Oil Change
- Thread starter superdiver
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Our two FLs, as well as the Westerbeke genset, have hoses attached to the bottom of the pan for draining the oil. From the factory? I don't know, but sure makes it easy.
On our last boat I made up a drain plug with a hose fitting and used that to suck the oil out. Of course you need access to the drain plug to do that.
Bob
On our last boat I made up a drain plug with a hose fitting and used that to suck the oil out. Of course you need access to the drain plug to do that.
Bob
Nomad Willy
Guru
Bruce,
I don't think the the VW mechanic uses the extractor on a regular basis but I don't know and my wording was probably misleading. It was I just reread. Sorry
Ron,
Willy's Mitsu has a hose attached to the drain plug that has it's own extractor pump attached so I just put a container under the pump outlet curved tube on top and start pulling the pump rod up and down. And as FF says the oil is very hot. I know most boat engines have drain plugs that are very difficult to get to but the VW guy proved that all the oil was extracted in the VW car. I suppose that suggesting TF members do that was a bit stupid. But getting 95% of the oil out is all we do anyway because of oil left in the engine. The idea of changing oil in the first place is that we replenish enough of the oil that's got some time on it w fresh oil so the oil is able to do it's job. So if the oil can do it's job 100% satisfactorily w 95% (or so) of the oil exchanged at recommended intervals the oil change is 100% effective. The idea being to have "mostly" clean oil "100% of the time. The idea of every spec of oil needing to come out during an oil change is ... over fussy .. anal .. over the top ..
FF yes it's amazing how fast the hot oil flows through the small tube. I recall when I first encountered the concept of extracting the lube oil out through a tube small enough to insert into a dip stick hole I must have said something like "you gotta be kidding". But it works very well.
Ron wrote; "In the slip idling, I can't get the engine over 150 degrees or so." Engines are different in this respect. After a few minutes of idling my Mitsu gets up to 180 and only gets a few degrees warmer at 2500rpm cruising. The degree of control afforded by the thermostat varies. And the location and plumbing in the vicinity of the thermostat varies too. My engine runs at 50% load most of the time so I'm glad the thermostat seems to "pick up the ball" so to speak to help keep the engine warm enough. I suspect most trawlers would be better off w/o an oil cooler while running at 30% or so. But if you ever worked the engine hard you'd want the oil cooler back. So I'm not implying one should do that. I probably would do that w an overpowered boat .. and most are.
I don't think the the VW mechanic uses the extractor on a regular basis but I don't know and my wording was probably misleading. It was I just reread. Sorry
Ron,
Willy's Mitsu has a hose attached to the drain plug that has it's own extractor pump attached so I just put a container under the pump outlet curved tube on top and start pulling the pump rod up and down. And as FF says the oil is very hot. I know most boat engines have drain plugs that are very difficult to get to but the VW guy proved that all the oil was extracted in the VW car. I suppose that suggesting TF members do that was a bit stupid. But getting 95% of the oil out is all we do anyway because of oil left in the engine. The idea of changing oil in the first place is that we replenish enough of the oil that's got some time on it w fresh oil so the oil is able to do it's job. So if the oil can do it's job 100% satisfactorily w 95% (or so) of the oil exchanged at recommended intervals the oil change is 100% effective. The idea being to have "mostly" clean oil "100% of the time. The idea of every spec of oil needing to come out during an oil change is ... over fussy .. anal .. over the top ..
FF yes it's amazing how fast the hot oil flows through the small tube. I recall when I first encountered the concept of extracting the lube oil out through a tube small enough to insert into a dip stick hole I must have said something like "you gotta be kidding". But it works very well.
Ron wrote; "In the slip idling, I can't get the engine over 150 degrees or so." Engines are different in this respect. After a few minutes of idling my Mitsu gets up to 180 and only gets a few degrees warmer at 2500rpm cruising. The degree of control afforded by the thermostat varies. And the location and plumbing in the vicinity of the thermostat varies too. My engine runs at 50% load most of the time so I'm glad the thermostat seems to "pick up the ball" so to speak to help keep the engine warm enough. I suspect most trawlers would be better off w/o an oil cooler while running at 30% or so. But if you ever worked the engine hard you'd want the oil cooler back. So I'm not implying one should do that. I probably would do that w an overpowered boat .. and most are.
FF
Guru
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So if the oil can do it's job 100% satisfactorily w 95% (or so) of the oil exchanged at recommended intervals the oil change is 100% effective.
The oil always does its primary job , lubrication, and secondary , heat transfer.
Oil is changed so the additive package 15% to 35+% of the oil is renewed.
Changing also allows the detergents in the oil to carry off the crud , and the dead acid modifiers to be replaced.
Oil never wears out , but the good stuff does.
That is why oil that uses secondary cleaning , centrifuge , or simply massive filters ialso needs replacing.
Sadly ideling at the dock till the oil is simply warm before changing will not capture the fines that pass thru filters , it takes hours of higher temps and lots of oil flow to loosen and carry off the gunk.
It may no longer be like a grinding compound from the trapped dirt , but the rest of the chemicals require replacement.
The oil always does its primary job , lubrication, and secondary , heat transfer.
Oil is changed so the additive package 15% to 35+% of the oil is renewed.
Changing also allows the detergents in the oil to carry off the crud , and the dead acid modifiers to be replaced.
Oil never wears out , but the good stuff does.
That is why oil that uses secondary cleaning , centrifuge , or simply massive filters ialso needs replacing.
Sadly ideling at the dock till the oil is simply warm before changing will not capture the fines that pass thru filters , it takes hours of higher temps and lots of oil flow to loosen and carry off the gunk.
It may no longer be like a grinding compound from the trapped dirt , but the rest of the chemicals require replacement.
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Nomad Willy
Guru
FF good post.
You wrote;
"Oil never wears out"
I don't know one way or an other but I have heard many times that what makes oil slipery is that it is made up of very long molecules. And as the oil is thrashed probably most harshly in gears the molecules are choped up shorter and over time the oil looses it's slippery quality .. lubricity I guess. But the ability to carry heavy loads like in main and rod bearings may or may not be related to lubricity and how the length of the oil molecules effects oil performance .. I don't know. But it's hard for me to "visualize" oil being thrashed badly for a long time and not suffer any change in physical properties and such changes should change and effect how an oil would perform as lubricating Oil.
So it would seem to me oil should have a tendency to wear out.
You wrote;
"Oil never wears out"
I don't know one way or an other but I have heard many times that what makes oil slipery is that it is made up of very long molecules. And as the oil is thrashed probably most harshly in gears the molecules are choped up shorter and over time the oil looses it's slippery quality .. lubricity I guess. But the ability to carry heavy loads like in main and rod bearings may or may not be related to lubricity and how the length of the oil molecules effects oil performance .. I don't know. But it's hard for me to "visualize" oil being thrashed badly for a long time and not suffer any change in physical properties and such changes should change and effect how an oil would perform as lubricating Oil.
So it would seem to me oil should have a tendency to wear out.
BruceK
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My MDKD Onan 6.5 has a rubber oil drain tube with valve. But the Onan sits in a frame with raised edges about 3/4" so the hose is slightly uphill if trying to drain oil. But it might be more effective to put the dipstick extractor tube down the rubber tube than the dipstick hole. I`ll try it next time. Sump gunk beware.
psneeld
Guru
My Westerbeke has the same...but someone (PO or installer) drilled a hole in the frame, and there is a second piece of tubing with a fitting that screws onto the drain line fitting where the cap usually is.
So all I have to do is put the second tube (now long enough to reach the bottom of the bilge so I don't have to hold a container) through the hole, screw it on and pull it down so everything drains.
Vashon_Trawler
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I also own the Jabsco engine oil pump and had difficulties at first, but it works very well now. As others noted, it is best to change the oil after the engine reaches operating temperature (or close to it). Don't let the engine idle but rather change the oil after a day trip for example--it will flow far better. Even with warm/hot oil, the pump takes time to drain my 4.5 quart pan. Also, the hose that came with the pump was slightly too large for my dip stick tube; it would get stuck and kink. I had to replace the entire hose to create a better fit.
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Newbie
I have a manual pump but flexible plastic tube which curls up in oil pan. My best result was attaching a piece of copper tubing to plastic tub, yes with electrical tape, then rigid tub hit the bottom of oil pan. Works well, just a little crude. 135 Lehman in Albin 36
0 Regrets
0 Regrets
