I had a '68 slickcraft with a 250 chevy 6 cyl motor.I used 5 qts of pennsoil 30 or 40 wt reg car oil in it, with a std purolater filter.I used that combo because the original owner used it.Never had any oil issues. boat was in salt water it's whole life.I had a cyl head that cracked, and the exhaust manifold got porous. I used to run it at between 3000-3200 rpms most of the time. I changed the oil at the end of the season.it would cost less then $20 to do the oil change.That would be my reason for not using synthetic oil in a marine engine. The boat has been sold and I don't know if it's still running, but I bought it when it was 30 years old and had it 6 years. I figure I put between 50 -70 hours a season on it.it was a tough motor.,,
Why no synthetic oil for marine engines?
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Bluestream: "although marine engine coolant runs cooler than auto, the oil temp runs hotter."
Hmmm ... care to explain? I'd think the coolant would get (proportionately) as hot as the engine oil. Are you talking about the water brought in, cycled one then shot back out? If that's the case, it's completely understandable.
SteveSRT8: "one of the best reasons to use a 'purpose-built' synth in a marine app would be the excellent storage properties."
While some synthetic base oils may have a slightly better affinity for metal than mineral oils, I think the corrosion protection in a lubricant comes primarily from the additive package ... with marine and HDEO oils having a significant advantage in this area.
As Pablo points out, any respectable blender would use a water-resistant ester when formulating a synthetic marine oil.
So, I believe the recommendation to avoid synthetics is a CYA move by the manufacturers. This kind of statement is common in equipment manufacturers as providing for all "ifs" and "buts" for various oils and fuel additives would be too complicated ... and oil and additive formulations can change in just a few months time.
Hmmm ... care to explain? I'd think the coolant would get (proportionately) as hot as the engine oil. Are you talking about the water brought in, cycled one then shot back out? If that's the case, it's completely understandable.
SteveSRT8: "one of the best reasons to use a 'purpose-built' synth in a marine app would be the excellent storage properties."
While some synthetic base oils may have a slightly better affinity for metal than mineral oils, I think the corrosion protection in a lubricant comes primarily from the additive package ... with marine and HDEO oils having a significant advantage in this area.
As Pablo points out, any respectable blender would use a water-resistant ester when formulating a synthetic marine oil.
So, I believe the recommendation to avoid synthetics is a CYA move by the manufacturers. This kind of statement is common in equipment manufacturers as providing for all "ifs" and "buts" for various oils and fuel additives would be too complicated ... and oil and additive formulations can change in just a few months time.
Bror Jace,in the two boats I have owned the one above the '68 Slickcraft, and a '71 Silverton both were run on regular oils and had original motors.The Silverton had a 318 chrysler fwc. It had a 180 degree thermostat and the Slickcraft had a 6 cyl chevy raw water cooled. It had a 160 degree thermostat. I had a head gasket on the 318 blow and had anti freeze in the oil. the same thing would have happened with synthetic oil. That requires a flush and refill after the gasket repair.Synthetic oil would cost more to change so no benefit is to be had.And with the '68 the old parts on the motor were starting to go but had nothing to do with the oil. As I said in the other post, the '68 was 30 years old with the original motor when I bought it never used oil between changes and was 36 years old when I sold it on regular 40 weight oil.the '71 was also the original motor with 550 hrs on it when I bought it and had 900hrs when I sold it 5 yrs later, using straight 30 wt regular Valvoline oil. these boats were used in salt water for fishing and were regularly run between 3000- 3200 rpms.their oil changed at the end of the season for winter storage. Based on my experience there would be no reason to use more costly synthetic oils, when you can get extreme longevity from the cheaper mineral oils.
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Sorry BigCahuna, you got me all wrong. I'm not a big fan of synthetics in marine (or OPE) applications for the reasons of moisture contamination, fuel dilution, long storage times, etc ...
I was merely going back to the original topic ... why would a manufacturer recommend synthetics NOT be used? While I'm not a fan, I think this is just another good example of nonsensical recommendations from manufacturers that don't need to be followed if you know what you're doing and use quality products and reasonable maintenance schedules.
So, if a big Amsoil fan wants to run their marine synthetic oil, I think they will get great results ... but probably no better than Pennzoil Marine or conventional Chevron Delo 400 ... or their new Delo 400 20W-40 Marine:
http://www.marketwatch.com/story/chevron...mind-2009-09-21
With OPE the bass-ackwardness was recommending straight 30 weights for decades longer than they needed to. Same with non-detergent oils (although those two are slowly changing). With marine engines, it's synthetic oil ... same with the Nissan I owned a few years ago ... and the recommendation against fuel adds by just about every manufacturer. These are examples of dumbed-down CYA recommendations for the most part. A thoughtful person, say someone who has been on this site for a while, can do better.
I was merely going back to the original topic ... why would a manufacturer recommend synthetics NOT be used? While I'm not a fan, I think this is just another good example of nonsensical recommendations from manufacturers that don't need to be followed if you know what you're doing and use quality products and reasonable maintenance schedules.
So, if a big Amsoil fan wants to run their marine synthetic oil, I think they will get great results ... but probably no better than Pennzoil Marine or conventional Chevron Delo 400 ... or their new Delo 400 20W-40 Marine:
http://www.marketwatch.com/story/chevron...mind-2009-09-21
With OPE the bass-ackwardness was recommending straight 30 weights for decades longer than they needed to. Same with non-detergent oils (although those two are slowly changing). With marine engines, it's synthetic oil ... same with the Nissan I owned a few years ago ... and the recommendation against fuel adds by just about every manufacturer. These are examples of dumbed-down CYA recommendations for the most part. A thoughtful person, say someone who has been on this site for a while, can do better.
You had me all exited over the new Delo 20W-40. It looks like it is only for two specific large marine diesels.
https://www.cbest.chevron.com/generated/MSDS/PDS32799780.PDF
Ed
https://www.cbest.chevron.com/generated/MSDS/PDS32799780.PDF
Ed
Sorry Ed. Right after I posted the above I went on a search for more specifics on the Delo 710 LE 20W-40 ... but only found about a dozen versions of the same (recent) press release.
When I scoured them, I found out that it is for a very specific type of marine diesel engine.
Funny that the link to the Delo Performance website still has no information on this new engine lube. What a lousy way to market a product.
Another odd thing ... it says this new oil has no zinc!
When I scoured them, I found out that it is for a very specific type of marine diesel engine.
Funny that the link to the Delo Performance website still has no information on this new engine lube. What a lousy way to market a product.
Another odd thing ... it says this new oil has no zinc!
I saw that on their site before. I was not able to find out if they say it is backward compatible or not?
Originally Posted By: Johnny248
Originally Posted By: Volvohead
Originally Posted By: Jdblya
Yet Mercruiser says use 5w40 oil in their engines. And again, why would the recommend not using synthetic oils?
Where does Mercury Marine say THAT? I haven't seen their latest I/O service books, but last I checked they specified their 25w-40 or a straight 30 for their inboards.
The reason Mercury, and many very experienced boaters, don't use synthetics or wide multivis oils in other than newer outboards is that most of the time, you don't need what a synthetic offers, and you don't want a lot of VIIs around. The synthetic oil salespeople may not like to hear that. But that's the truth.
FWIW, synthetics have been around since the early 70s, and there were a few trying them on the water even then, with mixed results. Most of us run conventional HDEOs or racing blends, and enjoy gas engine lives of many thousands of hours. These engines run cold, wet and rich. Perhaps in a competition environment or with newbies you'll see full synthetics. Or in a newer outboard or Volvo still under warranty. But that's about it.
But if I were you, I wouldn't be focusing on what wide viscosity synthetic oil to use in that Ford 5 liter. I'd be getting compression and leakdown tests and setting aside some repair funds after pumping water for that long. A blown riser gasket is usually very bad news. I'm very surprised you didn't hydrolock it outright.
BTW, VP doesn't belong in the same bucket as OMC. The former is a cut above both OMC and Mercury in the I/O hierarchy.
I don't know why I said 5w40, I meant 25w40. What does VIIs mean? Are you saying that a synthetic oil would be worse ina cold wet and rich enviroment than a conventional oil? or just that a synthetic would not give you any benifets. And what about the wear protection of a synthetic over the conventional? Finally, I would think an oil that is NMMA FC-W approved would meet marine manufacturers specs for anti-rust and water saturation?
I also Ran compression test, twice. Everything looks good. The problem is that I don't know exactly how long I was running the engine with the water in it. All I know is that it was in there.
If you are going to have problems from water in the oil "like you had" will be a bearing and cam problem.
Originally Posted By: Volvohead
Originally Posted By: Jdblya
Yet Mercruiser says use 5w40 oil in their engines. And again, why would the recommend not using synthetic oils?
Where does Mercury Marine say THAT? I haven't seen their latest I/O service books, but last I checked they specified their 25w-40 or a straight 30 for their inboards.
The reason Mercury, and many very experienced boaters, don't use synthetics or wide multivis oils in other than newer outboards is that most of the time, you don't need what a synthetic offers, and you don't want a lot of VIIs around. The synthetic oil salespeople may not like to hear that. But that's the truth.
FWIW, synthetics have been around since the early 70s, and there were a few trying them on the water even then, with mixed results. Most of us run conventional HDEOs or racing blends, and enjoy gas engine lives of many thousands of hours. These engines run cold, wet and rich. Perhaps in a competition environment or with newbies you'll see full synthetics. Or in a newer outboard or Volvo still under warranty. But that's about it.
But if I were you, I wouldn't be focusing on what wide viscosity synthetic oil to use in that Ford 5 liter. I'd be getting compression and leakdown tests and setting aside some repair funds after pumping water for that long. A blown riser gasket is usually very bad news. I'm very surprised you didn't hydrolock it outright.
BTW, VP doesn't belong in the same bucket as OMC. The former is a cut above both OMC and Mercury in the I/O hierarchy.
I don't know why I said 5w40, I meant 25w40. What does VIIs mean? Are you saying that a synthetic oil would be worse ina cold wet and rich enviroment than a conventional oil? or just that a synthetic would not give you any benifets. And what about the wear protection of a synthetic over the conventional? Finally, I would think an oil that is NMMA FC-W approved would meet marine manufacturers specs for anti-rust and water saturation?
I also Ran compression test, twice. Everything looks good. The problem is that I don't know exactly how long I was running the engine with the water in it. All I know is that it was in there.
If you are going to have problems from water in the oil "like you had" will be a bearing and cam problem.
No marine synthetics?
http://www.exxonmobil.com/UK-English/Marine/PDS/GLXXENMRNEMMobil_Delvac_1_SHC_5W-40.asp
Charlie
http://www.exxonmobil.com/UK-English/Marine/PDS/GLXXENMRNEMMobil_Delvac_1_SHC_5W-40.asp
Charlie
UG Passat, thanks for posting that pic.
Interesting that they would label a full synthetic as a straight 30 weight when its pour point probably qualifies it as a 10W-30 or 5W-30 ... maybe even 0W-30.
I think it just goes to illustrate the games that are played with oil labels and recommendations because of the oil culture. Obviously, a lot of manufacturers still recommend straight weights and many veteran boaters and marine mechanics continue to swear by the stuff.
Still, things like this just muddy the waters. I wish an unbiased 3rd party (SAE?) certified the weights so we're comparing apples to apples all the time ... all the while dispelling long held myths.
Interesting that they would label a full synthetic as a straight 30 weight when its pour point probably qualifies it as a 10W-30 or 5W-30 ... maybe even 0W-30.
I think it just goes to illustrate the games that are played with oil labels and recommendations because of the oil culture. Obviously, a lot of manufacturers still recommend straight weights and many veteran boaters and marine mechanics continue to swear by the stuff.
Still, things like this just muddy the waters. I wish an unbiased 3rd party (SAE?) certified the weights so we're comparing apples to apples all the time ... all the while dispelling long held myths.
I know the guys on Offshoreonly.com use a lot of 20W-50 M-1 v-twin and Amsoil as well.
V-Twin has both corrosion inhibitors and a lot of ZDDP. Engines look great on routine teardown. We are talking about engine that are between 500 HP - 1000+ HP costing megabucks. Oil price is not a bigggie here.
Amsoil Racing team did very well this year...they run Amsoil by the way.
V-Twin has both corrosion inhibitors and a lot of ZDDP. Engines look great on routine teardown. We are talking about engine that are between 500 HP - 1000+ HP costing megabucks. Oil price is not a bigggie here.
Amsoil Racing team did very well this year...they run Amsoil by the way.
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Originally Posted By: NHHEMI
90% of my outboard( Mercury 40HP 4-stroke )use is from October to February during waterfowl season. Condensation is a big cocnern of mine. Running in the summer you heat the engine up enough to burn it off. In the middle of January that water can be 28-30 degrees( saltwater use - freezes at a lower temp than fresh )which does not help your condensation issue.
I am trying the Amsoil 10W-30 4-stroke oil for the 1st time. I actually want it for the improved cold temperature flow. I change the oil once every year. Actually, the deal Pablo got me on the oil is about what I pay for the Mercury 10W-30 oil. Hopefully it will do well under the extreme conditions I use my motor in?
Update on my earlier post( I am being honest and unbiased with my review )...
I have put the boat away for the winter. Due to the loss of my 13 1/2 year old Lab, Thunder, in August and then getting a new pup in late Nov I did not get to run the boat as much this year. The desire to head out during waterfowl season was pretty low with the loss of my bud Thunder. I did go some however.
As hoped for the Amsoil did help with cold start( easier turn over and quieter engine while cold ). I think however I may go back to conventional oil at least during the late waterfowl season. Not that the Amsoil failed at anything it just is a case of it taking the engine significantly longer to come to full temp.
I think their product, due to the reduced friction, is better suited to warmer temps and water. I may run it during the summer and then up through the 1st half of waterfowl season( ends last week of Oct ). For the 2nd half and late goose( Nov - Feb )I will probably go back to conventional oil. Cost is the same +/- so it won't kill me draining the Amsoil out.
Overall pleased with the Amsoil.
90% of my outboard( Mercury 40HP 4-stroke )use is from October to February during waterfowl season. Condensation is a big cocnern of mine. Running in the summer you heat the engine up enough to burn it off. In the middle of January that water can be 28-30 degrees( saltwater use - freezes at a lower temp than fresh )which does not help your condensation issue.
I am trying the Amsoil 10W-30 4-stroke oil for the 1st time. I actually want it for the improved cold temperature flow. I change the oil once every year. Actually, the deal Pablo got me on the oil is about what I pay for the Mercury 10W-30 oil. Hopefully it will do well under the extreme conditions I use my motor in?
Update on my earlier post( I am being honest and unbiased with my review )...
I have put the boat away for the winter. Due to the loss of my 13 1/2 year old Lab, Thunder, in August and then getting a new pup in late Nov I did not get to run the boat as much this year. The desire to head out during waterfowl season was pretty low with the loss of my bud Thunder. I did go some however.
As hoped for the Amsoil did help with cold start( easier turn over and quieter engine while cold ). I think however I may go back to conventional oil at least during the late waterfowl season. Not that the Amsoil failed at anything it just is a case of it taking the engine significantly longer to come to full temp.
I think their product, due to the reduced friction, is better suited to warmer temps and water. I may run it during the summer and then up through the 1st half of waterfowl season( ends last week of Oct ). For the 2nd half and late goose( Nov - Feb )I will probably go back to conventional oil. Cost is the same +/- so it won't kill me draining the Amsoil out.
Overall pleased with the Amsoil.
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