Curious about the zinc in break in oils......

[bandit67]

Zinc is an element that we use in our motor oils to ensure minimum wear during engine break in. We are told this is essential in avoiding cam/lifter failures at start up. We buy infused zinc motor oil, zinc oil additives , and , I assume the cam lube paste we apply directly to the lobes also contains high amounts of zinc. My question is , is the zinc in these forms small enough to pass thru an oil filter or is it getting pulled out as the oil flows thru the filter. I understand from my old Chevy days that only 12% of oil flow on stock engines passes thru the filter while running. Would that be a fair assumption on stock Mopar engines in general as well. Just wondering if we are poking it in there and the filter is pulling it out...thanks....

 

[j-c-c-62]

Zinc is an element that we use in our motor oils to ensure minimum wear during engine break in. We are told this is essential in avoiding cam/lifter failures at start up. We buy infused zinc motor oil, zinc oil additives , and , I assume the cam lube paste we apply directly to the lobes also contains high amounts of zinc. My question is , is the zinc in these forms small enough to pass thru an oil filter or is it getting pulled out as the oil flows thru the filter. I understand from my old Chevy days that only 12% of oil flow on stock engines passes thru the filter while running. Would that be a fair assumption on stock Mopar engines in general as well. Just wondering if we are poking it in there and the filter is pulling it out...thanks....

Well, that is 100% more than when it's not running,
Seriously, where did you hear that and clarify/explain how exactly?
If the premise is true that zinc is filtered out 88% every time it passes thru the filter, it would be very easy to bench test and prove I suspect, and I highly doubt it is.

 

[68-500]

I have also heard only a portion of oil circulating gets filtered. But I haven’t found anything to substantiate that claim. I believe the zinc is smaller than your average filter catches.

 

[Lefty71]

When the filter clogs, 100% of the everything passes thru the engines oiling passages.

 

[j-c-c-62]

In most cases, but when have you last heard of a filter clogging 100%?

 

[Krooser]

In most cases, but when have you last heard of a filter clogging 100%?

I have seen it person on an engine with a leaky head gasket.

Many filters filter about 25 microns ... the bypass filters I used on my diesel engines were 5 microns. 50k on the oil and it was still clear.

Every factory filter I know of is a full flow... the filter is in the main oil gallery and every drop gets filtered. Bypass filters were used 70 years ago on engines without primary oil filters... flathead fords, mopar flat sixes, chevy stovebolt 6's, etc.