Oil filters & engine health

[Dadpole]

Tonight I was engaging in the messy task of ripping apart my oil filter and wondered if the subject hat been mentioned here before. I always pull apart and examine my oil filter after changes to get a general indication of wear and to check for unusual objects.
If you check the photo you will see a suspicious sliver of metal. This is 4 mm long and has me wondering just where it is from. A piece of tooth from the gearbox perhaps - the engine pulldown next winter will provide the answer (I hope).
Another reason to examine the filter is to check for something specific. In the case of this engine (old air cooled 1100 Suzuki) any gold or brassy coloured metal means the washers next to the crankshaft bearings are badly worn. This is not good news, as the next indication is often a loud bang at high engine speeds as a con-rod makes a bid for freedom.

[marty]

we do oil filter inspections all the time on high stress turbine engines that run for 6 to 8 hours a day. there are often (almost always) small pieces of metal in them - a flake off a gearbox tooth is not going to grenade the engine. you should be concerned about bronze (from bearings) or many pieces of gearbox teeth, but a single flake shouldn't be too much cause for worry.

[Dadpole]

True, a single flake is not a problem, and being a roller bearing bottom end means any bronze metal has to be from the washers, The pull-down next winter is coming regardless. The lump will have done 100,000 km by then, and there are few modifications to be done.

[Kickaha]

we do oil filter inspections all the time on high stress turbine engines that run for 6 to 8 hours a day. there are often (almost always) small pieces of metal in them - a flake off a gearbox tooth is not going to grenade the engine. you should be concerned about bronze (from bearings) or many pieces of gearbox teeth, but a single flake shouldn't be too much cause for worry.

do you run a oil analysis program as well?

[marty]

only if there is what we deem to be excessive flakes or material present. the oil system loses about a quart a day through the oil/air separator, so it is effectively replenished every 10 days or so. filters are done every 200 engine hours, or if excessive debris found, a full flush and check after 10, then 10, then 50 hours

when i say all the time - we've got 32 engines, so it just seems like it's all the time......