OIl Changing Aids - Pump or Vacuum ???

Which is better for changing engine oil in an inboard.

Vacuum



Or manual pump

I have tried a few different techniques, including a vacuum system, a 12V pump, and the cheap manual pump. What has ended up working best for me is the cheap pump.

The vacuum system nothing but trouble. Mine was different than the one pictured, but I can believe the problems are similar. The basic problem is that it is a lot harder to pump air than it is to pump oil. Any leaks in the system and getting a good vacuum is impossible.

The 12v system was just way more trouble than it was worth. The container it came with was unsuitable for transporting the used oil, so I had to transfer it to another container, then there was a LOT to clean up.

I finally settled on a cheap hand pump. I also bought a regular gas can, painted OIL on the sides of the can and use that for the used oil container. I installed a hose barb into the side of the can so that I could connect the pump directly. It is simple to hook up, it only takes a minute to pump the oil out. Once I am done, I disconnect the pump from the hose going to the can, leaving that hose attached to the OIL can. The other hose I wrap back up to the now open fitting on the pump, making it a sealed unit. This leaves used oil in the pump, but who cares. The oil can can now be carried in the car for easy disposal.

i just switched to the vacuum, just like the one in your picture. i've only used it twice but it was so much easier than the hand-held drill pump i used to use. i didn't have any problems getting a vacuum so it was super easy. 3 or 4 pumps and the vacuum just keeps pulling oil up, it's easy to get carried away and over-pump. there's a release valve like on a keg to release the pressure. keeping the oil self-contained was even better. lifting the entire pump out, with oil and all hoses, was a nice change.

i've never tried the manual pumps.

I'm leaning toward the manual. How long does it take? I have a 4.3l that holds about 4 litres of oil.

I bought a cheap 12v pump from JC Whitney about 15 yrs ago (think I paid about $15), and pump the oil straight into a 1 gal milk jug. Yes I have to switch jugs half way through - no biggie. I put both jugs in a cardboard box and crimp the hose and move it quickly. The only pain is that you have to prime the pump, but it's not that hard. The pump is not the fastest thing going, but it works.

The vacuum pumps made out of plastic shown above is tested hundreds of times over by auto shops. I have used one in the past for every type of fluid imaginable and have never had a problem.

why not upgrade your drain line so all you have to do is pull the bilge drain and pull the engine drain hose through the hole into a drain pan??

Bob,
I was planning to change the oil dock side just before I drive the boat to the marina for storage.

Rod,
why did you stop using the 12Vdc pump?

Peter,
The vacuum might be nice as long as it's not fussy. Does tube you slide down the dip stick pipe stay at the bottom or do you have to play with near the end of the pump out to get the last of the oil?

As well, I have a Honda four stroke 9.9hp motor. The oil drain is on the side of the motor. Using it always results in the last 5% of the oil running down the side of the motor. IS the vacuum line small enough to fit down a regular dip stick pipe?

Everyone,
I found a garage in the area that will take the used oil. I'll either have to pump it right into a container that I can leave at the garage (we use spring water so there are lots of 4 and 11 liter jugs around) or transfer it into a container

I think I have the best solution. I have a Pela vacuum pump (the round one) - and I remove the part of the hose on the pump that goes down the dipstick hole (it's black and relatively inflexible). The remaining plastic piece is the EXACT size as the drain hose (the one you put through the hole). I simply attach that plastic piece to the drain hose and suck it all out. I know I am getting all of it because it's coming from the bottom of the pan. For the filter, I take a zip loc freezer bag (1 gal size), put it over the filter, unscrew the filter and let it drop into the bag. Then zip the bag closed and remove. This process is simply with no spillage.

James wrote:
Rod,
why did you stop using the 12Vdc pump?


I had borrowed it from a friend. The pump, a reversible rubber impeller Jabsco model, was mounted to the lid of a 5 gallon bucket. It was big, messy, TOP HEAVY, and just in general a pain.

As far as disposal: We have curb side recycling at my house and you can put "approved" containers out for the trucks to pick up. They are supposed to empty the container into their tank and leave the empty for you. I tried it twice: The "approved" container is exactly like the milk jugs. The first time I used the approved container and some jerk walking down the sidewalk decided to give the jug of oil a kick, and then I had a big mess to clean up.

The second time I tried curbside I used a much better, "kick proof" container. The recycler took it!

Now I have my 5 gallon gas can, clearly labler "OIL" and I take it to the local auto parts store (Kragen) and they will take it, no charge.

pump in top picture = GOOD

pump in bottom picture = BAD

Keith just posted the prefered process.

I agree with Bob. I run the motor till it reaches normal operating temps, drop the drain plug hose through the bilge hole into an oil pan, change the filter, come back the next day and fill it up.

The drain plug hose method does take a long time to drain, which is why I leave it overnight, not a big deal.

-gvb