Electric Oil Change Pump

[geoffschultz]

I'm building a Knysna 550 cat, and I would like to permanently install electric oil pumps to change the oil. It will have Yanmar 4JH80 motors which will be installed under the berths. I have too much experience spilling used oil, and want to minimize my chances of repeating that (and keep the admiral happy...)

From what I can see in the parts manual, there are 2 drain plugs in the oil pan. I would assume that there's a fitting that could be installed in one of them that would connect to a hose that goes to the pump.

What kind of hose should be used?
Do people have recommendations for the pump?
And what else do I need to be aware of?

-- Thanks, Geoff

[wrwakefield]

Hi Geoff,

Be aware that once you go this route, you will never go back to manual oil changes… [Not unlike having a washer/dryer…]

We have a home-made manifold of ball valves for selecting which engine [main, gen, and a 3rd valve for a 10ft long pick-up hose for any use] to drain/fill with oil. We are using a reversing Johnson fuel transfer pump that has an impeller.

Reverso offers ready-made manifolds with gear pumps built-in for a slight premium over configuring your own.

We use Type A fuel hose for the flex lines. Hydraulic hose would also work.

I always recommend fitting a purpose made oil pan drain valve if you can reach it to open and close as a hedge against an oil drain hose failure in the future. e.g., Fumoto or similar. They are available to fit most engines and in many configurations [e.g., straight, 90°, etc; image appended below.]


Two hints:

-You can drain and fill using the pump. [Filling is slower unless you can pre-warm the oil…] Very handy, but remember to lift the dip stick or oil filler cap before doing either to allow for air displacement.

-Consider installing a hose on one of the manifold ports long enough to reach under the engine and into the bilge[s] for vacuuming up any future oil spills. It is also great for inserting a smaller tube for draining transmissions and portable engines via their dip-stick tube.

In case any of this is useful.

Cheers, Bill

[dannc]

Originally Posted by wrwakefield

...
I always recommend fitting a purpose made oil pan drain valve if you can reach it to open and close as a hedge against an oil drain hose failure in the future. e.g., Fumoto or similar. They are available to fit most engines and in many configurations [e.g., straight, 90°, etc; image appended below.]...

Cheers, Bill

Yep, I highly recommend Fumoto drain valves. I have used the one on my truck for 20+ years. Bought the valve decades ago and it made oil changes that much faster and easier. The Fumoto value also meant I no longer had to keep a supply of washers to use when changing the oil.

[scherzoja]

I had a Reverso, but replaced it with a Marco pump gear pump because the Reverso flexible impeller kept failing between oil changes. It hardened up and the vanes broke off when I tried to use it. Got tired of $50 annual expense for replacement impeller. Also, the Reverso impeller pumped only warm fluid, so I could not use the pump to fill the oil.

Reverso model: Reverso OP6FV
Marco model: M164-022-12 (installed, but not used, so can't tell you if it works)

I used hydraulic hose to go from the main engine oil pan to the 3 way valve (the 'manifold'). Connected to the oil pan with a banjo fitting (not much room under the engine). It is impossible to reach the oil pan drain plug when engine is installed, so I did all this when I had engine out for rebuild. Because of the inaccessibility when installed, I chose hydraulic hose for the chafe resistance. It's a bit stiff and if the ends are installed in wrong orientation, you really can't twist the hose much to make the ends line up.

Generator will also be plumbed the the Marco pump and it has one of the those Fumoto valves and will be reachable when installed. This is good because I can be sure that the oil will remain in the motor if the hose leaks. Don't have that assurance with the main engine. I will use a more flexible hose (probably A1 fuel hose) for the generator's oil drain.

Carefully check the oil pan plug threads (metric, imperial, or BSP, ORB?). It'd be a bummer if you forced the wrong threads in there.

At the pump output, I installed a quick disconnect so I can clean and store the output hose after use.

McMaster part numbers:

https://www.mcmaster.com/5316K39/
https://www.mcmaster.com/5316K13/

[Madehn]

I used a as ball valve and fuel hose. Valve location is inaccessible so I fabricated an extension to the valve handle using a piece of aluminum angle iron and a 1/4 inch bolt with nyloc nut as a swivel / hinge. Pump is a seaflo gear pump with a small filter prior to pump. Engine holds 11 quarts and this makes it easy.

[wrwakefield]

Originally Posted by scherzoja

I had a Reverso, but replaced it with a Marco pump gear pump because the Reverso flexible impeller kept failing between oil changes…

What a pain that would be. My Johnson impeller fuel transfer pump has been flawless for 20+ years.

I just wanted to mention that the Reverso I installed in a friend’s boat a couple of years ago was a gear pump. I haven’t followed-up to see if that is an option or something they changed to/from, but wanted to mention it.

Good ideas on the quick disconnects. Since I also add the new engine oil using the pump, the hoses are always stored in place clean and clear, and in 20+ years have never had any issues with them plugging/gumming-up.

Note to OP: Don’t forget to add confirming that all oil change manifold valves are in closed position to your pre-flight checklist.

Cheers, Bill

[geoffschultz]

Note to OP: Don’t forget to add confirming that all oil change manifold valves are in closed position to your pre-flight checklist.

That most likely won't be an option, as access to the engine will be from the top, and I suspect reaching a valve on the oil pan would be next to impossible.

[Shrew]

Originally Posted by scherzoja

I had a Reverso, but replaced it with a Marco pump gear pump because the Reverso flexible impeller kept failing between oil changes.

My Reverso has a gear pump. I replaced an 'X-Chang-r' system which had a Jabsco impellor for the exact reason you describe.

My Reverso with a gear pump has worked flawlessly.

[geoffschultz]

Originally Posted by geoffschultz

Note to OP: Don’t forget to add confirming that all oil change manifold valves are in closed position to your pre-flight checklist.

That most likely won't be an option, as access to the engine will be from the top, and I suspect reaching a valve on the oil pan would be next to impossible.