Oil draining vs. extracting

[matt 57]

I've been changing oil in my cars and trucks for over 30 years now and never thought of getting one of those oil extractors. I've seen quite a few oil pans removed from old car engines and always thought that draining is the best way to get most of the dirt out.
Now I got my first boat and looks like I have to get one of those oil extractors. This would be the last thing I want to save on.
It would be nice if you folks, experienced with boat motors share your thoughts on this.
And also what about flushing the oil system?
Any recomendation on a good extracting device will be greatly appreciated. Thanks.

 

[HT32BSX115]

Re: Oil draining vs. extracting

Howdy,

There's probably no other easier way to get the oil out than using a vacuum type extractor.

Most of them use a rigid plastic tube that goes in the metal dipstick tube to "suck" out the oil. Since it's a fairly small diameter tube the oil needs to be warm or it's a slower process.

Some dipstick tubes are connected to the drain hole in the pan so you pretty much get all the oil you would get by draining it using gravity.

Others use the actual dipstick hole and you're limited to getting the oil that the plastic tube is submerged in. If it's not all the way in then you might not get it all etc...


Another way to do it is to use a drain hose that connects directly to the drain port. Mercruiser does this on new boats. You can then "snake" the hose out the transom drain hole and let the oil out via gravity. (you can also use a vacuum extractor to suck the oil out of that tube too.....that's how I do it because my after market hose will not fit thru the transom drain.)

Either way works fine. It's not a big deal if you do not get all the oil.

And also what about flushing the oil system?

I would NEVER DO THAT ......Aside from being a waste of money, you run the risk of breaking loose a piece of debris that could plug an oil passage (after the filter) that could starve a bearing.....(can you say "spun bearing"?)

I'm using the following one to do my oil (I use it for other things like my automatic trans too!)

http://www.moellermarine.com/aftermarket/maintenance/fluid_extractors/

I think mine is the 4 liter model!



Cheers,

Rick

 

[matt 57]

Re: Oil draining vs. extracting

Thanks.
You say "Some dipstick tubes are connected to the drain hole in the pan".
Just wonder wich way is it in my engine, I got '77 Merc 888.

 

[HT32BSX115]

Re: Oil draining vs. extracting

You say "Some dipstick tubes are connected to the drain hole in the pan".

I cannot say with yours. If you don't have a Merc service manual and you don't want to download one (look up above in the main forum) Then just get a flashlight and a mirror and have a look. You should be able to tell by looking.


My 454 Mercruiser uses the original dipstick location used in the automotive engine application. My previous 460 King Kobra had the dipstick in a tube connected to a hole in the pan that looked to be the original drain hole......A lot of engines are that way.

 

[myoldboat2]

Re: Oil draining vs. extracting

I used a dipstick tube pump for a few years and thought it was a pain. Seemed like I always dripped some so I had to put down plastic anyway. And I wasn't getting everything out of the bottom of the pan. This year I drained it into the bilge and then cleaned it out. Next year I'm going to try the recommendation on this forum to slide doubled-up garbage bags down there and drain into them. Should be able to loosen the filter and drop it in the bag, too. Then work it out one side and snip a corner over a funnel into the drain oil jug.

 

[matt 57]

Re: Oil draining vs. extracting

I have the manual downloaded and keep reading it for a few days now.
I'm a one week old boat owner and there are so many questions.
Hopefully I'll learn all this boating stuff soon.
Thanks.

 

[ziggy]

Re: Oil draining vs. extracting

i'll second HT's method of engine oil removal. i've got one of them vac. oil extractors too. it's a shade slow, but it's too clean and easy to do + on 'my' boat, the oil pan drain plug don't come out w/o raising the ft. of the engine. so the oil extractor is a no brainier in my case.
i know i get all the oil out of it because the tube on the extractor runs all the way down the dip stick tube and i can hit bottom (of the oil pan) with the extractor tube. when empty, ya can here the pan go ting ting when the extractor tube hits bottom.
i like mine a lot... makes taking the oil to be recycled easy too.... imho..