502 oil ports
 

My 502 genVI has two oil ports in front of the oil filter boss on the bottom of the block that are I thought in another thread was said to be for a low volume oil cooler to be put in line?Not that it would matter on the cooler but which is in and which is out,and are these ports before or after the stock merc.cooler/remote filter?:I would think they are after.:confused: :cool:

Those holes are for an automotive cooler as used on a truck. The oil coming out of the filter goes to the galley were the plugs are and then back into the engine. If a cooler is used a special adapter is needed to create a pressure differential so oil will flow out one hole and in the other. Without the adapter there is no flow since the pressure is equal at both plugs. About the only thing they can be used for on a boat is for a place to install an oil temp sender to measure the temp of the oil going into the engine after it has been filtered and cooled by the marine cooler. Some people like to know that temperature and others locate a sending unit in the line going to the cooler so they can measure the temp of the hot oil coming out of the engine. Both measurements are OK. It is just whatever you prefer. There are pros and cons for both. There are lots of threads on oil temps.

Good luck!

Macdad thanks.Adapter ok that makes sense, thought that I might try to check oil temp's before cooler and after so that port/ports will work for after temp's on my merc remote/cooler.Also was a thought how much the truck air oil cooler would lower temp's if one was to be put in line along with the stock merc cooler?As you said some people use the ports/port for an temp.sender but when you screw it up into the port will it impead any flow that needs not to be impeaded?

No, you will not impede any flow by putting a sensor in the cooler ports. I would put in the front one though, since that is the end of the galley but, it probably doesn't make a difference.

See ya, Doug

Thanks:)