20VT oil cooler feed & return to cooler info

[20vcqdriver]

I have conflicting info regarding which of the hoses coming out of the filter housing to the oil cooler is the feed pipe. Need to know for sure as needs to be at the bottom of my cooler with the top attached to the return to ensure correct operation. Anyone know 100% which is which. Thanks

[Audi Derek]

The only sure way would be to connect it all up then start the car and keep feeling the pipes and the one that gets hot first is the outlet so thats the one that goes to the top of the cooler..







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[Puglife]

Is there a reason for needing the correct circulation? an oil cooler is a heat dispenser and doesnt affect flow rate through it.... you'd be better with feed to top i'd say. Gravity would assist the circulation slightly (even though its pressure fed).

[Audi Derek]

Jay
Now I wanted to say that but thought that I would be shot down in flames...




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[Puglife]

I live life on the edge Derek

I only ask because for the Group N Skoda Fabia, and the Mk2 escort Asphalt cars I had a lare input in building both had coolers and I made sure the feed was at the top even though it has little bearing.

[20vcqdriver]

Reason for being fed to the bottom is to enure no air lock and ensure all fins receive equal oil as per diagram. Oil filling from the top will take the easiest route so the end fins may not get any oil as it drops through the nearest available fin. Fill from the bottom as on your rads at home and the whole rad will fill from the bottom to the top and pushing all air out of it at the same time.
Difficult to tell on drive as thermostat in housing only kicks in as oil passes 50degrees or more. Even swapped round and measured the temp with a meter at the rad but the hotter part of the rad was always at the top whichever way round I had them, probably because the hottest the oil got on the drive was 35deg?!