Hi all,

I have just pulled the injectors on this e99 and the #1 injector has rust from about a 1/4" from the copper washer to the bottom o-ring. It is lightly pitted...no doubt rust. However, there is no fuel or oil in the degas bottle. The volume of the degas bottle has not increased or decreased. There is no oil in the degas bottle either. There is a slight discoloration on the side of the cup that runs parallel to the to the axis of the piston and injector. I do not have the ability to pressure test. Is this a cracked cup? How can there be rust on the injector yet no fuel in the degas and no volume increase or decrease in coolant?

Thank you in advance for any help....

 

I've seen a cracked cup leak with no pressure at all. Just tiny little drops ooze out the crack and run down into the cylinder once the injector is removed.

Is there a reason you can't pressure test it? If nothing else hook a garden hose up to a heater hose to put some pressure in the system. One of those plastic T fittings that comes in a flush kit that you can screw a hose onto would be ideal, but any homemade contraption that got some water pressure into the system would work as well.

 

The copper washer on the injector will keep things out of the cylinder if the injector is down tight. This would hide a damaged cup for a long time, if you have one.

 

F350-6 Yes. When I was working on it yesterday I had removed all of the hoses which were taken to a parts store to ensure that all replacements were compatible. So, now that I have them back I could do the test. However, I ordered the tool set from Riffraff and had it overnighted late yesterday. I decided that while I am in this deep I may as well err on the safe side and replace them all due to the fact that upon further close inspection there may be one more w the beginning of rust.

Tugly Thank you for the explanation. I read about all of this for about an hour and looked at the various pictures and was not able to arrive at this conclusiin on my own. Now it makes perfect sense.

Thank you both for your replies!