Have a drip of clear fluid in front of the oil pan of my 240D. It feels oily, so thought it might be fuel, and it will burn if a paper towel is soaked with it.

Leaks about a drop every 2 or 3 seconds when idling. When I shut the motor off, it actually speeds up a little before tapering off after about 5 or 10 minutes.

No noticeable leaks from primer pump, return hoses or fuel filters. The rear portion of brake fluid reservoir loses a bit over time, but I cannot find any fluid on the cluitch master or slave cylinder. Any ideas??

Thanks!

On the front of the oil pan, or at some distance forward of the pan?

Not many fluids in a 240D
Let's rule out the obvious ones
Oil - wouldn't be clear
Windshield washer - usually blue
Transmission - red

Here is what you could have:
Coolant - clear (assuming the proper G05 coolant)
Brake fluid - clear
Power steering fluid - clear to maybe red if you are using ATF
Fuel - normally has a green to yellow cast but it would look clear as it was dripping.

If it is clear fluid running off the oil pan, particularly on the drivers side, my first guess would be fuel leaking off the injection pump or fuel filter.

Have you tried to smell it?

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2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
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If it is clear and also slippery feeling, check for a leak at your viscous-drive fan.

Dripping off the very front center of the oil pan. Thinking it might be coolant, but wondering why it seems flammable. No noticeable leak from the water pump.

Viscous drive fan. Is that the fan that is attached to the water pump? How could I tell if that were leaking, and what is the fix for that?

Also wondering why I lose brake fluid from the rear section of the master cylinder. There is no noticeable leak on either clutch master or slave cylinder.

Thanx again for any advice.

Have you lifted the caps on anything? It's not like there's an infinite supply of any fluid.

Cut the top off the empty can and wipe the inside dry. Catch some of the liquid in the can but don't taste it.

See if it burns.

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84 300SD
85 380SE
83 528e
95 318ic

If it burns and its greenish sounds like diesel

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He said it burns soaked in a paper towell.

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I'm sorry, brother. I really didn't mean to offend. Paper towels are, well, paper towels. I wasn't clear if having two materials burn while knowing that one of them is a known combustible constitutes evidence that the other is combustible. If you're satisfied then I'm satisfied.

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84 300SD
85 380SE
83 528e
95 318ic

Diesel doesn't burn very well if at all without a wick. Too low a vapor pressure.

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I know the answer is almost certainly no, but does it have self-leveling rear suspension?

Try smelling it then smelling your coolant expansion tank and your fuel cap / filler neck and see if those remind you of how it smells.

It's probably diesel, though.

A little more thought should have gone into it:

dry paper towel will burn

dry paper towel soaked in combustible fluids (diesel, motor oil, ATF etc) will burn longer than dry paper towel alone.

dry paper towel soaked in non combustible liquid will not burn.

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Ever try and light a paper towell on fire soaked in coolant? The fact that it burns at all saturated eliminates certain possibilites.

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Why can't he taste it?

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