What is this engine fluid spray?

[911kevin]

I have been watching a number of BAT auctions and have taken note of a number of 911 engine compartments having this fluid spray line on the engine lid. Does anyone know the general cause? Thanks.

[911kevin]

Neglected to add images.

[jlex]

Bad seal on the air conditioning compressor. Oil from the AC being flung out onto the lid. Seal is replaceable.

[DanielDudley]

Yep. Oil on seals creeps up the pulley and gets flung in a nice straight pattern.

[911kevin]

Ahhh. Makes sense. Thanks.

[otto_kretschmer]

I had the same oil pattern on my old suburban

should have kept that truck and kept fixing it

[smadsen]

Or someone sprayed too much "stick-um" on the fan belt. If it squeal's, just easier to just move a shim.

[Apollo13]

Is the leaking compressor seal an items that can be replaced without losing the refrigerant charge, or does it mean a complete rebuild or replacement? My a/c is working wonderfully except for it does seem to have this spray coming from the a/c compressor which happens with the a/c on or off (wipe it away after each drive). The spray residue line on the lid is directly over the belt/clutch of a/c unit and the fluid seems very much like motor oil (have been hoping it is not that). The belts are dry and have never been dressed. It has been bothering me for a while.

[jlex]

Good question. Someone who does AC work will have to chime in. I've always worried that it's compressor oil that's being flung out which will eventually cause a low oil situation and harm the compressor. I have recharged with R12 compressor oil to make sure the oil level doesn't get too low.

[dannobee]

Yes, the front seal on the compressor is leaking. Refrigerant carries oil that lubricates the system. When the refrigerant escapes, some oil does too. It's that oil that gets flung out during operation.


Seal replacement requires evacuating and recharging the refrigerant. Discharge/remove the refrigerant, replace the seal, vacuum down the system, then recharge.