Petrol in Diesel

[DITTRICH]

W124 survives Petrol in Diesel

Dear All

Here is an interesting story that has been unfolding since 6.20am this morning.

I had added my 24 year old stepson onto the insurance until 22/4 so he could move some of his gf's stuff from Leicester to Brighton with the E300TD . So he left at 5.50 am and 30 minutes later there is a phone call...

I've broken down at marble Arch (blocking 2 lanes of Traffic - apologies to anyone delayed this morning).
What happened?
Well I filled up this morning at Asda and a while later the engine started working 'not very well' and eventually cut out and now I'm stuck.

So I fumble for GF's phone number and later GF gets his tow man lloyd (good man) to retrieve the car. The Met spotted the car on cctv and moved it out of the way to the Park Lane carpark entrance (thank you).

The interrogation continued by mobile...

So, which precise pump did you use? Did you get a receipt? (no) A slightly more precise description of events ensued and ended with words like 'smoke' and 'would not start'.

Meanwhile my brain is thinking F**K...about 400 times a second, but I manage to keep calm.

I pop over to Marble Arch before Lloyd arrives and say 'hello'. I mention that should it prove 'petrol in diesel' then he is paying for everything - new engine/fuel pump or replacing the car if beyond economic repair.
I never saw the poor lad go so white.

So he accompanies the car to the garage and has to wait...wait...wait until GF can get a look at the car. Meanwhile I'm at work but by 3pm I'm wondering so I start making calls...

I discover that...

1) Entire Fuel System has been drained and flushed.
2) The car started first time after being put back together.

Now, I know that only time will tell, and the young lad will NOT be let off the hook until the car has done another 10,000 miles, BUT I think it is pretty AMAZING that the car still works.

The fuel pump still works. The engine still works. It **seems** okay - touch wood, rabbits foot etc...

In a modern cdi engine £3,000+ for starters - confirmed by GF.

So, I'm not quite as bothered as I was earlier today, and felt it right to share this tale with fellow forumites.

Incidently, has anyone else had a similar experience or 2nd hand knowledge of such things with W124 diesels - I'd be interested in any advice on following this up and keeping a special eye on the car.

Cheers

Les

 

[TKB13]

Quite a story, fingers crossed for you. I would also have the engine oil changed just in case, if not already done.

 

[DITTRICH]

Quite a story, fingers crossed for you. I would also have the engine oil changed just in case, if not already done.

A good point - and one that may well be dealt with over the weekend.
Thanks.
Les

 

[Howard]

Just shows how well engineered the W124's are .......

I imagine in a more modern Merc everything would have fallen to bits .....

God bless the W124's .....

 

[GrahamC230K]

Think it has more to do with the industrial TD engine not a modern CDi Howard!

See, lending cars to people is no good. They will either be motoring virgins and do things like use the wrong fuel or motoring fanatics and have far too much fun in your car!

Hey, this is good family fun and makes the world go round. Glad the car was OK. Just beat him if he looks at the C230K

 

[Howard]

Just messing around Graham .....

We all know already how much better than modern Mercs the W124's are so i don't need to go on about it !

 

[Dieselman]

DITTRICH

Although this episode won't have done the fuel pump, injectors or engine internals any good it should probably escape unscathed.
As Graham has said the older inline pumps are much more tollerant than CDI pumps.

Good luck.

 

[DITTRICH]

The car has completed a London-Leicester-Brighton-Leicester-London over the weekend. It still works.
Thank you for all your comments.
Les

 

[MangoMan]

Les, I did it the other way round. all I did was drain the tank, put some fresh juice on it and I was away. No worries.....

Thanks for the story, good reading.

Ciao, Bill.

 

[Vips]

Agree, the 124's are solid work horses, that just get on with the job, unlike the newer ones!!!

However, From what I have heard, by all means correct me if otherwise, that if you were to put diesel in a petrol engine, than the outcome would be alot more expensive. For some reason, diesel engines are more tolerable if you mistakenly put petrol in the tank than vice versa.

 

[MangoMan]

Agree, the 124's are solid work horses, that just get on with the job, unlike the newer ones!!!

However, From what I have heard, by all means correct me if otherwise, that if you were to put diesel in a petrol engine, than the outcome would be alot more expensive. For some reason, diesel engines are more tolerable if you mistakenly put petrol in the tank than vice versa.

Hi 'Vips'.

look at the message just before yours. I put Diesel in a Petrol. (no one to blame but me though).....

 

[Vips]

oops, DAHH

 

[dougal74]

Might not be a bad idea to use a diesel treatement for a while to add lubricity to the diesel.

My wife put petrol in our A4 2.5 tdi and it was fine after draining (mind you it is the same VAG engine they use in the commercial fleet).

 

[robparker]

i use to add petrol to the old 240td to help with cold starting in the winter,, only a couple of litres in a tank. my 124 diesel always started very smooth so i didnt try it, but MB do make very good diesel engines

 

[glojo]

by all means correct me if otherwise, that if you were to put diesel in a petrol engine, than the outcome would be alot more expensive. For some reason, diesel engines are more tolerable if you mistakenly put petrol in the tank than vice versa.

I would say your wrong.

A diesel engine works solely on combustion. It is the heat of the compressed air that ignites the fuel, whereas in a petrol engine the spark plug has to ignite a highly volatile fuel. Putting diesel into a petrol engine will certainly make you noticed. Loads of smoke, but putting petrol into a diesel, usually gets the bank manager to take notice. It is actually a warranty invalidation issue on modern CDI engines.

Hi Dittrich,
I am surprised your engine is not damaged simply because petrol is far more combustible. The fuel will be igniting as soon as it is leaving the injector nozzle, the piston might still have further to travel compared to the less combustible diesel fuel? Lucky it was not a CDI engine as the fuel is highly pressurised and of course the petrol might play havoc with all the seals.

I would say your engine has been put under an uneccessary amount of stress. Did you tell your step son to use only diesel, or did you rely on him telling the difference between the two sounds?

I think I might be a tad angry with someone (myself or the driver) I suppose I could blame my wife

The engine stopped for a reason?

Sorry to be out of kilter with everyone else.

Good luck and fingers crossed,
John

 

[bolide]

Rtfm

It's worth knowing that the W124 manual - you know, that book that no-one ever reads - gives percentages for permissable contamination of petrol in diesel engines and vice versa. So if you do put a gallon of unleaded in a diesel W124 the book will tell you how much diesel you must add to make it safe

A proportion of Kerosene or petrol in diesel is standard practice in some countries, I believe, for cold weather work

I'd be interested to know if the manual for later diesel engines has any mention of this

Nick Froome
www.w124.co.uk

 

[robparker]

you can (illegally) run a diesel on pure un-treated kerosene. i believe the army use it as a standard fuel for all their tanks, planes boats etc

 

[glojo]

So if you do put a gallon of unleaded in a diesel W124 the book will tell you how much diesel you must add to make it safe

I think we are drifting away from the question. A small amount of petrol will indeed make the diesel easier to ignite. In the UK though we have winter fuels, that make combustion easier.

In the good old days we used an ether spray to make starting diesel engines easier, but modern diesels with the pre-heat do not need any additive.

John

 

[Apial]

I know it wasn't a W124, but my '91 463 300GDL 6 cylinder engine handbook said I could mix petrol with diesel at upto 50:50 in cold weather. It also mentioned kerosene too, but I forget how much.

 

[DITTRICH]

We never did get to the bottom of exactly how much petrol was put into the tank - I suspect almost a full tank.
glojo - he had successfully managed to follow instructions for a fortnight - so it was definitely his fault.
bolide - will check manual tonight and post results.
My considered view is that I should brim the tank and take it for a long run to monitor the fuel consumption. Motorway driving can get 42mpg and assuming this hasn't changed ie +-5% of 42mpg then I guess its still working okay
Rgds
Les