7850 filter ID

The filter on the frame rail is the by-pass or secondary oil filter. It replaced the luber-finer canister that was located in the open behind the engine. Although a very good design, they were sometimes problematic and prone to leaks if not assembled properly. Allis then installed and updated units to this spin -on type and actually the filter is not a by-pass type, but a full-flow filter, 3306 CAT if I'm remembering correctly. It serves the purpose well though and oil flow is restricted by the orfice coming off the oil cooler. It was meant to mounted above the starter. The small filter above it is the coolant conditioner filter. ,HTH, Mike

1791 NAPA, lube filter, Your welcome and good luck!

I was told from the guy that I purchased it from that he bought it 2 years ago. It ran and drove off the trailer to where it currently sits. No idea where it originally came from or how long it had been there, but it appears to have been a number of years.

I too would say an engine bypass filter. I would also add it was put in a very dangerous place. Dirt and mud are going to be constantly hitting it as well as the oil lines. The correct place for that is up in between the starter and that water filter.

The first bypass filters were up behind the engine, and under an orange hood that was held down with two springs one on each side. They had a seal that would go bad and dump all the oil out on the ground under pressure. The spin on bypass was a much needed changeover.

Edited by Unit3 - 10 Mar 2024 at 11:26pm