300Tdi Engine Problem Help please...

McBad uttered summat worrerz funny about:

First guess is it's dropped a valve... run it at your peril. You may get away without needing a new head if you don't run it.

I would imagine the white smoke is unburnt diesel.

Alternatively it could be the head gasket which should be evident by a rise in temp and water being AWOL from the coolant system.

I'm no expert and have consumed 3/4 of a bottle of wine. Hope you get it sorted! I can recommend a good wine if all else fails!

Lee D

Lee_D uttered summat worrerz funny about:

Just another thought... Sis had a diesel horse box that sucked air in on one of the cylinders... that resulted in white smoke too.

Lee D

Hmmmm....

I agree white smoke looks like unburnt diesel. AA man and I thought probably not a blown head gasket; temperature is normal and stays normal and water levels are all normal and not changing.

Although I don't expect any recourse to the garage I bought this disco from a few days ago they did mention that they 'had done the tappets' as part of the pre-release service and putting a fresh MOT on it. Apparantly their mechanic is ex-Land Rover so should be competent... but could that be a 'clue'?

What happens when a valve 'drops'?

I'm going to have to drive it, if only briefly, as it is sat in the end of the driveway blocking in my 17 year old TDi 90 which IS reliable transport.

Thanks,

M.

Sounds exactly the same as a customers one I had in last year - ran fine for

2 or 3 days and then started playing up ................... AFTER FILLING WITH PETROL!! Because it had ran ok for a few days since last refuelling, we discounted that as a likely culprit in much the same way as you have done, we even considered the injector pump at one point and possibly one or more choked injectors due to the injector pump breaking up internally and sending the swarf up the pipes to the injectors. In fact, it had me so stumped at the time that I asked on this ng for any ideas as I'm more of a petrol-head than a disiesel dipstick. ;-) Maybe worth draining a couple of filter's worth out to confirm? Badger.

I would immediately lift the rocker cover and have a look in there, you may see the problem instantly, and if they had "done the tappets" I would be wondering *why* if it was running ok and they were selling it. Check the rocker/pushrod/valve/cap/spring etc and if you see a problem don't fix it without consulting where you got it from, just replace the cover and ask them to fix it.

If he is " ex- Landrover " then why is he not still working there?

It can cause a lot of damage to the head, block and piston etc.

Martin

Take off the fuel filter and check whats in their, diesel or petrol??

Well if Badger's diagnosis is right then this is just what you would expect from pinking of petrol in a v high compression engine.

AJH

Thanks all....

Where does the fuel pipe pick up from... what depth within the tank?

Reason I ask is that when I bought it I immediately filled the (already one third full) tank and I remember checking very carefully that I was using the diesel pump...

If the tank had at some point been filled with petrol and there was a layer of petrol floating on top of the diesel would it be possible that that somehow to have come in range of the pick-up pipe..? I'm not convincing myself because the tank is now down to about a third full again and if pick-up pipe was at this level then how would the last third of the tank ever get used... Also, I'd expect the petrol and diesel to have mixed through the vibration of normal driving and not to get this very sudden onset of symptoms.

However, I will try draining off some fluid from the fuel filter and see if there is anything odd looking / smelling in there. (Fuel filter was also replaced during service... I'm beginning to wonder if they were struggling to get it through the emissions test for the MOT or something and just kept changing service items and doing tappets until it went through...)

The AA man and I both wondered if it was a fuelling problem. The noise though is not pinking. I did put petrol in my wifes diesel focus last year and the rough running sensation is very similar to what happened that time on the M6, but it does mean that now I always look at pumps very carefully!

Any more ideas welcome. When I discover what the problem is I will put a note up.

Thanks everyone. I will be in contact with the garage from where I bought it. :o)

Malcolm.

Unlikely as diesel is miscible with petrol doesn't the 300 have a sedimentor in front of the tank possibly you have a 'jellyfish' ( not joking btw, a group of organisms that live between the water and diesel ) which requires removing the cup and pouring the little sod out 'been there done that'.Another interesting possibility is that one of the valve stem caps has popped off - small pads that sit on top of the spring under the rockers leaving an excessive clearance.Drop me an email ( take out the meat product reference first ) and I'll post you back the Land Rover 300/200 tdi poor running diagnosis flow chart and bulletin a 190k pdf file and anyone else who would like a copy

Derek

It could well be - if a valve stem cap has fallen off the "timing" for that valve will be way out. As said in another post, get the rocker cover off and chack for all the tappets not being loose.

Richard

UPDATE....

Lifting rocker cover revealed a broken rocker arm, which explained all the symptoms. Effectively the vehicle was running on three cylinders. However, replacing the rocker arm and setting the cam- shaft back up again still leaves the vehicle running very rough.. There is clearly more to this...

Apparantly broken rocker arms are very rare and usually only happen when a cambelt breaks. Garage are going to carry out further investigations / work and in the meantime I remain discoless. :o(

I'll let you know the further instalments...

Kind regards,

M.

McBad uttered summat worrerz funny about:

I'd be concerned now incase the rocker broke in such a position that the valves were left open on the relative cylinders. May be worth a quick compression test on those cylinders before whipping the head off if you have the kit available.

Lee D

If the valve spring is OK, could it do that ?

Steve

More likely piston hitting valve would weaken rocker arm??

AJH

I expected such a problem. Is the garage carrying out the investigations the one where you bought it from? If they have done something wrong when they 'set the tappets' then it's only fair that you should leave it with them to rectify the problem as they will also want to know what caused it. I would think they would sort it no problem if only for good customer relations.

Martin

On or around Sun, 13 May 2007 12:23:44 +0100, Steve Taylor enlightened us thusly:

No. More likely a timing belt failure, causing a piston to hit an open valve and break the rocker.

Mind, it's better that it does that than punching a hole in the top of the piston or bending the conrod.

Good point - misread / intertpreted the post as a snapped cam shaft...

Lee D

Hi, no the garage carrying out the investigations / repairs is my local specialist, whom I've used for several years now and who's work / opinions I respect. That is not to say that I don't respect the work or opinions of the garage which sold me the vehicle; the issue is that they are a very long way from my home address (~100 miles) and I had no way of getting a dead vehicle back to them. Ultimately I need it fixed... I'd have preferred to give the car back to the selling dealership but it just wasn't practical.

Anyway, both garages are talking to each other, we are all curious as to what is wrong here.

I don't think the garage which sold me the car had any intention of selling me a dodgy motor!

Kind regards

M.