CRD

I have seen alot of inquiries in the archives regarding oil temperatures, but could not find an answer to my question(S), so here we go....

I have a 500hp EFI (blue motor) and run 20w-50, change the oil every 15-20 hrs and typically see oil temp. around 145*, sometime 150*. I have been informed that this temp. is too low.


Where is the oil temp. sensor located for this engine?


Is there a t-stat for the oil?


Is the temperature too low?


What should the temperature be?


What can be done to adjust the temperature?



Thank you for any advice!!

Mr Gadgets

Those temps are too low. I would first check the accuracy of your gauge. You should be seeing about 220* after a hard run, monitored after the oil cooler. If you look before the cooler or in the pan then I believe 250 is about max.. I dont know how yours is setup, or monitored. I am sure someone will jump in here to let you know.

Good luck

cstraub69@comcast

You want temp to average around 212 degrees, this boils the water and impurities out of the oil. I'd say your sending unit is bad or the gauge. That is really low. You don't load an engine on the dyno unless you have 180 degrees for fear of hurting something.
220 to 230 okay range
230 to 240 moderate and is okay on a long run, any higher and you should look at a better oiling system.

Chris

CRD

Thanks for the replies so far, any help is appreciated

Active Mike

So where does Mercury want the oil temp sending unit to be located on the block for a HP500?
I'm running two gages in my boat. One sending unit is located on the ledge of the block where the oil pan bolts to and that runs in the 260 degree range. The other sending unit is located at the top of the oil filter base at the back lower part of the block in the center of the base unit and that runs around 225 range when running it hard.
Should the oil pan temp reach that temp (260 degrees)?

BillR

I have 575's and the oil temp stays at 145ish while on plane. Will maybe get to 150 on a run.
While in no-wake zone, temp will get to maybe 190.
Both motors are the same.

Active Mike

ANYONE?

cig1988

Mike, if the hp500 is the same as 454 mag, the sending unit by the filter should be running cooler as it passed through the oil cooler. I'm assuming as the oil returns to the pan it will retain heat from the block. The oil that is directed from the filter will flow into the galleys for the crank. Someone correct me if I'm wrong but this is the impression I have.

Active Mike

Thanks cig1998.
Can anyone add to this?

GLH

I have 600 SC's / 420 B&M blowers on 502's built by Mercury Racing, this is for your information here is what I run;
-I have 140* thermostats
-Water temp is usually 140-150 I have seen 160* after hard runs but momentarily comes right back down after I lay off.
-Cruising around 3000-4250 rpm I am hovering around 180* to190* for oil
-After a hard run for 5 minutes it creeps up to 220 max, I try to get it over 212* every time I go out for the reasons mentioned above.