Diesel leak fire danger - PeachParts Mercedes-Benz Forum

jiggs2006 · #1 10-25-2006, 05:44 PM

I have diesel fuel dripping from at least one hose under manifold near top of injection pump, causing dripping against lower side of engine, and down to the protective pan under the engine. How likely is this to cause a fire while I'm waiting for appointment to get it fixed? I drive the car about 20 miles a day.

jshadows · #2 10-25-2006, 06:19 PM

I'd say pretty darn low. I had diesel spewing all over the underside of engine for about 500 miles on a trip to New Orleans due to a semi-ruptured hose to the IP with the major problem being a mess and pretty bad fuel economy.

benzforlife · #3 10-25-2006, 06:23 PM

yeah, diesel is nothing like gasoline, yes, it is flammable, but it nearly takes an open flame to ignite it, or extremely high heat, which hopefully in ur case isnt happening under ur hood, so i wouldnt worry if its getting fixed!

vstech · #4 10-25-2006, 10:45 PM

uh, my 82 SD has leaked around the Prechambers for 6 months of continous driving. the worst problem I have is it causes clean spots on the engine and drips the grime off onto my driveway.
no worrys.
John

Mustang_man298 · #5 10-25-2006, 11:04 PM

Although I am not so naive as to try this myself, I have seen a few diesel mechanics brag to me in earlier years about how hard it is to light diesel fuel, and demonstrated it by satsfying their smoking addictions while working on the fuel systems. I don't recommend it as practice, something about that common sense bug still gets to me...

I had a return line fail on my 240 while letting it run in the driveway to charge the batts and keep things lubed (wasnt on the road yet) and it sat that way near a half hour, just had a wet spot on the ground.

Matt L · #6 10-25-2006, 11:08 PM

We had a '85 Euro 300D sitting outside of a garage fire. The front of the car was completely toasted; no paint left, no windshield, the works. The fire department guys looked under the hood and saw the stream of fuel coming out of one of the lines (which was not completely burned up) and asked if the car was gas or diesel. I told them it was diesel, and they had no further concerns.

The stuff won't burn if you throw a lit match into a puddle. If you have a wick in the fuel, the wick will burn, as will kerosene. The fuel isn't volatile enough to support a flame without a something to form a wick.

Shorebilly · #7 10-26-2006, 07:58 AM

G'mornin' Folks,

Diesel engines, in general, have a fuel side and an exhaust side. This is a design consideration to limit the possibility of high pressure fuel squirting onto hot exhaust manifolds and turbochargers.

Diesel fuel will burn readilly if heated.....and will autoignite if heated to it's specific autoignition temperature.....428 - 572 F......which is easilly reached by a diesel under load exhaust temp...

http://www.omega.com/temperature/Z/pdf/z128-130.pdf

As long as your diesel leakage is not getting any hotter than engine block (cooling water) temperature, then you should not have any major fire hazard!!

However, it is still prudent to repair any fuel leakage from both an economical and safety viewpoints....

SB

vstech · #8 10-26-2006, 08:12 AM

that is how MB engines are designed, but take a look at the GM 5.7, and 6.2/6.5 engines. the injectors and fuel return hoses are right above the exhaust manifolds. SCARY right?
John

Samuel M. Ross · #9 10-26-2006, 10:45 AM

I would only be concerned IF this involved a leak in one of the HP steel lines between the IP and an injector and it does not sound like this is the case.
Regards,

Hatterasguy · #10 10-26-2006, 11:35 AM

Let me guess the car in queston is a 1995-1997 E300D?

Is so don't worry there isn't anything hot over there.

jiggs2006 · #11 10-26-2006, 12:53 PM

You're right, it's a 1995 E 300 D. I appreciate all the responses I have received about potential fire hazard of diesel fuel leak. Looks like the manifold will have to be removed to fix it.

bgkast · #12 10-26-2006, 02:27 PM

Quote:

Originally Posted by benzforlife

yeah, diesel is nothing like gasoline, yes, it is flammable, but it nearly takes an open flame to ignite it, or extremely high heat, which hopefully in ur case isnt happening under ur hood, so i wouldnt worry if its getting fixed!

Diesel can put out a match.

BobK · #13 10-26-2006, 02:36 PM

My GM 6.2 diesel had a seal go bad in hte injection pump. The fuel ran down the valley and right down on the back exhaust manifold runner. Drove like that for forty miles with nothing worse than bad smell and frazzled nerves. After the Carrolton school bus (church bus actually) crash in 1988, the state of Ky mandated all school buses must be diesel fueled. It was a gas engine bus and a bunch of people were killed in the fire.

Hatterasguy · #14 10-26-2006, 08:34 PM

Quote:

Originally Posted by jiggs2006

You're right, it's a 1995 E 300 D. I appreciate all the responses I have received about potential fire hazard of diesel fuel leak. Looks like the manifold will have to be removed to fix it.

When it is fixed replace all the plastic lines on the IP. The ones that are not currantly leaking will start to leak as soon as you touch them. Luckly they are not that pricey, my budy did them on his turbo charged 606 I think it was like $50 for all of them.