vwlover77 wrote:By the way, what point is there in having an oil filter if not to keep the oil cooler and bearings from being contaminated?
Does some oil bypass the filter on its way out of the oil pump?
Although the contamination issue is actually far more serious with a Type 1 engine, I bring it up as but one of your list of concerns to address with this engine builder to help you get back up and running.
The scenario with a Type 4 engine does include damaging the oil pump which is upstream of the oil filter. Only in rare instances does the oil filter get bypassed, when very cold thick oil hits the media or when it is seriously clogged.
Now consider the path of the oil transmitting your wiped bearing material and shards of crankshaft journal. It gets flung out of the bearing and washes the crank/camshaft gears with metal shards/flakes that then add camshaft gear magnesium to the mix. This oil can get flung into the crankcase splash and deposited on lobes and lifters. Eventually it does get down to the sump where some of it will separate from the oil stream. When the damaged bearing oil is picked up and sent to the pump, it is loaded with particulates that give the oil a grey color. The bearing babbit is not much of a problem, the magnesium particles from the exposed cam gear are. The filter will remove the larger particles. Though the remaining particles will be smaller than the oil clearances, but they are not necessarily smaller than the oil film which is the layer of oil that survives the load placed on it. This increases abrasiveness over time, not an abrasiveness that you can feel with your fingers but an abrasiveness that can disturb the smooth finishes between lobes and lifters and gear teeth and much more slowly the main and connecting rod bearings. Subsequent oil changes will, of course, diminish the effects. But do not ever rely on the oil filter to protect you from metallurgical failures in the engine. You will do better to assume contamination has occurred. As for the cooler, Tom Wilson and others say throw it away if you have ever dropped a valve or thrown a rod, I don't quite agree with that, a thorough cleaning and a couple of trips through a parts washer followed by another thorough cleaning should take care of it, but take it seriously. You have metal failure and plenty of nooks and crannies in your engine. And this was all totally unnecessary.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles