The water isn't during running, it's condensate during storage. The low operating temp may not get the oil hot enough to burn it off, especially if the basestock is prone to contain it, like some of group 5 's (or maybe even grp 4's that need grp 5 'additive' for seal conditioning?) Guessing but it's probably easier for the oems to make a blanket statement advising against them to try and identify which brands and labels are ok. Especially when formulations are subject to change, and the non synthetic products are more than adequate.
Why no synthetic oil for marine engines?
- Thread starter Johnny248
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Let me expose my ignorance.
While I've always been curious about the lower coolant temps (output level still doesn't flush with me = but), those who have used IR temp guns or real gauges don't report cold oil temps. I think the typical output level (WOT or near WOT) and lack of normal cooling (basically air flow over the pan) trumps that. I would see it being an issue with engines having forced circulation cooling for the oil.
Is forced circulation oil cooling common?
While I've always been curious about the lower coolant temps (output level still doesn't flush with me = but), those who have used IR temp guns or real gauges don't report cold oil temps. I think the typical output level (WOT or near WOT) and lack of normal cooling (basically air flow over the pan) trumps that. I would see it being an issue with engines having forced circulation cooling for the oil.
Is forced circulation oil cooling common?
I don't believe so. Some boats do have oil coolers on them, but I am pretty sure that they have raw water flowing through them. I have noticed though that if I am running the engine out of the water with muffs on it, the engine cooling temp never gets hot at all, but when I goto change the oil, it is definitely warm, so......
Originally Posted By: Volvohead
Originally Posted By: tig1
Why would a marine engine injest water into the engine any more than a car engine? So far I see no reason not to use synt oil in marine use.
Have you ever stood in a bilge? Have you ever been underway on the water? Do you know what raw water cooling is all about?
+1 Talk about a wet hostile environment!
Originally Posted By: tig1
Why would a marine engine injest water into the engine any more than a car engine? So far I see no reason not to use synt oil in marine use.
Have you ever stood in a bilge? Have you ever been underway on the water? Do you know what raw water cooling is all about?
+1 Talk about a wet hostile environment!
Originally Posted By: Pablo
I'll be blunt. What you say about synthetics not being tolerant of water and fuel is wrong. In reality it's the opposite.
Rather than put the rabbit in the hat by talking about "a well compounded synthetic marine oil", point out specifically what I've said in this thread that you disagree with.
Any synthetic that contains esters, either in base or as a carrier oil, is unstable in marine applications. Period. And that implicates quite a few synthetics. Perhaps even yours. All VIIs are a problem once you start dumping fuel and water into them at the extreme rates that marine inboards do (we're not talking about outboards here, and I think I was clear about that). I'm not going to argue over how and whether this happens. It does. High dilution is the essential nature of the beast. Anyone comparing marine conditions to that on land is delusional. Some of the more interesting comments above are from land yachtsmen.
And I doubt that any synthetic anti-corrosion package is significantly better than that in a premium HDEO such as Rotella or Delo.
I'm certain that VP specifies an ester-free formula. It may also contain very little or no VIIs. That's my idea of a well compounded marine synthetic. If your oils don't contain complex VIIs and esters, great. Otherwise, I stand by my comments.
No lubricant protects an engine against a riser gasket failure. Raw sea water pours in through the exhaust valves and washes down the cylinders. Anyone thinking any oil saved his engine from damage is crazy.
And I'm not selling anything and don't profit whether someone uses an HDEO, Amsoil, or baby oil in their engines.
I'll be blunt. What you say about synthetics not being tolerant of water and fuel is wrong. In reality it's the opposite.
Rather than put the rabbit in the hat by talking about "a well compounded synthetic marine oil", point out specifically what I've said in this thread that you disagree with.
Any synthetic that contains esters, either in base or as a carrier oil, is unstable in marine applications. Period. And that implicates quite a few synthetics. Perhaps even yours. All VIIs are a problem once you start dumping fuel and water into them at the extreme rates that marine inboards do (we're not talking about outboards here, and I think I was clear about that). I'm not going to argue over how and whether this happens. It does. High dilution is the essential nature of the beast. Anyone comparing marine conditions to that on land is delusional. Some of the more interesting comments above are from land yachtsmen.
And I doubt that any synthetic anti-corrosion package is significantly better than that in a premium HDEO such as Rotella or Delo.
I'm certain that VP specifies an ester-free formula. It may also contain very little or no VIIs. That's my idea of a well compounded marine synthetic. If your oils don't contain complex VIIs and esters, great. Otherwise, I stand by my comments.
No lubricant protects an engine against a riser gasket failure. Raw sea water pours in through the exhaust valves and washes down the cylinders. Anyone thinking any oil saved his engine from damage is crazy.
And I'm not selling anything and don't profit whether someone uses an HDEO, Amsoil, or baby oil in their engines.
All esters aren't "unstable" in wet environments, however most are water soluble and some can and do present problems in wet environments. Remember - esters are a huge number of organic compounds. Your general statements are what get you on squishy ground. I say ""a well compounded synthetic marine oil" to only exemplify that your rules that you expound, (for whatever reason), have exceptions.
I can say without a doubt there are synthetic marine oils with anti-corrosion packages that are FAR superior to OTS OTR HDEO's.
You asked me some questions, so I answered them. I never said it's not wet in the bilge of a boat, nor did I say any oil will protect an engine with a major intake failure. You seem to want call people "delusional" and "crazy". I refrain from that kind of junk and just say that you are not an expert in all marine lubrication matters, regardless of your tone.
I can say without a doubt there are synthetic marine oils with anti-corrosion packages that are FAR superior to OTS OTR HDEO's.
You asked me some questions, so I answered them. I never said it's not wet in the bilge of a boat, nor did I say any oil will protect an engine with a major intake failure. You seem to want call people "delusional" and "crazy". I refrain from that kind of junk and just say that you are not an expert in all marine lubrication matters, regardless of your tone.
Originally Posted By: Pablo
You seem to want call people "delusional" and "crazy".
No, just those two. Most folks here are fairly sensible and reasonable minds are always free to differ.
If we all agreed all the time, what would there be to talk about?
You seem to want call people "delusional" and "crazy".
No, just those two. Most folks here are fairly sensible and reasonable minds are always free to differ.
If we all agreed all the time, what would there be to talk about?
so I guess how to do know if your synthetic oil contains esters or not?
Originally Posted By: Jdblya
so I guess how to do know if your synthetic oil contains esters or not?
The safest thing to do is use an oil/synthetic oil that is marine rated by the manufacturer.
so I guess how to do know if your synthetic oil contains esters or not?
The safest thing to do is use an oil/synthetic oil that is marine rated by the manufacturer.
Originally Posted By: Volvohead
Originally Posted By: Pablo
You seem to want call people "delusional" and "crazy".
No, just those two. Most folks here are fairly sensible and reasonable minds are always free to differ.
If we all agreed all the time, what would there be to talk about?
True enough!
Originally Posted By: Pablo
You seem to want call people "delusional" and "crazy".
No, just those two. Most folks here are fairly sensible and reasonable minds are always free to differ.
If we all agreed all the time, what would there be to talk about?
True enough!
Originally Posted By: Jdblya
so I guess how to do know if your synthetic oil contains esters or not?
That's what it comes down to. That, and how much and the quality of the VIIs used by the blender. And whether your particular marine engine will benefit from a synthetic in a meaningful way, considering the factors.
There are some good full synthetic marine oils available. The manufacturers are finally starting to get into it, as it's a good profit center. Goodness knows why else . . . maybe they've cheapened some internals on the new stuff. A good marine blender should avoid the problematic components that are more prevalent in automotive oils. Whether it is genuinely necessary to run a marine synthetic is up to each boater and warranty.
Where I strongly caution is on the use of automotive synthetics in marine applications. Pablo's comment that some esters aren't unstable - but many are water soluble - fairly speaks to the risks. Similar risks arise with VIIs.
But most marine engines hold up extremely well on HDEOs and have done so for decades. It's a proven, safe option where the consequences can be very expensive. Marinized engines are big ticket items. I think that for 95% of recreational boaters, a marine synthetic isn't needed for other than competition or warranty - including your 15 season old Ford 5.0. Again, we are talking about inboards here. Outboards are very different animals.
Everyone is free to use whatever they want. It's their boat and their repair bill. I just try to share my personal experience going back a long time, and that of family members that have owned working marinas for decades.
so I guess how to do know if your synthetic oil contains esters or not?
That's what it comes down to. That, and how much and the quality of the VIIs used by the blender. And whether your particular marine engine will benefit from a synthetic in a meaningful way, considering the factors.
There are some good full synthetic marine oils available. The manufacturers are finally starting to get into it, as it's a good profit center. Goodness knows why else . . . maybe they've cheapened some internals on the new stuff. A good marine blender should avoid the problematic components that are more prevalent in automotive oils. Whether it is genuinely necessary to run a marine synthetic is up to each boater and warranty.
Where I strongly caution is on the use of automotive synthetics in marine applications. Pablo's comment that some esters aren't unstable - but many are water soluble - fairly speaks to the risks. Similar risks arise with VIIs.
But most marine engines hold up extremely well on HDEOs and have done so for decades. It's a proven, safe option where the consequences can be very expensive. Marinized engines are big ticket items. I think that for 95% of recreational boaters, a marine synthetic isn't needed for other than competition or warranty - including your 15 season old Ford 5.0. Again, we are talking about inboards here. Outboards are very different animals.
Everyone is free to use whatever they want. It's their boat and their repair bill. I just try to share my personal experience going back a long time, and that of family members that have owned working marinas for decades.
So I emailed Amsoil tech support to ask them if amsoil has done something to address this inboard conditions of fuel dilution etc, and this is what I received back.
Thank you for contacting AMSOIL.
In response to your inquiry,
We have received no claims of moisture in the oil for inboard applications. We are certainly aware of there being issues with moisture in fuel.
Sincerely,
xxxxxx
So, I wrote back. I'm not sure if this guy did not understand my question, or what but he clearly did not answer the question at all =)
Thank you for contacting AMSOIL.
In response to your inquiry,
We have received no claims of moisture in the oil for inboard applications. We are certainly aware of there being issues with moisture in fuel.
Sincerely,
xxxxxx
So, I wrote back. I'm not sure if this guy did not understand my question, or what but he clearly did not answer the question at all =)
Originally Posted By: Pablo
All esters aren't "unstable" in wet environments, however most are water soluble and some can and do present problems in wet environments. Remember - esters are a huge number of organic compounds. Your general statements are what get you on squishy ground. I say ""a well compounded synthetic marine oil" to only exemplify that your rules that you expound, (for whatever reason), have exceptions.
I can say without a doubt there are synthetic marine oils with anti-corrosion packages that are FAR superior to OTS OTR HDEO's.
You asked me some questions, so I answered them. I never said it's not wet in the bilge of a boat, nor did I say any oil will protect an engine with a major intake failure. You seem to want call people "delusional" and "crazy". I refrain from that kind of junk and just say that you are not an expert in all marine lubrication matters, regardless of your tone.
I like motorcycle synthetics Like Amsoil 20W-50....tested for long term storage and great anti-corrosion properties. I know what I need and what works.
All esters aren't "unstable" in wet environments, however most are water soluble and some can and do present problems in wet environments. Remember - esters are a huge number of organic compounds. Your general statements are what get you on squishy ground. I say ""a well compounded synthetic marine oil" to only exemplify that your rules that you expound, (for whatever reason), have exceptions.
I can say without a doubt there are synthetic marine oils with anti-corrosion packages that are FAR superior to OTS OTR HDEO's.
You asked me some questions, so I answered them. I never said it's not wet in the bilge of a boat, nor did I say any oil will protect an engine with a major intake failure. You seem to want call people "delusional" and "crazy". I refrain from that kind of junk and just say that you are not an expert in all marine lubrication matters, regardless of your tone.
I like motorcycle synthetics Like Amsoil 20W-50....tested for long term storage and great anti-corrosion properties. I know what I need and what works.
Theres no reason not to use synthetics in marine engines. In fact I am not a huge synthetics fan, but if there is one place they would excell it would be Marine use. These engine are always under load, so better film strenght will help. Also, although marine engine coolant runs cooler than auto, the oil temp runs hotter. That means cheap oils will shear down fast, advantage to synthetic. Marine oil changes can be expensive, so the long drain intervale should help those who put on a lot of hours in a season.
As for why there are not widely recommened, the manufactures have a good gig selling there own proprietary oils, and would lose that market with an endorsement of synthestics. It will come as soon as they can get the money to flow there way...
As for why there are not widely recommened, the manufactures have a good gig selling there own proprietary oils, and would lose that market with an endorsement of synthestics. It will come as soon as they can get the money to flow there way...
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one of the best reasons to use a 'purpose-built' synth in a marine app would be the excellent storage properties.
This is of supreme importance in 2 strokes. Bottom end bearings rust easily if not well protected. I am certain that no reg dino can match the proper synth in protecting these long term.
And no one who uses them can dispute the claim about the synth protecting your motor. Huge quantities of water can run through your motor without harm with a synth. Miscible isn't always a bad word!
No amount of old outdated info will keep me from using all synthetic marine products in my boats, jet skis, and everything else. They are simply superior, and especially so when the going gets tough.
This is of supreme importance in 2 strokes. Bottom end bearings rust easily if not well protected. I am certain that no reg dino can match the proper synth in protecting these long term.
And no one who uses them can dispute the claim about the synth protecting your motor. Huge quantities of water can run through your motor without harm with a synth. Miscible isn't always a bad word!
No amount of old outdated info will keep me from using all synthetic marine products in my boats, jet skis, and everything else. They are simply superior, and especially so when the going gets tough.
Hi all and thanks for an interesting discussion,
From what I have learned from some Motul information (oil analysis and Material Data sheets) is that their "double-esters" (300V series) have great protection against fuel dilution, and they are apparently also water insoluble.
I am currently testing a 50/50 mix of their 10W40 and 15W50 in my VP 5.7GXI-F. The 10W40 seem to have good anti-corrosion, anti-acid and anti-foaming additives and the 15W50 has excellent protection against fuel dilution. I have had great experience with these oils in the past in high performance car engines, very little or no wear, reduced oil temperatures and increased performance (not much but measurable).
I can see that there are some reservations against esters, would you suspect that the Motul 300V would exhibit the same flaws?
If I have the opportunity, I will try to submit an UOA after this season.
Best Regards,
Johan
From what I have learned from some Motul information (oil analysis and Material Data sheets) is that their "double-esters" (300V series) have great protection against fuel dilution, and they are apparently also water insoluble.
I am currently testing a 50/50 mix of their 10W40 and 15W50 in my VP 5.7GXI-F. The 10W40 seem to have good anti-corrosion, anti-acid and anti-foaming additives and the 15W50 has excellent protection against fuel dilution. I have had great experience with these oils in the past in high performance car engines, very little or no wear, reduced oil temperatures and increased performance (not much but measurable).
I can see that there are some reservations against esters, would you suspect that the Motul 300V would exhibit the same flaws?
If I have the opportunity, I will try to submit an UOA after this season.
Best Regards,
Johan
Mercury Marine/MercCruiser has a full synthetic oil available and recommended.
Volvo-Penta also recommends synthetic oil.
So the question boils down to whos oil, which oil and how much$$.
Volvo-Penta also recommends synthetic oil.
So the question boils down to whos oil, which oil and how much$$.
I ran a syn blend 15w40 in a 2.5 4 cyl merc cruiser, that little motor was as smooth as a sewing machine at 3600 to 3800 rpm. Never ever any oil issues running this oil. i did once a year changes at the end of every season, and i hated every [censored] oil change i did on this boat, i didn't like the idea of pumping the oil through the dip stick tube and it was a real [censored] to get a pan down under the engine and impossible to get out without spilling oil. So i made a pan with a hose connected to it ran the hose out the back drain hole, this was a slow process but it worked, and the back of boat was never a oily grease pit.
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