YOu are not alone.......
interesting that some are and some are not....
but, Don and King... you are not alone... it happens to more than not...
MOst of the new engines will not get the crud till they get about mid life... why... because they have to develope the carbon on the back side of the piston... ya all them pistons have oil blasted on the back sides of them to help keep them cool and from melting a hole in the middle... ahhh that agressive leaning... does wonders for the heat on the dome of the piston... and without the extra fuel... to help cool it... well.. it compounds the problem...
so why does it happen after that and a oil change... well its thought that the carbon is built up during flight... now while the engine is running along.. the filter gets any of the particles that get washed off as the engine is running... i.e. they are kept in the flow until they hit the filter... and get trapped... now when you put new oil in.. they have detergents that are much more active... as the oil gets older... they wear out first... one reason we say change at 25 hr intervals.. keeps the engine cleaner...inside.. and that is why your oil gets dirty... its the stuff in suspension... its supposed to do that... but, now when you don't fly enough or it sits for a while.. the alu shucks the carbon off the back of the piston while it starts to corrode... and when you start up.. the oil is nice and thick... so the flow is down... and it gives the big rocks of carbon time to settle out in the chambers... well your pick up for the waist gate actuator and controller is right at the bottom of the accessory case .. right where the oil is GOIN into the filter... and slows down... so it settels out and heads for the orffice to do a plug up job..... now on the early skymsters till 72 they used filtered oil from the main feed galley over on the left side of the engine where the oil pressure is taken from... but, they claim that presented problems for the engine... so they moved it back to the accessory case bottom.. and put the fitting thru the plug cap...
So you guys who are flying a lot and on a regular interval... are keeping your engines cleaner insides because the oil is making the trip thru the filter while hot and thin.... but, just because you use 15-50... your not immune from the creeping crud... no actually you are more prone to get it quicker.. as the oil is thiner and it will drop the larger rocks and small children out quicker...than the good old 50 wt oil... but, both have a life limit on the detergents that are in them... and how long they will stay active depends on the amount of dirt, conditions of operation and temp the engine goes thru...
filters are good because they can take a larger amount of the crud before they plug up... and I disagree with cont engine on the fact that it would do damage if it does...after all it does now... and it doesn't do any damage except make the trubo engine a normal.... so I think they are a help... but, they come back with... ya but, its two more hose fittings and something else to leak... Ok... but, if done correctly and maintained it should not present any more problem than the one way valve on the turbo... after all its about the same looking kinda device...
So for you that don't have the problem...YET... your lucky.. but, for those who do...your not alone... we see at least half of the fleet we work on have the problem as age and non use sets in... it get higher in numbers... and yes it does occur right after the oil change because of the new detergents working on the insides...
As to oil and stick levels... you need to go back to the Cont engine site and look up the SID on the dip sitcks.. and how the manufacture wants you to check for proper reading levels... yes they are not all correct.. as their are different lengths of indicator tapes... the part that goes in the engine... to show what the level is... and they want you to check... sometimes the tubing slips on the hose part and will make it longer or shorter which in turn makes it read more full or less...
Hope this helps.. ya understand why the carbon is a problem in the 360 engine... GMAs...
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