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Oil change via the hose extension out the bung hole.

deejaycee_2000

deejaycee_2000

Banned
Hi guys, I have browsed the internet far and wide to find a step by step instruction on how to drain my Mercruiser 4.3L Mpi oil via the extension hose that you route through the bung hole to drain but come up with nothing, there are load of videos on how to pump the oil out via the dipstick but I do not have a pump and would prefer draining it as I described above. Has anyone done it this way before?
 
IF your dipstick holder (tube the dipstick goes into) has a water hose-like male thread about the tube, then you can buy a simple hand pump that screws onto that thread. A few pumps and out the oil right comes. Works excellently.

Jeff
 
Thanks Jeff I considered buying a pump, but I would like to drain the oil over the course of 2 weeks as my towing vehicle is at the shop for at least another month so I can't warm up the engine and need to drain it cold. So this method is my only option at this stage.
 
Get (borrow) a heat gun. Turn it on and push in the button that keeps it running. Throw it in the bilge pointed at the oil pan. Go have lunch. Come back and do oil change.
 
If you now have a hose that is connected to a low point on the oil pan, you can connect the Tempo Oil Boy Extractor to that hose and draw the engine oil out. (it may require some type of fitting in order to connect to your hose fitting)

It's very easy and it is not messy!
It works best when the oil is warm!
As you pump the handle, vacuum is created within the container.
The vacuum pulls the oil up and into the container.


Tempo Oil Boy Extractor.jpg


The Oil Boy offers other uses as well!
 
o2batsea said:
Get (borrow) a heat gun. Turn it on and push in the button that keeps it running. Throw it in the bilge pointed at the oil pan. Go have lunch. Come back and do oil change.
Click to expand...

And call your insurance company and let them know that you are about to do this! :(
 
chicken Keep in mind that Rick's a Volvo guy so he's all belt, suspenders, and structural engineering. Just don't point the heat gun directly on anything flammable like Rick's sense of propriety :). just need to warm the bottom of the engine where the pan is.
On more than one occasion I have jut pulled the drain plug on the pan and let it goosh into the bilge and put a pan under the back of the boat to catch it. After the weather warms up a little Dawn will clean up the little bit of oil left in the bottom of the boat.
 
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o2batsea said:
chicken Keep in mind that Rick's a Volvo guy so he's all belt, suspenders, and structural engineering. Just don't point the heat gun directly on anything flammable like Rick's sense of propriety :). just need to warm the bottom of the engine where the pan is.
Click to expand...

o2batsea, it has nothing to do with Merc, Volvo Penta, PCM, OMC, Indmar, etc.
It has to do with this:

Get (borrow) a heat gun. Turn it on and push in the button that keeps it running. Throw it in the bilge pointed at the oil pan. Go have lunch.
Click to expand...
 
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My motor does have the oil hose extension with the tether on it and it will easily reach through the bung hole, I am just not sure of the procedure, guess I will just figure it out, maybe I should make a video ... it is already summer here (34 degrees Celsius average) so no doubt it will drain out completely over time, my boat is just parked in such a way that I cannot run the motor as it is in my garage. I would also like to see if there is any debris hiding in the bottom of the oil pan, doubt a suction pump gets it all out clean.
 
I didn't notice that you were in ZA. yeh, just point the hose out the bung and leave it. Couple days it'll be fine. There's always going to be some oil left in there (which is a good thing) so even if you don't get out every last drop of the old it won't be a problem. I guess you can probably forget about the heat gun thing! Now Rick can go back to DEFCON 2 as it don't look like deejaycee is going to melt or explode his vessel any time soon.
 
The first step, remove bung plug ( do not misplace). Secondly, get down deep in the stern and stick the hose (that you already have on your motor) through the bung to the outside, Then remove the plug from the end of drain hose (do not misplace) and allow oil to drain (in suitable enviro-freindly container). Two weeks should be ample time for most of the oil to drain out. Special note.....now would be a good time to change out the oil filter (prefill if you'd like) and make sure the old filter's gasket does not stick to engine. One gasket per filter is what is required.

Finally replace drain hose plug, pull hose back into boat and properly stow, refill your motor with proper amount of new oil.
 
Whether it be a lawnmower, car or boat engine...Oil should always be changed hot. My personal belief is that wax like sludge substances and condensation are left behind during a "cold" oil change. I never let the engine cool down for more than a few minutes before removing the drain plug or pumping it out through the dipstick. If you're worried that the dipstick mounted suction pump will leave some oil in the pan, you can add another sacrificial quart after the initial "pump out" and then pump that out to fully remove any dirty oil. In your situation, I don't think that leaving the oil unchanged until you get your truck back would be a problem.
 
My compliant is the the boat drain plug (bung hole?) diameter is not big enough for the oil drain hose extension, cable, etc. Good idea but poor design between hull and engine manufactures. Boat drain plug size needs to be increased. (I think this issue has been discussed quite a bit.)
 
I would just go the hardware store to get a reducer fitting to adapt the drain hose to a smaller diameter that would fit the bung hole then. Use your imagination.
 
sab said:
My compliant is the the boat drain plug (bung hole?) diameter is not big enough for the oil drain hose extension, cable, etc. Good idea but poor design between hull and engine manufactures. Boat drain plug size needs to be increased. (I think this issue has been discussed quite a bit.)
Click to expand...

Forget using the garboard drain and gravity.

Lift the drain hose up.
Connect the drain hose to your Tempo Oil Boy Extractor.
Pump the handle a few times and sit back!

It doesn't get any more simple!
 
Many Inboard ski boats use the hose drain at the bottom of the oil pan and that works fine,
Inboard ski boats typically have a thru hull drain very close to the engine.

If yours has this hose it is should be designed to feed out the transom drain. Just get the hose thru the hole unscrew the plug and let it drain into a pan/bucket.

This will drain almost every bit of oil as the fitting is at the lowest point on the oil pan.
 
Jack exactly my point, thanks, just not easy to "feed out the Transom drain", need two people
For those interested

Transom Drain Hose Kit-Oil Drain Assembly
P/N 32-865281A02 replaces
P/N: 32-805505A2
Transom Drain Plug Plugs Tether Assembly Kit,
p/n 862827

 
sab said:
My compliant is the the boat drain plug (bung hole?) diameter is not big enough for the oil drain hose extension, cable, etc. Good idea but poor design between hull and engine manufactures. Boat drain plug size needs to be increased. (I think this issue has been discussed quite a bit.)
Click to expand...

That is correct, all US boats have the small drain, I now remember, although not alot of US boats around here, mine has a 30mm drain hole so it fill fit right through.
 
Some people reading this thread may get the impression that the bung (drain) hole is there for the purpose of draining engine oil. Not the case. It called a drain hole for reason so that when the boat is out of the water it can be removed so any bilge water or subsequent rain water will not fill the boat and cause it to sink on land. If the drain hole were made much larger to accommodate an oil drain hose (or any other reason) just imagine how many boats would sink soon after being launched and someone "forgot" to install the bigger drain plug. If you want to DYI your oil change get the proper equipment and do it the right way!
 
On the contrary, you haven't had a boat unless you forgot to do that at least once ;) .... and it only happens once, then you will never forgot again ....
 
If his oil pan is equipped with the drain hose set up he will be fine. If not get the "proper equipment".........



People forget drain plugs all the time even professionals...........Sh!t happens.
 
i have changed the oil in many boats with that drain hose, all of gthem fit through the drain plug hole, some took a bit of finess but they all fit.
that being said, the oil has to be real warm/hot to flow through the hose by eway of gravity. dont forget. there is always oil left in the hose, which never get worm so the first bit of oil will be real slow to dribble out.
i dont understand why so many posters kept going back and talking about the extractor. the guy said he didnt have one. the drain hose works but it is very slow to drain.
the idle process would be to hook up an electric pump to the drian hose, you will most definetly get most if not all of the old oil out. and for those who's hose wont fit through the drain plug, the electric pump would be good for you too. you can do it from inside the bilge.
 
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