Hakkas huvitama kuna märkasin kahel põrnikalisel mootoris olevat 20w50 mis pole sinna tegelikult õige õli IMO

Moderaator: ingmar
The VW engine has a bypass valve (a spring and piston) to control the flow of oil through the passages inside the case. Depending on the year some cases have one valve some have two. One purpose of the valves is to control the flow of oil to the cooler when the oil is cold. When the oil is cold it is thick and has enough pressure or force to open the valve and bypass the cooler thus allowing the oil to warm up to operating temp faster.
What often happens is the owner will install a 30mm, or high pressure, pump and run a xW-40 or xW-50 weight oil. So much pressure is generated that the oil bypasses the cooler the majority (or all) the time. The oil never gets cooled and the motor overheats.
What you want is FLOW. The oil must flow through the bearings, cam and lifters and valvetrain for the system to work properly. High oil pressure is not necessesarily indicative of good oil flow. That is why I recommended a xW-30 weight oil. The bottom line is....10psi for every 1000 RPM. Again, this is assuming your motor is in good condition. If, during the summer, you are not getting 35psi, or more, while cruising down the road at 3500 RPM then go to a xW-40 weight oil to bring your pressure up a little. There have been many, many posts on here from guys running 20W-50 oil and experiencing high oil temps. They listen to the advise, switch to a lower viscosity and the motor runs cooler.