stonesie]

Now what's the score with Cats?

There's no real way for Mr MOT man to check the matrix is in there (if the cans are present). Wonder if it'd still pass emissions.

If it looks like a cat and it passes emissions then the mot guy will be happy, to do it stealthy, take the cat off and bash the innerds out of it with a metal bar and a hammer.

Collect the remains in a bag and your local scrap merchant will give you some beer tokens for the precious metals