Engine Oil Drain

[egldvrbags]

1995 4.3LX Merc Alpha 1

As an alternative to using a pump through the dipstick port, has anyone had success/issues w/ using an engine oil drain system that uses a hose through the bilge drain.

Here's one:
http://overtons.com/modperl/product...Oil-Changers-/-Filters&r=view&i=26163&aID=24A

Thanks in advance!

Dave

 

[njlarry]

Re: Engine Oil Drain

I'd like to know that too. Some Mercs came with oil drain hoses.
I have good results with just a drill powered pump and old garden
hose screwed to the dip stick. Does a drain hose setup get
more oil out faster or just add another maintance item?

 

[salty87]

Re: Engine Oil Drain

i've had one of those in my spare parts pile for a few years. not enough room between my oil pan and hull to install. i have the engine out now and if the hose will fit, i'm putting it on before the engine goes back in.

draining from the bottom of the pan will get more junk out than trying to lift it up the dipstick, get more oil too.

 

[wire2]

Re: Engine Oil Drain

draining from the bottom of the pan will get more junk out than trying to lift it up the dipstick, get more oil too.

Keep in mind, the dipstick on most marine engines goes to the drain plug so it's essentially the same thing.

The drill/pump will work, just takes a while.
I use a small cylinder (old 25 lb Freon cyl), pull a high vacuum with the inlet of a compressor, then connect with a clear hose to the dipstick tube. It pulls 5 L out in ~3 min.

 

[Don S]

Re: Engine Oil Drain

You also don't have to put a tube in the dipstick tube on most Merc engines of the mid 80's forward. If you look at the end of the tube it has threads for a hose that you can attach to a pump.
Make sure you warm the engine up before trying to drain the oil.

 

[BAYLINER185]

Re: Engine Oil Drain

My boat came stock with the drain hose that you pull through the bildge drain. Im planning on usign that.

My dealer said however it takes a really long time to drain oil usign that and I cant imagine why unless he wants me to bring the boat in every time for them to do it and thats not going to happen.

I was also told you can use the drill pump on the drain hose and really pull some crap out of the oil pan! I want to try that as that sounds like a good idea and a good way to get all kinds of sludge out!

They also say to loosen the oil filter when you use any method of oil changing as it will allow air in and th eoil to flow out faster. Either if you use the drain hose or dip stick pumps. I remember on my old boat I did the drill pump down the dip stick trick and it took foever to pull all the oil out. But Im thinking if I loosened the filter it may not have been so long to remove all the oil!

 

[45Auto]

Re: Engine Oil Drain

My boat has the drain tube through the bilge set up. It sure doesn't drain anywhere near as fast as a car!! I warmed the boat up on muffs for about 15 minutes, temp gauge showed a steady 160, right where it runs normally. Went to drain the oil and it was coming out real slow, still cool. Figured maybe the motor wasn't really getting hot enough with no load on it. Plugged it back up and took the tools and drain pan with me next time I took it out. After running all day I pulled the drain tube on the ramp and got the exact same thing - little stream of cool oil! So I took it home and let it drain for several hours. Must have got it all out, specs say 10 quarts and thats what it took to fill it back up. It does have a closed cooling system on it, maybe that's helping keep the oil cool.

 

[wire2]

Re: Engine Oil Drain

They also say to loosen the oil filter when you use any method of oil changing as it will allow air in and th eoil to flow out faster. Either if you use the drain hose or dip stick pumps. I remember on my old boat I did the drill pump down the dip stick trick and it took foever to pull all the oil out. But Im thinking if I loosened the filter it may not have been so long to remove all the oil!

The crankcase is vented through the heads and rocker cover breathers. Loosening the oil filter won't affect flow rate, it's strictly gravity and restriction.

My boat has the drain tube through the bilge set up. ..... I warmed the boat up on muffs for about 15 minutes, temp gauge showed a steady 160, right where it runs normally. Went to drain the oil and it was coming out real slow, still cool. ....... It does have a closed cooling system on it, maybe that's helping keep the oil cool.

There's probably a bit of water in your bilge? As the oil comes out, it's being cooled by the hose laying in the water. A built-in heat exchanger.

 

[45Auto]

Re: Engine Oil Drain

Bilge is perfectly dry. The rubber hose is very thick with a relatively small hole in it. Maybe it's long enough that the oil has a chance to cool off while running through it. Or maybe the hose has some sludge in it. But the boat only has 100 hours on it and is on it's 4th oil change, the oil looks real good. I'm using the Merc 25/40 factory stuff, maybe it's just thick. Not sure why it's slow, I had always heard it took several hours to do a complete drain. Didn't believe it until I tried it!