Drain the fuel tank

[lulu]

Hi All,

Yes it's happened. After riding around and getting used to putting unleaded in the bike....... I went and put the same in the C220cdi.

After reading all the other threads on the forum on what to do I'm suitably scared into draining the tank. (20 litres into a complete refill I realised I was using unleaded, then completely filled to the brim with diesel and drove home gingerly)

Having a look around underneath I can't see an obvious or easy way to drain the tank.

Does anyone have any information on the easiest way to drain the thing?
It's a W203 coupe (CL203)

I'm currently syphoning, but the only pipe I could get to go round the bends is 4mm nylon capillary! It's been 4 hours already and only 20 litres has come out. (Damn sure it's not the 20 litres of unleaded either) There's also no guarantee that the pipe is sat on the bottom of the tank. It'll probably stop just as I go to bed!

Thanks in advance
Lulu

 

[Ellsy Tanners]

Remove the pipe that feeds the fuel filter, then extend it so you can get it into a container.

Then switch on ignition, the fuel pump in the tank will run for about 20 seconds, and fuel will flow from this pipe. keep switching ignition off and on untill no more fuel comes out.

After this you still need to remove the tank senders under the rear seat to mop out the tank.

 

[television]

A CDI is not good to have 30% petrol owing to the high pressures used in the systemand the only lubrication comes from the diesel.. I would not drive it until its out

 

[Xtractorfan]

You wont have to mop out the tank after its drained fill with good quality diesel and off you go..remember to replace the fuel filter and refill the filter with diesel

 

[lulu]

Thanks Team, fantastic late night advice.

Ellsy, I'm currently doing the ignition on/off thing and the first 'on' yielded a good 10 litres or so of fluid. Subsequent sequences seem to be yielding less each time unless I leave it for a few minutes between goes. There's still 1/2 to 1/3 of a tank full and I'm only get a bit of a dribble. Do you have any thoughts on this?

I'm going to pop off down to get the fuel filter now and therefore will have left it a bit longer before commencing again. I'll post an update on my findings with the amounts per on/off sequence.

Thanks again
Lulu

 

[colechelle]

as normal from the site some good advise, the only way to drain a 203 is to remove rear seat, each side there is 2 plates held in with 6 8mm bolts, remove, your then faced with two caps, we have a special tool but you can tap them round, near side is one gauge, off side is pump, you have to suck out both sides, if you use pump to pump out or suck out of line to engine you will still have a full pot of fuel, the tank is in two parts, doing it the way that has been said will only drain one half of the tank!!!

 

[lulu]

Couldn't get anymore to come out without putting more fresh diesel in! This is still with the diesel guage reading approx 1/3 full.

Got a new fuel filter from MB and spoke to the very helpful guy there who told me the official MB line (ie replace everything in sight) but said in reality if it hasn't gone bang I should be OK if I clean it down as best I can and replace the filter.

With my rough calculations I managed to get 2/3 out at the first attempt then repeatedly diluted the remaining 1/3 with a Jerry can of fresh diesel to leave me 20 litres with approx 15% of petrol in it. Drove it a mile to fill up with fresh diesel to hopefully leave me with 60 litres of approx 5% petrol.

I'm going to keep topping up every 100 miles to continually dilute it to negligible amounts.

I can understand 100% petrol and you can kiss it goodbye, but 2/3 diesel and not enough lubrication, that's really very scary. I don't know how clean forecourt tanks are these days but in my youth when I had a job serving fuel to customers all sorts of muck (mostly water) would be dragged up from the bottom of the tank. Goodness knows how many people had semi-grotty fills before the one that wouldn't work!

I've now got approx 60 litres of contaminated diesel. If I chuck it in the heating oil tank (3500 litres) it'll be so dilute it'll......... No don't do it, quit while I'm ahead.


This will not happen again!

Just composed this as Colechelle replied!

Colchelle, how does the other half ever get to the engine?

 

[colechelle]

hi mate, sorry to hear of your mistake, seems im doing about 5 to 6 of these a week, if you do as i said you will see that the pump is on the o/s pot but the fuel comes out the left hand pot, the tank is one piece but shaped so the prop can go under, it works on pressure while the engine is running, just read you reply, what you have done now by driving the car is mixed 1/3 petrol to derv, i wouldnt start that again,£400 for high pressure pump, £200 each injector, think you can see where i going with this, you need to get both pots as empty as you can. be on here for a while if i can be anymore help, cole

 

[Xtractorfan]

I reckon he should get away with it,he's already syphoned 20ltr from the right hand pot.. filler side? and pumped the other, and i do know of a few garages when they get this problem on any cars they add some lube and drive em and refill them.. I wonder would flushing oil be the cure here ........ add it to the petrol.......

 

[hmang]

bung some motorcycle 2 stroke oil in for the lubrication.

1 litre treats 30 - 40 litres of petrol

castrol tts or other for moto cross

 

[jamesmc]

bung some motorcycle 2 stroke oil in for the lubrication.

1 litre treats 30 - 40 litres of petrol

castrol tts or other for moto cross

Sounds like the most obvious simple fix to me. I'd go with that.

 

[lulu]

My only concern with the 2-stroke oil is what it will do to the particulate filter in the exhaust. How different is blueish smoke to black soot where the filter's concerned?
(Don't wish to appear paranoid - but I am - I don't suddenly want to be starting a thread, 'How do I clean my particulate filter?')

I'm very appreciative of all the advice I've received on this matter.
Thanks again
Lulu

 

[colechelle]

Your quiet right to worry but the filter can take a good hamming, had a turbo go the other day on a C220 and filled the filter and exchaust up with neat engine oil, removed and steam cleaned out, after about 10 min fast idle and new turbo smoke had gone, would still go with drain out, only way to make sure its right!!

 

[spida505]

Has a C220 cdi (2007 reg) got a split tank as I can only find one sender unit cover under the back seat?