So normally these threads go my oil temp is too high...mine is the opposite...my oil temp is not coming up like I believe it should

460 with dart heads 8-71 blower

Idling around the gauge which starts at 140 does not move at all...after running pretty hard for a few mins the needle moves up to right at 140

Sending unit is located above the stock oil filter pad in the normal hole right there...I have the stock merc oil filter relocator and stock oil cooler that came on the motor...it started life as a 525sc merc motor

I'm thinking maybe the thermostat in the relocator housing is stuck open but not sure if that actually happens or not or if I should be looking somewhere else??

thanks

Yea that's a good idea...may just replace it if I pull it...at least have one on hand incase it is bad...sh!tty part is I have to either pull the port tailpipe or unbolt the housing to get to the thermostat lol

I've been running it with the hatch off as I plan to get a new interior made this winter....that being said it is 140 not 240 lol

I did swap the water temp and oil temp sending units to make sure that wasn't the issue and both gauges with either sending unit read the exact same so I know everything is good just not sure if its an over cooling issue or if the thermostat could be stuck or what?? Not sure if these have been known to stick or if my problem is elsewhere...that is a good idea to pull it and check it so I'll probably start there and see what I have I suppose...

If I recall the oil temp gauges start at 140°F. So it could be cold and read just below the 140°F mark. That location I believe is cooled oil returning from cooler. So it appears the cooler is doing its job. If you want to know how hot you oil is getting you need to change the sender location to oil that is not cooled. I personally like to know the temp of the oil that is going to my main and rod bearings not the temperature of the pan oil.

I agree with that but shouldn't it still be heating up to over the 140 mark? The oil filter housing to my knowledge has the internal thermostat that should bypass the cooler until the oil is up to temp...that being said I was expecting to see it come up to 200 or whatever the thermostat temp rating is then drop when it opens...maybe I'm wrong on that but I assumed it would work just like a water thermostat in that I should be to see it drop when the thermostat opens??

My oil temp on my cooled oil barely ever goes over 145°F. If you touch the uncooled delivery hose it's warmer. I also run 168°F oil thermostats.
Get one of these and shoot the pan. Handy and you'll use it more than you think.
https://www.harborfreight.com/121-in..._q=thermometer

Oh yea I have a couple of those lol...so knowing where my sender is you think that's the "cooled oil" and maybe everything is fine? Just thought it had to heat up to burn off condensation and honestly I was expecting it to go the other way and have to add a bigger cooler...is the merc cooler really that efficient?

Thanks for the replies!!

Shoot the cooler itself. The oil runs through the shell so If it is cold and the filter is hot it means the oil is bypassing the cooler.
Shoot the pan - if the pan is hot and both the cooler & filter are cold it means the oil is bypassing entirely. Won't be the first time someone left the bypass valve out of the oil adapter or the block or used the wrong valve (too low pressure).

After running hard 200-250 plus in the pan is expected