PeachParts Mercedes-Benz Forum - View Single Post - Oil cooler plumbing on alloy block m117/116

rwd4evr · #2 04-03-2025, 06:26 PM

The oil cooler will do essentially nothing without the bypass valve. That's what Ive been doing for 7 years in my iron 4.5 and never realized it until a couple years ago when I went down this rabbit hole. There's nothing in the block main oil passage when you have no oil cooler. You add an oil cooler , great. But the path of least resistance hasn't changed. The bypass valve plugs the main oil passage, sends it to the cooler loop until the cooler loop is a restriction, and it bypasses back to the main oil passage. Mine barely gets warm while beating the snot out of my car all day. Some oil might meander through there but it's got no good reason to. Thermal siphoning? You could hook an auxiliary pump to it to circulate but I imagine a pump that will be trusted to not leak under oil pressure would be expensive. You really need the bypass valve.

Sent from my SM-G991U using Tapatalk