New engine bearing wear?
New engine bearing wear?
(OP)
On a new engine is it true to see some small bearing debris in the oil filter?
From my understanding when the bearings are newly installed they are not perfectly round as the journal they are riding on is?
I have seen this on 2 new engines and the wear found is no longer found after about 1000 miles and 4 oil changes.
Both engines were pre lubed with oil and clearances verified.
Just looking for some truth to this.
From my understanding when the bearings are newly installed they are not perfectly round as the journal they are riding on is?
I have seen this on 2 new engines and the wear found is no longer found after about 1000 miles and 4 oil changes.
Both engines were pre lubed with oil and clearances verified.
Just looking for some truth to this.





RE: New engine bearing wear?
Mike Halloran
Pembroke Pines, FL, USA
RE: New engine bearing wear?
On a recip piston engine with journal bearings, there will be lots of "bearing" debris generated and collected in the lube system filter during the first few minutes of operation. But this "bearing debris" usually consists of soft tin and babbit overlay materials and is fairly harmless.
The filtration level selected for most oil filters is set such that any debris particles passing through the filter are still small enough to pass through the journal bearing HD oil film without causing abrasion to the journal or bearing surfaces. For a typical crank bearing, this would be about 50 micro-inch or less.
So to answer your question, yes it is true.
Regards,
Terry
RE: New engine bearing wear?
RE: New engine bearing wear?
RE: New engine bearing wear?
It's not a matter of disassembling an engine and chewing on the rod and main bearings ... it's a matter of the engine being shredded indiscriminately at the end of its life in the junkyard, and the lead getting mixed in with absolutely everything. You can magnetically separate the bulk of the iron, but lead alloyed with other stuff is hard to get out, and it ends up contaminating everything and partially getting airborne in the process (lead melts and vaporizes well below the temperature at which aluminum melts, for example). Lead in the journal bearings also gets into used motor oil during normal engine operation, and contaminates that, also.
RE: New engine bearing wear?
The engine lasted about 2 weeks when the bottom end and cam bearings were wiped. Another Ford dealer did the disassembly work and asked who did the initial work. They replaced the complete engine when they found the fiber debris from the rollock pad embedded in the inserts and the filter.
Franz
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RE: New engine bearing wear?
RE: New engine bearing wear?
tsifreak, How much bearing debris is being seen in your filter? On the engine production lines I'm familiar with, each engine is "hot tested" before being shipped. During the hot test, the engine is run and a special filter is used to catch debris for examination. If much debris is found, the engine is sent on a trip through the service area to figure out what's wrong. Either way, the oil is removed and replaced, and a brand new filter is installed. There's not much left after hot test for the customer to find.
RE: New engine bearing wear?
Brian.
RE: New engine bearing wear?
RE: New engine bearing wear?
RE: New engine bearing wear?
The crank is a virgin crank uncut. Bearing clearances were set at .0028. Oil to be used will be Brad Penn 15/40.
Engine is a 4 cylinder mitsubishi 4g63 turbo motor that will see 600 HP.
RE: New engine bearing wear?
RE: New engine bearing wear?
RE: New engine bearing wear?
RE: New engine bearing wear?
RE: New engine bearing wear?
Norm
RE: New engine bearing wear?
RE: New engine bearing wear?
Norm
RE: New engine bearing wear?
RE: New engine bearing wear?
If particles observed are bigger than the filter that means there is problem in the engine. In that case a metallographic inspection to identify the material composition should be made in order to find where debris is coming. At least this is the normal procedure followed for airplane engines.