Letting Oil Drain Out for a week

[odonnellryan]

Hey all,

Just bought this boat and going to do the first oil change.

I'll have to see if I can access the oil plug (I think I can but I have to verify) but if so, is it OK to let the oil drain into a pan for a few days to a week?

Obviously if plug is not accessible I'll have to pump it out.

I figure it'd really let everything come out, but maybe not a good idea b/c of moisture etc getting up into the engine somehow? Or maybe that is not significant?

[sailormed]

Moisture not significant, just be sure you do not get critters in there.

[DougR]

Let it drain until it stops dripping. Anything more is unnecessary.

DougR

[Stu Jackson]

Most/many engines are installed on an angle. Unless the oil drain hole is at the lowest point (and many aren't) it won't matter how long the plug is out. Not like a car.

[hellosailor]

ryan-
Unless you are planning to do a kerosene flush of the entire engine, to REALLY get the old oil out, just let it drain out. When the drain turns into a dribble, close it up and pour in the new oil. The ounce or two of old oil that remains will be so diluted that it makes no real difference. Better to do the job ALL AT ONCE and COMPLETE and have it done with.
And, typically to change the oil filter first--to make sure the old one will come off, and the new one is the right filter and it does go on properly.

[shakey doug]

Priming can become an issue if any oil pump wear is present.

[thinwater]

Honestly, the more effective method is to do the first oil change at a really short time interval, perhaps just 10 hours. You don't need to change the filter again, which makes an oil change with a pump really easy. By far the easiest, safest way to clean an engine.

[Allied39]

Originally Posted by thinwater

Honestly, the more effective method is to do the first oil change at a really short time interval, perhaps just 10 hours. You don't need to change the filter again, which makes an oil change with a pump really easy. By far the easiest, safest way to clean an engine.

Yup, good advice.
It does not even have to be 10 hrs. Two or three oil changes in 20 odd hrs of run time will leave your engine clean.
Change your oil every 50hrs after that will keep it clean.
Some will say 50hrs is to little, but consider the cost of an engine rebuild or replacement and $25 (yes it varies but approx) every 50 hrs is a no brainer in my opinion.
Lastly, you need to have a good way to change your oil. Whatever the system, set it up now, cause you should be using it every 50 hrs.

[odonnellryan]

Sounds good. Seems like I will go for changing the oil 2-3 times over 1-2 days and see what I end up with.

Thanks guys!

I've seen a lot of neat systems for quick oil changes. I'll have to see what works well for my engine. Good idea to take care of that problem now for the first time.

[Wotname]

^^ Curious, what engine do you have?

[Lepke]

Something you might think about on your next oil change, you can buy a locking valve that fits the oil drain. Then attach a hose long enough to drain in a convenient place. You can leave the hose in place, maybe plug with a bolt and hose clamp for added safety. Then it's less of a struggle. If your bilge is deep enough you can drain into jug big enough to hold all the oil.

[odonnellryan]

I have a Yanmar 3QM30. I believe it has a drain plug for oil near the transmission. I have a good amount of room under the engine actually where I feel like if I am right about the plug I can reach it for sure - but maybe not.

[Wotname]

Originally Posted by odonnellryan

I have a Yanmar 3QM30. I believe it has a drain plug for oil near the transmission. I have a good amount of room under the engine actually where I feel like if I am right about the plug I can reach it for sure - but maybe not.

The 2QM20 has two sump drain plugs; one on the front LHS and one on the rear RHS (under the engine dipstick).
They are 22mm (though 7/8" is pretty close).

There is a third plug that looks like a drain plug on the centre of the front of lower section of the block. It is a little higher than the other two plugs and while it will drain most of the sump, it won't drain as much as the other plugs. It's purpose (I believe) is simply a manufacturing plug for the machining for the oil pickup tube which directly screwed into the block on the inside. This one is 19mm (again 3/4" will work).

I suspect the 3QM30 will have the same arrangement.

[captmikem]

couple of thoughts, if you can get to the drain plug, Aircraft have a Curtis drain which is a quick drain valve:
https://www.aircraftspruce.com/catal...clickkey=16663

or there are handy oil suction kits available that make an oil change easy and clean
https://www.westmarine.com/buy/west-...14?recordNum=5

if you get your engine warm, drain the oil, dump in a gallon of diesel, run it for half a minute or so, then drain it you will have a clean engine. You can do it cold as well, but it does not get it as clean. I do this about every 5th oil change.

M

[Midnight Son]

odonnellryan
The most common quick drains.
https://ezoildrainvalve.com/index.html
https://www.fumotooildrainvalve.com/
There are others, as well.
Cheers, and Seasons Greetings.