I want to install an oil temp gauge on my new 502, its a brand new casting and has two threaded holes above oil filter boss on block, so i was thinking of using the 3/8 one...the other has my low oil switch on it. I know the pan is the best location, but without pulling motor out whats the best option. I even thought of taking the remote filter boss and drilling and taping a hole....

I lasered my pan this weekend and its getting 180-190 on short 4000rpm runs with 4800 blast for a fw seconds...same with filter about same temp.

anyone?

there is nothing wrong with those temps other than being a little cool.

i suggest the same test after using the boat in a manner that you normally would and seing what the temps are and go from there.

as for a sender, assuming you don't want to put a fitting in the pan, you could always drill and tap the adapter or make a fitting that goes in the oil inlet line before the adapter... either one is easy and doesn't involve taking the motor apart. i have seen people make threaded adapters for the oil drain plug hole and put it in there altho that makes getting the oil out a bit of a pain...

When you say oil inlet, can i drill and tap a hole up on the filter boss...that would be the easist for me. My drain plug has a drain hose on it so thats out. I do have that extra hole above my filter boss on the block that goes into the oil galley....those temps would be what i should be reading.....that right out of pan right?

Just use the NPT port on the remote oil filter. I know a lot of people using this. Professionals correct me if I'm wrong but oil goes from the pickup - out the side of the block - to your filter/cooler or cooler/filter depending on your setup - back to the block - through the crank, rod and mains - through your cam - though your push rods - to your rockers - then drain back down to your pan.

So if you are taking the temp from the filter port you are measuring the oil from the pan with the added shear heat you get from the gears in the pump, and still before it lubricates your important parts. But you need to decide wether you want it before or after the cooler or both.

I dont have a NPT on the remote filter pad, i would have to drill and tap one...the only one i have is on the block right about where the oil filter would mount if you dont have a remote filter/ cooler system. I was think sort of like you...in that the oil will come out of pan through pump into the oil galley above filter boss then through everything else.

Sorry, Yes I would use the one on the side of the block. Make sure the sender does not stick to far into the oil stream and impede flow.