Black goo

[dresserman]

Today while repairing a windshield fluid tank leak I did a general under the hood inspection. To my supprise I noticed a small amount of a BLACK GOO like substance coming from the outside edge of one of my Injectors. This BLACK GOO like was approx. 1/4 inch wide and about 1/2 inch long on one side only of the injector. It is hard to the touch and looks like something melted and seeped out of that area. NOW, my question is what is it and why is it there?

[sixto]

That black goo probably leaked from the joint between the crossover pipe and intake manifold onto the #2 injector. If so it's blow-by oil courtesy of PCV mixed with exhaust soot courtesy of EGR. Fit a new gasket and you should be fine.

Sixto
93 300SD

[dresserman]

The black goo did not drip onto the injector. It has emerged between number four cylinder injector the sleeve and the injector bore. It came out of that area so there has to be a leak of some type, looks like tar. Reminds me of a volcano eruption. You would think there would be a performance issue here but the car runs great. Do you think there is a fuel leak there causing the black tar like substance? Maybe an injector leaking but only at one point? Maybe a small leak at the injector to cylinder head seal ring???
Strange.

[sixto]

Originally Posted by dresserman

Do you think there is a fuel leak there causing the black tar like substance? Maybe an injector leaking but only at one point?

Nothing in the injector but fuel. This isn't a Powerstroke

Originally Posted by dresserman

Maybe a small leak at the injector to cylinder head seal ring???

You can put some water in the area and see if there are bubbles when the engine's running.

Sixto
93 300SD

[dresserman]

OK, today I took my bottle of soap n water out, got my flashlight, opened the hood and started the engine. Then proceeded to spray that mixture all around the fuel lines and injector area. To my supprise there are air bubbles coming out of the BLACK GOO area. The bubbles are a steady flow at idle. It looks like the air is coming from between the injector dirt sleeve and the cylinder head??? A bit hard to tell. So I then proceeded to take a 30 mile ride and get the whole package good and warm. Then before shutting down the engine I again sprayed the above area thinking that when heated it may not leak air as bad. Wrong, it seems to leak the same amount. SO, if this is a compression leak that would make the air burnt/fuel/oil become a BLACK GOO, Right????
SO, looks to me like I may have a cracked cylinder head??? Why would it crack at this location. OR maybe a cracked injector body???? All I know at this writing is there is an air leak there. If I have time tomorrow I want to see if that air has anything in it that may burn.... Then I will have to hunt down an injector and seal. Also pull a compression check on that number four cylinder also.
Fun, WOW.
It is hard for me to understand how this car can run so well, get great fuel milage, and have a compression or whatever air leak in one cylinder. It probably isn't the only diesel with constant compression relief.
OH well, I hope it is not a cylinder head crack. I don't have the time to play with this car. It may just have to go down the road.

[sixto]

Is it leaking between the injector and the lockring or between the lockring and the head?

I doubt the head is cracked. In any event the early 603 heads that develop cracks do not develop cracks in this area.

You might install a new heat shield to see if that fixes the leak. FastLane has heat shields for $2.50 each. Injector torque is 70Nm.

Sixto
93 300SD

[dresserman]

Not sure exactly where the leak is. Will do some closer evaluation this weekend.
Will order and injector, w/seal and heat shield then. I looked on fast lane and could not find the heat shield listed for my 602.962 diesel engine, where are they listed??
Thanks
Den

[2.5Turbo]

I would assume it would be the same for all 60x engines. At least the late 80's-early 90's 602's and 603's. But I wouldn't count on it, just pure speculation.