Well the Honda outboard I have does not even sport a FF filter. So I was thinking of installing a BMK 21. I will take psi from the idiot oil light switch and return to the fill cap. I was wondering if the BMK 21 has a resistor because I do not know how much capacity the oil pump has in this motor?
BMK 21 On Honda BF 15 Outboard
- Thread starter John With Beastly 302
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The 21 is the renamed 11.
It uses this mount:
BK-203
Filter mount assembly with restrictor, .032" orifice BMK-11 (21)
It's the same restrictor size that's in the cheaper BP80A. I verified this with technical.
Side note: When I got my BP80A ..I thought that they left some assembly tool aid in the filter thread. Then I saw that it was one cast piece. I then saw a "spot" in the middle. I then took it into work and pinned gauged it @ .029. I needed them bifocals that day.
It uses this mount:
BK-203
Filter mount assembly with restrictor, .032" orifice BMK-11 (21)
It's the same restrictor size that's in the cheaper BP80A. I verified this with technical.
Side note: When I got my BP80A ..I thought that they left some assembly tool aid in the filter thread. Then I saw that it was one cast piece. I then saw a "spot" in the middle. I then took it into work and pinned gauged it @ .029. I needed them bifocals that day.
dnewton3
Staff member
Zowie! I bypass filter on a 15hp outboard motor; a Honda at that. Now I've heard (just about) everything ...
I would estimate between the lines, adapter, fitler element, you've possibly doubled the sump capacity? Are you going to hang it on the motor, or run lines down the tiller and transom, and remote mount it? Just curious.
Just how much fishing (or whatever) do you partake in each season, that bypass filtering a Honda outboard makes sense? You probably ought to run PAO synthetic oil, too, just to be on the safe side. You know, so that you don't wear it out too soon. (OK - I'm poking fun at you, I know; I don't mean any disrespect. But doesn't this seem like just a wee bit of overkill?
).
Still - I'd love to see pix if you follow through on it. This would certainly be a more unique application, and worth posting on the Amsoil website.
I would estimate between the lines, adapter, fitler element, you've possibly doubled the sump capacity? Are you going to hang it on the motor, or run lines down the tiller and transom, and remote mount it? Just curious.
Just how much fishing (or whatever) do you partake in each season, that bypass filtering a Honda outboard makes sense? You probably ought to run PAO synthetic oil, too, just to be on the safe side. You know, so that you don't wear it out too soon. (OK - I'm poking fun at you, I know; I don't mean any disrespect. But doesn't this seem like just a wee bit of overkill?
Still - I'd love to see pix if you follow through on it. This would certainly be a more unique application, and worth posting on the Amsoil website.
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Well, he has zero filtration now ..and no easy method to add a full flow. I'd say that while a bypass may be way overkill ..that it's the only show going for this type of setup.
dnewton3
Staff member
Yes, I realize that there's no filter on this little engine. But the same can be said for hundreds of thousands of little air or liquid cooled engines with either splash or forced lubrication for four cycle engines. And there's obviously no practical way to filter wear metals from 2 cycle engines. And yet, they all just keep on running.
I expect Honda looked at this boat motor, and reviewed the wear patterns, wear rates, and "typical" seasonal use factor, and decided a filter just wasn't necessary for expected long life. I cannot think of any example that I'm aware of, either directly or indirectly, where a Honda engine stopped because of a perceived lack of filtration of it's lube system. Granted, there are plenty of engines that fail from too little or too much lube. But engines that are maintained according to the OEM specs? Nah - you just don't see those fail.
I looked at the Honda Marine website; the owner's manuals are available for viewing online. The older engines (with squarish motor hoods) don't use fitlers. The newer engines (with rounded motor hoods) do use filters. So presumably he has an older one. But I looked at one from each generation (of the four series listed) and observed the following:
they all have about 1.1 to 1.2 quarts oil capacity
they all have OCIs at 100 hours, regardless of filtration system being present or not
they all use 10w-30
So, it seems like the little engine from yesteryear is just about as capable as today's. Clearly Honda thought is was a good idea to add a filter; they would not have added cost and complexity for the joy of it without some ROI. But let's still look at this at face value. Adding the fitler didn't gain any appreciable OCI distance. Same sump capacity. Same oil grades. The OCI is 100 hours or every 6 months, regardless of generation of engine. I already asked the OP just what useage the motor was expected to endure? We have no indication that the 100 hours would even be usurped in a single season. Typically, those of us on BITOG have many engine-driven interests. Even if John-302 is retired and fishes daily, would he surpass the 100 hours in a season? He's probably like the rest of us, and goes fishing one week, drag racing another week, motorcycle riding another week, etc. While he's constantly in a motor driven conveyance, any one of them may not accumulate high usage for the season. Again, he could let us in on his dirty little secret, but he hasn't. So, I am left with assumptions from here on. Is this motor on a small fishing boat? Does it see frequent start/stop cycles? Is it pushing a sailboat out to sea, and only sees infrequent use? Is it used to ferry people to/from houseboats? Inquiring minds want to know!
I have three Honda pieces of equipment. A Goldwing (forced lube). Also a GX190 air cooled 4 cycle on my utility cart (cheap version of a 'Gator), and a little 4 cycle mini-rototiller. The latter two are splash lube'd. Clearly splash lube is inferior to forced lube, in general. And yet, these motor on with no signs of stopping. Just annual OCIs, with no filters.
I don't condem Mr. Beastly 302 for wanting to play and experiment. But he'll be "adding" lifecycle to the "little engine that already could".
He could gut the filter internally, and still take the life cycle out infinitely just because he's probably doubling the sump capacity. Add the bypass element media and he's heading "To infinity, and beyond" (credit Buzz Lightyear!).
And let's look at the cost involved. BMK set-up, plus annual filter costs, and extra oil costs. Compare that to no oil filter, and about 1 quart of the standard sump fill.
Just because he can do it, doesn't mean he should do it. There's just no "percievable" gain to it. My prediction is that he does it for the fun of it. And then a few seasons from now the BMK ends up on E-bay, or some other venture, because he'll realize the time/money/effort spent on this little outboard is wasted because it already will outlive his use for it.
Now, if he's trolling for clams for 8 hours a day, all summer long, and wants to extend his OCI for the sake of the OIL (rather than the motor), that's entirely different. It might actually make sense. But man, that's a lot of time in a little boat ...
I expect Honda looked at this boat motor, and reviewed the wear patterns, wear rates, and "typical" seasonal use factor, and decided a filter just wasn't necessary for expected long life. I cannot think of any example that I'm aware of, either directly or indirectly, where a Honda engine stopped because of a perceived lack of filtration of it's lube system. Granted, there are plenty of engines that fail from too little or too much lube. But engines that are maintained according to the OEM specs? Nah - you just don't see those fail.
I looked at the Honda Marine website; the owner's manuals are available for viewing online. The older engines (with squarish motor hoods) don't use fitlers. The newer engines (with rounded motor hoods) do use filters. So presumably he has an older one. But I looked at one from each generation (of the four series listed) and observed the following:
they all have about 1.1 to 1.2 quarts oil capacity
they all have OCIs at 100 hours, regardless of filtration system being present or not
they all use 10w-30
So, it seems like the little engine from yesteryear is just about as capable as today's. Clearly Honda thought is was a good idea to add a filter; they would not have added cost and complexity for the joy of it without some ROI. But let's still look at this at face value. Adding the fitler didn't gain any appreciable OCI distance. Same sump capacity. Same oil grades. The OCI is 100 hours or every 6 months, regardless of generation of engine. I already asked the OP just what useage the motor was expected to endure? We have no indication that the 100 hours would even be usurped in a single season. Typically, those of us on BITOG have many engine-driven interests. Even if John-302 is retired and fishes daily, would he surpass the 100 hours in a season? He's probably like the rest of us, and goes fishing one week, drag racing another week, motorcycle riding another week, etc. While he's constantly in a motor driven conveyance, any one of them may not accumulate high usage for the season. Again, he could let us in on his dirty little secret, but he hasn't. So, I am left with assumptions from here on. Is this motor on a small fishing boat? Does it see frequent start/stop cycles? Is it pushing a sailboat out to sea, and only sees infrequent use? Is it used to ferry people to/from houseboats? Inquiring minds want to know!
I have three Honda pieces of equipment. A Goldwing (forced lube). Also a GX190 air cooled 4 cycle on my utility cart (cheap version of a 'Gator), and a little 4 cycle mini-rototiller. The latter two are splash lube'd. Clearly splash lube is inferior to forced lube, in general. And yet, these motor on with no signs of stopping. Just annual OCIs, with no filters.
I don't condem Mr. Beastly 302 for wanting to play and experiment. But he'll be "adding" lifecycle to the "little engine that already could".
He could gut the filter internally, and still take the life cycle out infinitely just because he's probably doubling the sump capacity. Add the bypass element media and he's heading "To infinity, and beyond" (credit Buzz Lightyear!).
And let's look at the cost involved. BMK set-up, plus annual filter costs, and extra oil costs. Compare that to no oil filter, and about 1 quart of the standard sump fill.
Just because he can do it, doesn't mean he should do it. There's just no "percievable" gain to it. My prediction is that he does it for the fun of it. And then a few seasons from now the BMK ends up on E-bay, or some other venture, because he'll realize the time/money/effort spent on this little outboard is wasted because it already will outlive his use for it.
Now, if he's trolling for clams for 8 hours a day, all summer long, and wants to extend his OCI for the sake of the OIL (rather than the motor), that's entirely different. It might actually make sense. But man, that's a lot of time in a little boat ...
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So?
I am not posting !!!
dnewton3
Staff member
Hey, I'd still be in line to see the pictures if he does it and posts them up!
Let's put aside my obvisous disdain for grotesque overkill, however, for the sake of discussion.
I presume the 15hp is on a small fishing boat. I just am having a hard time thinking how this could be done with user friendly-ness in mind. It's either going to hang off the engine in some atrocious manner (and possibly be a hazzard to itself or others), or it'll be down in the transom well near the battery and fuel tank, taking up space rightfully employed for empty beer can disposal.
I suppose he could mount it in some obscure place like a rod-storage locker, but then we're talking some serious length of hose for supply/return! Geez - just the capacity gain from this situation alone would make the sump last 10x probably.
Curiosity kills the cat; satisfaction brings it back!
Let's put aside my obvisous disdain for grotesque overkill, however, for the sake of discussion.
I presume the 15hp is on a small fishing boat. I just am having a hard time thinking how this could be done with user friendly-ness in mind. It's either going to hang off the engine in some atrocious manner (and possibly be a hazzard to itself or others), or it'll be down in the transom well near the battery and fuel tank, taking up space rightfully employed for empty beer can disposal.
I suppose he could mount it in some obscure place like a rod-storage locker, but then we're talking some serious length of hose for supply/return! Geez - just the capacity gain from this situation alone would make the sump last 10x probably.
Curiosity kills the cat; satisfaction brings it back!
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Originally Posted By: Steve S
I am not posting !!!
Why not??? You know how much they love you here...
IMO, I would seriously consider whether the engine has enough volume from the pump to support the additional scavenging.
Not to mention if the loss of oil from it priming (read: purging air) would be enough to starve it during a filter change. Air does flow differently through the orifice (even one this small) than the more viscous oil...and when talking a pump volume as small as we are...path of least resistance.
In this application, I would personally revert to more frequent OCIs than attempting to apply an external filter.
I am not posting !!!
Why not??? You know how much they love you here...
IMO, I would seriously consider whether the engine has enough volume from the pump to support the additional scavenging.
Not to mention if the loss of oil from it priming (read: purging air) would be enough to starve it during a filter change. Air does flow differently through the orifice (even one this small) than the more viscous oil...and when talking a pump volume as small as we are...path of least resistance.
In this application, I would personally revert to more frequent OCIs than attempting to apply an external filter.
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The .030 restrictor should put the brakes on too much volume being tapped off ..or so I would imagine. He can offset any air purging issues by prefilling (it should be an "hydraulic over air" situation. The air will be easier to move than the fully enveloped filter just due to the difference in mass being pushed ..but
)
This occurs with the big (thinking) CT500/750 filters from Luberfiner. They're REALLY BIG. If you're installing them on anything without a massive volume output, you have to restrict the inlet since they hold a few gallons of oil (5.5 for the 750 C/CT). Normally, the restriction is on the outlet.
This occurs with the big (thinking) CT500/750 filters from Luberfiner. They're REALLY BIG. If you're installing them on anything without a massive volume output, you have to restrict the inlet since they hold a few gallons of oil (5.5 for the 750 C/CT). Normally, the restriction is on the outlet.
Ummm, volume is relative...while that 0.030" orifice might be fine for a typical engine with a REAL oil pump, the volume that boat motor will be able to maintain will be SIGNIFICANTLY less than a typical car engine's oil pump.
And you CANNOT compare any automotive/truck engine to this boat motor...night and day.
And you CANNOT compare any automotive/truck engine to this boat motor...night and day.
dnewton3
Staff member
All the more reason I want to see it done!
I'm all for experimentation and the joy of the pursuit of knowledge.
But in this situation, I'd rather live vicariously through others. I see no value in this other than someone else's tough lesson learned. But it's like a train wreck; I just gotta look!
I'm all for experimentation and the joy of the pursuit of knowledge.
But in this situation, I'd rather live vicariously through others. I see no value in this other than someone else's tough lesson learned. But it's like a train wreck; I just gotta look!
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Quote:
Ummm, volume is relative
Indeed. Why just today I bought a large sized gallon of milk. Oddly, it was the exact same price as the compact sized gallon of milk. Whole milk too. None of that light small gallons in my 'frig. (j/k
)
Quote:
while that 0.030" orifice might be fine for a typical engine with a REAL oil pump
..and what type of oil pump does this engine have?
Quote:
the volume that boat motor will be able to maintain will be SIGNIFICANTLY less than a typical car engine's oil pump.
One would assume so .. if for no other reason than it's a much smaller engine. I'm sure that my HV oil pump on my 4.0 doesn't compare to some 8 liter diesel ..or even a 5.9 liter diesel.
I'm not really arguing with you, but you're stating a list of usual "fears" (BITOG is a well of anxiety of potential fears "If you do that, you'll be labeled a heretic by the office of blah-blah-blah) that are more or less assumptions of stuff that is unknown ("you'll shoot your eye out, kid").
There are very few ways to find out if this dog hunts. The engineer that designed it is probably retired or in another country.
That's the problem with exploring. There aren't all that many ways to get their from here if you're trail blazing. Heck, it's not like he's attempting to use 0w-10 oil in a pushrod/timing chain antiquated design engine. Sheesh ..someone would be a fool to risk something like that just for the sake of finding out if it works.
Ummm, volume is relative
Indeed. Why just today I bought a large sized gallon of milk. Oddly, it was the exact same price as the compact sized gallon of milk. Whole milk too. None of that light small gallons in my 'frig. (j/k
Quote:
while that 0.030" orifice might be fine for a typical engine with a REAL oil pump
..and what type of oil pump does this engine have?
Quote:
the volume that boat motor will be able to maintain will be SIGNIFICANTLY less than a typical car engine's oil pump.
One would assume so .. if for no other reason than it's a much smaller engine. I'm sure that my HV oil pump on my 4.0 doesn't compare to some 8 liter diesel ..or even a 5.9 liter diesel.
I'm not really arguing with you, but you're stating a list of usual "fears" (BITOG is a well of anxiety of potential fears "If you do that, you'll be labeled a heretic by the office of blah-blah-blah) that are more or less assumptions of stuff that is unknown ("you'll shoot your eye out, kid").
There are very few ways to find out if this dog hunts. The engineer that designed it is probably retired or in another country.
That's the problem with exploring. There aren't all that many ways to get their from here if you're trail blazing. Heck, it's not like he's attempting to use 0w-10 oil in a pushrod/timing chain antiquated design engine. Sheesh ..someone would be a fool to risk something like that just for the sake of finding out if it works.
My point was:
Volume as in gallons per minute versus ounces per minute...I like how you took that out of context.
If that engine is pushing a quart a minute through the engine, and you scavenge off a quart for the bypass; what lubes the engine?? Path of least resistance, through the filter and not through the engine where it is needed.
Further, while a bypass could be made to work, one spec'd for a car (and a car's oil pump volume)????
But what do I care...its not my $2k engine you guys want to have as a guinea pig...
Volume as in gallons per minute versus ounces per minute...I like how you took that out of context.
If that engine is pushing a quart a minute through the engine, and you scavenge off a quart for the bypass; what lubes the engine?? Path of least resistance, through the filter and not through the engine where it is needed.
Further, while a bypass could be made to work, one spec'd for a car (and a car's oil pump volume)????
But what do I care...its not my $2k engine you guys want to have as a guinea pig...
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Quote:
Volume as in gallons per minute versus ounces per minute.
How do we know this is so?
I'll wager that a smaller engine has a proportionally lesser flow ..but I don't know.
Quote:
.I like how you took that out of context.
No! It's not so! ( remember me? j/k
)
Quote:
If that engine is pushing a quart a minute through the engine, and you scavenge off a quart for the bypass; what lubes the engine??
If my aunt had slightly different anatomy ..she'd be my uncle
..but the answer is "nothing".
Quote:
Path of least resistance, through the filter and not through the engine where it is needed.
Again, what makes you assume this? How do we know this to be so
Relax, deeter .. I'm not really giving you a hard time. I just really have a static aversion to the reaction to stuff that no one has done before ..speculating as though it's a given that THE MOST DISASTROUS outcome is an assured result. The odds are equal that it will work out just fine.
If you look at some of XS650's postings on other boards, you'll see that there are plenty of people who tap in where the design engineers didn't see a point to do so.
If I didn't know better, I'd say that you're taking the Steve S "why in the world would you do something so idiotic" guide to finer posting (and even here, I'm j/k
)
Laugh
Volume as in gallons per minute versus ounces per minute.
How do we know this is so?
Quote:
.I like how you took that out of context.
No! It's not so! ( remember me? j/k
Quote:
If that engine is pushing a quart a minute through the engine, and you scavenge off a quart for the bypass; what lubes the engine??
If my aunt had slightly different anatomy ..she'd be my uncle
..but the answer is "nothing".
Quote:
Path of least resistance, through the filter and not through the engine where it is needed.
Again, what makes you assume this? How do we know this to be so
Relax, deeter .. I'm not really giving you a hard time. I just really have a static aversion to the reaction to stuff that no one has done before ..speculating as though it's a given that THE MOST DISASTROUS outcome is an assured result. The odds are equal that it will work out just fine.
If you look at some of XS650's postings on other boards, you'll see that there are plenty of people who tap in where the design engineers didn't see a point to do so.
If I didn't know better, I'd say that you're taking the Steve S "why in the world would you do something so idiotic" guide to finer posting (and even here, I'm j/k
Laugh
And I'm not saying don't do it...but a bypass, designed for a car, will most likely not work without modification to limit the flow.
dnewton3
Staff member
Hey, where'd the OP get off to in this whole discussion? Me thinks we left him in the dust somewhere ...
I'm still curious as to the use of the motor (what on, how often, and for how long), and the intended application/location of the BMK21 system? Or maybe he realized the silliness of the whole idea?
Some things are great to ponder, if even out loud, but not to be done in reality.
I'm still curious as to the use of the motor (what on, how often, and for how long), and the intended application/location of the BMK21 system? Or maybe he realized the silliness of the whole idea?
Some things are great to ponder, if even out loud, but not to be done in reality.
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Oh ..(said like RR in his debate with Jimmy Carter) "there you go again" ... clouding the discussion with pertinent details and essential information.
You're no fun anymore
You're no fun anymore
A nice stainless Frantz hanging off the side would sure be a conversation starter...
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