i think my discovery is dead

a quick update I have just had a look at the coolant and it looks to be oil free. I half expected it to be mixed with oil, i know that this is not exactly a high tech check. GGJ

I seem to recall something about this happening when oil starts feeding into the engine and it fuels itself on oil, hence the runaway as there are no controls over it

Can anyone help me out here?

BTW - Where are you Gary?

Si

"Gary G Jones"

Nope

It won't. You will be lucky if it runs at all, but if it does it just might be OK

Unlikely.

What has happened is that your intercooler has gradually filled with oil and it started to siphon over into the air intake. If not then oil has been overfilled in the sump or diesel has added to the volume in the sump. My money is on the first reason. This would probably have happened due to a failure to maintain or just a failure of the cyclone which separates oil vapour out of the breathing system so that it the oil is returned to the intake rather than returned to the sump. It used to be the case that cleaning the intercooler was a regular service item, both to maintain its efficiency and to prevent it filling with oil.

Huw

On or around Thu, 25 May 2006 19:10:01 +0100, "GrnOval" enlightened us thusly:

sounds like it. can happen if the sump gets pressurised by e.g. a head gasket leak - oil blown into intake, through that tube they helpfully put there for the purpose, revs increase, pressurise more, etc.

this is the most likely runaway - have you checked the dipstick? any oil on it?

The best way of stopping it is to block the intake, but to do that you have to have access to it. You can sometimes do it by putting it in top gear, standing on the brakes (not handbrake) and letting the clutch in (steadily, don't jump off it or you might rip the engine out), but that might just add a burnt-out clutch to your woes.

I doubt the engine will have survived this unscathed - you at least need to lift the head and probably replace the gasket.

The last engine I heard of doing that was a R*****t tdci when it was overfilled with oil, started running on its own innards and blew itself to smithereens.

Assuming that you have not just topped up the oil you need to check the oil level first. If this is OK, check the crankcase breathers, make sure that the engine has not pumped its sump into the air intake, check the inlet hose for lots of oil.

BEFORE you start the engine again, make sure the intercooler is clear of oil or it may just rev itself to death again,possibly with a catastrophic conrod failure etc.

because the fuel is regulated by the diesel pump you should not have too many problems on that side but just check that the governor seals are intact etc. If the engine has revved up massively it is usually running on its own sump.

Ben

There are a couple of kill quicks you can prepare for;

1. Locate the fuel pump, identify the feed from the tank (not the one going to the dis pump) crack it open then tighten back up (finger tight), then when you start the engine be prepared to leap in and undo it. the engine will continue to run until there is no fuel.

1. At the back (bulkhead side) of the distributor pump there is an electrical connection. Turn on the ignition go to the pump and remove the connection if there is a noticable click (repeatedly do this to check) you have found the stop solenoid. this can be removed when the engine is running. the engine will stop providing this itself is not at fault.

2. If an EDC system the same should apply, but I would check all connections for the accelarator (drive by wire) connections as these may be at fault.

Hope this may help, experts welcome to castigate

|| The best way of stopping it is to block the intake, but to do that || you have to have access to it. You can sometimes do it by putting || it in top gear, standing on the brakes (not handbrake) and letting || the clutch in (steadily, don't jump off it or you might rip the || engine out), but that might just add a burnt-out clutch to your woes.

Not that easy - it's an automatic.

Gary G Jones wrote:

|| Hi Folks || Just driving home in the discovery tonight (300tdi 1995 auto) || maintained regardless of cost. || I even spent out on it yesterday, having new discs and pads fitted || to the rear. || Anyway, about 6 miles from home , already covered about 20 miles, I || noticed a lack of acceleration while pulling out of a junction, hmmm || ,strange I thought , took it nice and steady and then noticed a bit || of smoke coming out the back looked to be grey in colour. || I pulled over and had a quick look under the bonnet, nothing obvious || so I carried on. The smoke out the back was now worse and the power || was down even more. || As I arrived outside the house I switched off but the engine kept on || running. Worse than this it, decided that it was going to rev itself || to hell and back ( I have never seen the rev meter go that far round || before) and smoke out the entire street, that much smoke that a || neighbour came over to see if I was OK and did I want them to call || the fire brigade out. The discover has about 115000 miles on || the clock now and like I say, || since I have owned it for the last 35000 miles I have had everything || checked ,serviced, and replaced when needed and sometimes just to be || on the safe side. || So my question is, || 1)where do I start to look for the problem, does it sound to you || folks like a head gasket problem. || 2) if I to turn the key and start it up and it goes into super high || rev mode even with the key out, how the hell do I stop it fast. || || I'm just going now to have a look at the coolant to see if its full || of oil. || || Many thanks for your help. || GGJ

What all the others said. It sounds like it is running on its own oil. At that mileage, it might just be the bores are worn and the cylinder pressure blows past the pistons and pushes the sump oil up into the air intake. If you'd overfilled it with oil, that might have made it happen more easily. With an auto, the only reliable way to stop it would be to get access to the air intake (quickly) and stuff a rag down it to choke the engine. I wouldn't risk putting my hand over it as you might with an engine running normally. If you're doing any "testing", take the air filter off and dismantle so you can stuff something in there if it does it again.

I'm in sunny Norfolk, well it was today anyway, then it got very foggy and smelly when the disco went nuts. GGJ

You'll want more than a rag - that will just get sucked straight in to the turbo causing damage. The best way is a square of sturdy plywood to put straight over the intake pipe.

Or the seal in the turbo has let go and it'd pumping oil in via the turbo.

If a diesel engine is running on the contents of it's sump none of your suggestions will help. the only option is to block the air intake to the engine.

Sounds like the classic running-on-engine-oil syndrome with an outside chance of a failed/jammed injection pump.

I had an old Land Rover with a Perkins 4203 (ok, a million miles from a

300tdi but same principle) and I decided to put some fuel cleaner through it. All the semi-solid sediment loosened off, jammed the filters and also jammed the injector open. The result was a severe loss of power because it couldn't draw enough fuel coupled with a tendency to rev like made in neutral.

Check the oil level and also the consistency. Give it a sniff to see if it smells of neat diesel oil.

Well I have had another quick check of things, the dip stick is still showing oil in the sump, the discovery had a 12k service about 800 miles ago, no top up of oil since then, it uses virtually no oil at all and never has. It does not even leak any oil. All turbo hoses were changed for silicon ones about 1500 miles ago, not much muck was found in the old ones. I think, going by all the posts I will give my local land rover specialist a call tomorrow and get the AA to take it over to them. To be honest I have lost the nerve to switch it on. I had read about this revving thing a few times but my god, I sure don't want to be standing next to it if it does it again. I don't think the neighbours would be too happy either. Many thanks for all your suggestions. I will let you know how I get on.

Cheers GGJ

well, if you're stuck i've got a v8 auto sitting on the drive doing nothing- we're in kent

Si

Could the loss of acceleration earlier in the journey have been the turbo bearings failing - loss of boost, turbo oil seals getting stretched causing the smoke from the exhaust, finally the high pressure oil feed to the turbo bearings squeezes oil past the seal and into the inlet?

I've seen it before on diesel turbos.

Andy

1986 110 V8

Gary, are you in West Norfolk by any chance? There's TJC between Swaffham and Fakenham or Overland at Methwold. TonyB

On or around Thu, 25 May 2006 20:45:56 +0100, "Richard Brookman" enlightened us thusly:

yer right. in that case, you have to try and block the inlet.

Hi Tony , yep I'm in west Norfolk, and it will soon be heading off to TJC's to see what they say.

GGJ