Oil Change Question

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jamoore

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I am the relatively new (couple months) owner of a Mainship 40 with twin Yanmars. Getting ready to do an oil change. Each engine has a gray plastic/rubber hose fitted to the oil pan. They are a couple feet long and just have a plastic plug shoved into the open end. Is an added on item or was this a factory option? More importantly, will I be able to gravity drain the old oil or will I need some type of pump assist. Looks like I can get a container to sit in the bilge lower than the oil pans. Not 100% sure since the bilge is not flat. Not sure how low the catch container will actually sit. Anyone got this similar system or familiar with it? That plastic plug just pushed into the open end is a little scary to me but surveyor or my agent never commented on it. Thanks in advance this site has been very helpful to a new owner.
 
I have a 12 volt pump that I use to drain the oil. My Lehmans have a drain fitting on the oil pan drain plug. I hook the pump to the hose connected to the drain fitting and open the valve at the drain plug. Turn on the pump and wait a couple of minutes and the 4.5 gallons are gone. I could not gravity drain the oil, no room for a 5 gallon bucket to drain into.
 
I think I would for sure correct that plug in the end of the hose. If it was to vibrate out while you are under way, you will have a big mess to deal with (if you catch it before the engine seize's up )
 
If the top of the hose is above the oil level in the pan and when you rock snd roll, it is fine....as it probably has been for quite awhile.

Just make sure the end of the hose is secure, as gravity, not the plug is keeping tbe oil in the pan.

If nervous about it, a brass barb with threads and a brass cap is a little more secure.
 
Many marine engine users have a similar hose. As psneeld said: have the top of the hose fastened above the oil level. I have a valve on mine.
I, like a lot of people have a plumbed in pump. I can drain my 4 diesels (mains and 2 generators) in less than 5 minutes to a tank that can be pumped out from the main deck. Most commercial fuel docks have waste oil pump out services. They also have a long hose and tube that goes down the dipstick tube for oil changes.
 
There might might be a small ball valve fitted to the oil pan, and the plug at the end of the hose is just a backup stopper.

At least that's the way I would want it.
 
I never had such an item on any of my Yanmars until I installed them myself. I would route the hose up the side of the engine were it was mechanicaly fasted to the engine so the end of the hose would be above the oil level as previously stated by Psneeld. In those days I used a simple 12v pump and a 5 gal bucked to suck the oil out of each engine.


To answer your question about gravity drain. It will gravity drain into your bildge when you don't want it to, but I doubt you will get it to gravity drain into a bucket. its just how boats work.
 
Pump it out warm. Forget the gravity drain idea. What would be big enough to fit underneath that you could remove cleanly when full?
Perhaps there is a pump stashed away in a big ziplock bag?
 
I could have installed an electric sucker pump, but like keeping my engine room un-cluttered. Takes about ten minutes with a hand pump to suck the 5gal from the main, and 3/4gal from the gennie. Just attach sucker to the pigtail hoses on each engine. I pump it into 2.5gal rotella jugs which are easy to handle. Easy to pour in new oil with one gal jugs.
 
I,ve done both the hand pump from the bottom of the oil pan (installed) and the vacuum pump by hand w small dia plastic tubes down the dip stick hole.

Both are very effective. The vacuum extracror is easier but takes more time. Never done either when oil is cold. However the little fuel pump would be handy and offer a greater capacity for oil. Actually if I had two big engines the capacity issue would probably drive me to the electric pump. Not a need then but a convenience.
 
Thanks to all. I knew I would get some great feedback. Any suggestions or recommendations on an electric pump for sucking the oil out? I have seen a few advertised but would welcome recommendations from users. Joe
 
I use one of these...

31KNWRA4RTL.jpg
 
First thing to ensure is that there is an oil pan mounted shut off valve. Lockable ball valves are available so no accidental openings will occur.

I would also figure out how to tie the existing hose end up and out of the way , even if there is a shutoff, so now oil won't leak out into the bilge if that plug comes unplugged. There will be residual oil in the hose and it does not take a lot to make a mess.
 
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I have thought about a shut off valve...but I have run dozens and doesens of older boats without them

As long as the drain hose remains in even fair shape....the valve is nice but not really needed or all that common.

Dont get ne wrong, I might still add one, but it isnt an urgent mod.
 
I do not see the need for a valve in the pigtail. A good quality hose with good fittings, capped at the bitter end, is all that is needed.
 
I have SP225s that take 22 quarts. I have a Jabsco pump that came mounted on a 3 gallon bucket. I took it off the 3 gallon bucket and use it stand alone. It works great. It has clips that go on the battery terminals. Mine has a valve on the oil pan to shut off and about 20” hose with screw on caps to act as a secondary seal. I take the cap off the hose and screw the hose to the pump onto the hose from the oil pan and then open the valve on the oil pan. Turn on the pump and direcr the discharge into a 5 gallon bucket. Easy. Quick.
 
I use one of these...

31KNWRA4RTL.jpg

Al,
I’ve used those for years.
They are great if you over fill your car. Or have another reason to extract a quart or two from an engine.
 
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I use one of these...

31KNWRA4RTL.jpg
Those things really suck! Our marina mechanic leaves it connected overnight, gets the last dregs out of the sump, oil stays cleaner longer.
I had a Perkins T6354, it had a built in pump which worked a treat. When I see Perkins pics they often have a pump,maybe it was a Perkins "perk".
 
I have twin CATs. 4 gallons and 2 filters per engine.
 
oil changing system

I installed a reverse oil changing pump. It has three manifolds for the twin engines and the genny. Just heat up the oil, turn the appropriate valve and it the pump empties the engine in about two minutes. You can even fill it the same way. Never a mess.

Peter
Schatzi
2000 MS 390 twin
 
I'm interested in the fitting for the oil pan plug on a Lehman 80 so I can setup this way and pump from the bottom of the pan. Anyone know a part number for that piece to replace the oil pan plug with so I can attach a hose?
 
Harbor Marine in Everett Wa. would have that item I think.
Ask for Mike.
 
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