Checking Engine Oil Level - Hot or Cold Engine

[Reardon]

Hi Fellow Boaters

This is probably the easy question for the day. I have a Carver 404 (twin Mercruiser 7.4L engines) and am curious if you check your oil level with the engine cold or warm/hot. When I google it, several recommendations are cold, but wanted to get some "real world" opinions.

Thanks
Rich

[waybomb]

It doesn't matter, but I check them before I start my engines every time I go out. Also makes me open the hatch, check the bilge, smell for stuff, etc.

[mjk1040]

Rich; Got to go with cold. The stick is marked, I do believe, for cold oil. And we all know that oil expands some as it get hot.
And I agree with Fred, check them before going out. Mike

[tomschauer]

I also always check mine cold, before leaving the dock. Doesn't do much good for the engines to find out they were out of oil after you ran them for a couple hours.

[Viper]

I check cold but here is something to keep in mind; when checking cold, I like my level to be between the half way and top of the mark (not over), and while oil expands when it's hot, I expect the level to be lower than the cold mark as some oil would still be draining into the pan for a while from the block and lines to the remote filter in some applications.

When doing an oil change, it's best to run the engine to temp first. When you refill, it's typical to start and run the engine for a few seconds to fill the filter, then recheck level and top up as necessary. If you top up right away to the level mentioned above without allowing time for draining, you will over fill the engine. Pretty common mistake. If you're going to top up right away after engine shut down, allow for the drain-back.