Synthetic for 3208

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Obx

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I have 1989 3208 TA's and use T4 15w40, does anyone use synthetic oil and if so had any problems with oil leaks or other?
 
You can use synthetic but it’s a waste of money. Synthetic is just standard oil that as been further refined. It’s purpose is to not break down when used in tight clearance applications like modern high performance engines. 3208’s like heavy duty motor oil. Shell T4 or Delco 400. You can use T5 or T6 but you won’t gain anything.
 
Full synthetic Rotella T6 15-40 diesel oil is roughly the same price as Delco 400. I switched to Rotella synthetic a few years ago. Decreased oil consumption. Give it a try.
 
I think the hazards of using synthetic lube oil in older engines is a thing of the past. Important engine seals would swell or shrink (can’t remember which. Call a Cat rep.

Delo 30wt. is probably recommended.
 
I've been using T6 for 10 years or so in a Cat 3306B. There is zero, as in no oil consumption. The lubricity of synthetic oil is greater than pure dino oil, and like the arguments against bypass filters, I've yet to hear a good argument against cleaner and more slippery oil. And with respect, pure synthetic oil is not just more refined petroleum oil.

www.machinerylubrication.com/synthetic-oil-31800
 
I think the hazards of using synthetic lube oil in older engines is a thing of the past. Important engine seals would swell or shrink (can’t remember which. Call a Cat rep.

Delo 30wt. is probably recommended.



Right. Synthetics are no longer an issue with seals.
I of course would use Schaeffer 700 (15-40).
Nice to see you here Willy /Eric! [emoji16]
 
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I've been using T6 for 10 years or so in a Cat 3306B. There is zero, as in no oil consumption. The lubricity of synthetic oil is greater than pure dino oil, and like the arguments against bypass filters, I've yet to hear a good argument against cleaner and more slippery oil. And with respect, pure synthetic oil is not just more refined petroleum oil.

www.machinerylubrication.com/synthetic-oil-31800

Carl
The attached article does point out one of the issues with synthetics, that it doesn't do well in long very cold winter lay ups. The reason being stratification of additives as opposed to using pure Dino with additives. The way around this is a springtime oil change for those cold weather lay ups when using synthetics. This of course negates the advantages of longer oil changes for those who leave there boats on the hard during a hard winter.

How Chevron and the major diesel manufacturers have dealt with using the best of two worlds (or marketing hype) is Isothyn Technolgy for DELO 400. I doubt though that the Seattle- Vancouver area is deemed a cold winter layup. I'm happy with DELO 400. During this season's cruise to AK we've not seen the need for any oil additions when starting out with fresh oil.

Given some engines propensity for heavy smoking until warmed up (older Lehmans or Hinos?) I'm curious as to whether full synthetics ease that issue.
 
I have a car w 303,000 miles on the clock.
And I “need” more slippery oil?
Can only see it as a plus but?

Seriously I’d be interested to know how much more slippery syn oil is?
 

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I've been using T6 for 10 years or so in a Cat 3306B. There is zero, as in no oil consumption. The lubricity of synthetic oil is greater than pure dino oil, and like the arguments against bypass filters, I've yet to hear a good argument against cleaner and more slippery oil. And with respect, pure synthetic oil is not just more refined petroleum oil.

www.machinerylubrication.com/synthetic-oil-31800

I have bypass oil filters on both mains (3208 NA) and both generators. Like you, I can't see an argument against them. I've always used full synthetics in all my vehicles. I've wanted to put synthetic in the 3208's, but have always been told not to because of how "thin" the synthetic oil is and that my engines would leak more oil. My engines are 1998's. Sounds like you don't have these issues with T6. Was there any more oil drips from your engines? I talked to a Cat dealer and they couldn't say one way or another about the use of synthetic oil in my engine.
 
Carl
The attached article does point out one of the issues with synthetics, that it doesn't do well in long very cold winter lay ups. The reason being stratification of additives as opposed to using pure Dino with additives. The way around this is a springtime oil change for those cold weather lay ups when using synthetics. This of course negates the advantages of longer oil changes for those who leave there boats on the hard during a hard winter.

How Chevron and the major diesel manufacturers have dealt with using the best of two worlds (or marketing hype) is Isothyn Technolgy for DELO 400. I doubt though that the Seattle- Vancouver area is deemed a cold winter layup. I'm happy with DELO 400. During this season's cruise to AK we've not seen the need for any oil additions when starting out with fresh oil.

Given some engines propensity for heavy smoking until warmed up (older Lehmans or Hinos?) I'm curious as to whether full synthetics ease that issue.

Thanks Tom,

The link in my post discusses that, and like you, I assume Anacortes in the winter isn't what they're talking about for issues with additives. The same article mentions a figure of a 47% improvement in the performance of synthetic vs dino, and given what would be involved in swapping engines out in Delfin, I figure an additional $30 once a year for pure synthetic isn't a cost I'm worried about.
 
I have bypass oil filters on both mains (3208 NA) and both generators. Like you, I can't see an argument against them. I've always used full synthetics in all my vehicles. I've wanted to put synthetic in the 3208's, but have always been told not to because of how "thin" the synthetic oil is and that my engines would leak more oil. My engines are 1998's. Sounds like you don't have these issues with T6. Was there any more oil drips from your engines? I talked to a Cat dealer and they couldn't say one way or another about the use of synthetic oil in my engine.

I had some really minor leakage out the real seal, as in 3 tbs per year initially, but zero now. Not sure why, but that's what I observe.
 
I have a car w 303,000 miles on the clock.
And I “need” more slippery oil?
Can only see it as a plus but?

Seriously I’d be interested to know how much more slippery syn oil is?

Beats me. As I said, my perspective is that given the cost of problems with a $50k marine engine, I don't think the additional cost of synthetic is an argument against its usage, and I also don't think there is any argument to be made that synthetic is not a superior lubricant. So why not?
 
I have 1989 3208 TA's and use T4 15w40, does anyone use synthetic oil and if so had any problems with oil leaks or other?

As a lubricant expert I'd say it is very unlikely to have leaks related to Rotella T4. Shell uses GTL (Gas To Liquid) base stock which is quite a nice base stock to formulate with due to the high viscosity index. In the distant, and I mean distant, past early synthetics were associated with seal shrinkage. In those days only synthetic esters and polyalpholefins were available as synthetic base fluids. Frankly this problem was solved over 30 years ago and modern synthetics mainly use group III (high VI hydrocracked then isomerized) base oils. Keep in mind the term 'synthetic' is a marketing and not technical term. The historic technical definition of 'synthetic' encompasses essentially all modern base oils which are all hydrorcracked and isomerized.

By the way, the Cat 3208 will derive no real benefits from a synthetic. A good API CK4 or CJ4 oil is way more than this engine was ever designed to run on.
 
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Delfin wrote;
“ Beats me. As I said, my perspective is that given the cost of problems with a $50k marine engine, I don't think the additional cost of synthetic is an argument against its usage, and I also don't think there is any argument to be made that synthetic is not a superior lubricant. So why not?”

Would I be better off using synthetic less the cost? Sounds like a simple question and should command a simple answer.

But some people shoot rabbits w a 22. And there are some that use an 06 or a shotgun.

There is a good reason to use dino … your’e oil runs cleaner if changed frequently .. then dino oil would be more expensive. And to that end the by-pass would add to that. But who would need their oil to be as clean as it comes out of the bottle? Getting rid of almost all the abrasives in the oil would be a definite plus tho.

That little car in post #8 has a strong engine that sounds good in a throaty way during heavy throttle. Still use 10w30 oil. I’m the second owner and the first (a woman) drove her the first 270,000 miles. So she’s never been driven hard. Less side loading on the pistons and bores may lead to minimal wear .. opinion.
 
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Synthetic has its place. It is a requirement in my race car due to close tolerances. If I ran normal oil I would have wear issues and the life of my engine would be less. A lot less at hi RPMs. Synthetic is not more slippery and it’s not thinner, it is not some magic non petroleum artificial magic lubricant. It starts life as petroleum oil and is processed differently. Using it instead of normal oil is throwing away good money on a 3208 and most old school diesels. It is false logic to think you might get 30,000 hours out of your diesel instead of 20,000. It took my boat 30 years to get to 5,000 hours I doubt I will be alive when it hits 10,000.

Will it hurt to run synthetic? No.
 
The historic technical definition of 'synthetic' encompasses essentially all modern base oils which are all hydrorcracked and isomerized.

Slomo
Could you expand on this as to how a major brand differentiates between a synthetic Vs a standard oil? Also, what does Chevron's Isothyn designation for its DELO mean? Thanks
 
There’s so much “blend” out there I can see where the confusion is widespread.
I think if it says 100% synthetic on the bottle/jug how could it be legal to have dino oil in it?
If you don’t see 100% “synthetic” it must be a blend or 100% dino oil. In the 80’s there was numerous synthetic base stocks. But now if one was clearly superior (as in ticks all the boxes but “cheaper”) it could be the only base stock used in the bulk of synthetic oil production. And I can’t imagine there not being rather exotic base stocks being used for racing oil .. and sold OTC.

I still have a gallon of “100% synthetic” racing oil (Bell Ray brand) and it’s so viscous it will not work properly in oil injection systems like motorcycles and OB engines. It also dosn’t mix well in gasoline but is sold and used for motorcycle racing whereas they mix their fuel for each race. Well beyond the scope of general purpose lube oil.

In the 80’s (and probably now too) the most important feature of synthetic oil was it’s viscosity stability .. that is it’s ability to not thin out in extremely hot running conditions. It maintained it’s viscosity at higher temps than dino oil can. In a continuous climb out for 15 minutes in an UL aircraft running rich was necessary to keep the engine from seizing. Not so w synthetic. And there were other advantages.

But now there are probably fewer exotic synthetics. But I maintain that if it says “100% synthetic” there should be no dino oil in it.
 
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Tiltrider 1 wrote;
“Will it hurt to run synthetic? No”

I would tend to agree. But it could be problematic if one’s engine was not letter graded for it. Still it may be fine. But I would want to see the proper letter grade to feel guaranteed.
But if it is you’re good to go.
 
Cat engines and oil

Have a look at page 14/15 of this Cat document. I had a 3116 and this explains the reason Cat thinks you shouldn't use a multigrade. I do not know if it applies to your engine or not. CAT may do an updated document- worth looking for.

Gilbert
 

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Synthetic has its place. It is a requirement in my race car due to close tolerances. If I ran normal oil I would have wear issues and the life of my engine would be less. A lot less at hi RPMs. Synthetic is not more slippery and it’s not thinner, it is not some magic non petroleum artificial magic lubricant. It starts life as petroleum oil and is processed differently. Using it instead of normal oil is throwing away good money on a 3208 and most old school diesels. It is false logic to think you might get 30,000 hours out of your diesel instead of 20,000. It took my boat 30 years to get to 5,000 hours I doubt I will be alive when it hits 10,000.

Will it hurt to run synthetic? No.

Some might disagree. Regarding improved lubricity, countless studies have shown improved wear characteristics of synthetic oils over mineral oils. If that is not improved lubricity, let me know the correct word to use.

https://www.caranddriver.com/research/a32879214/synthetic-oil/

"The excellent oiliness (a lower coefficient of friction of one oil compared to another fluid of the same viscosity) of synthetic oils reduces engine wear during the initial, critical engine startup."

https://www.motortrend.com/how-to/truth-synthetics-way-just-extra-hp/
 
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Have a look at page 14/15 of this Cat document. I had a 3116 and this explains the reason Cat thinks you shouldn't use a multigrade. I do not know if it applies to your engine or not. CAT may do an updated document- worth looking for.

Gilbert

Cat does recommend multi grade oil, including synthetic, see page 8. The 3116 is a bit of a special case and for that motor, only single grade.
 
After researching opinions on engine oil for my 3208NA’s on marinediesel.com, the site Cat expert “dave” recommended using a single grade CG-4, for example Rotella T 30W, to reduce engine smoke and oil consumption.
The engines have always used Cat 15W-40 previously, but smoking on start up and using approximately 1 litre per 100 hours.

I’d be interested in hearing others opinions on this, and hope it’s not too far from thread discussions.
 
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On post #19 there’s quite a few mentions of single wt. oil.

And in post #20 “The excellent oiliness (a lower coefficient of friction of one oil compared to another fluid of the same viscosity) of synthetic oils reduces engine wear during the initial, critical engine startup."
That’s an assumption as many (mostly all) other oils also offer that feature. I think lubrication at start-up is mostly assured by a higher viscosity oil being used in the first place. I’ve never seen any real evidence of excessive wear during start-up. People are thinking based on a “sounds good” platform and the assumptions that follows.

Southern Boater,
I, we are in a minority on this one so do appreciate your input.
 
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I’ve never seen any real evidence of excessive wear during start-up.

Here you go...


https://www.machinerylubrication.com/Read/167/synthetic-gear-oil

www.researchgate.net/publication/286788628_Using_synthetic_basestocks_to_reduce_wear

https://forums.tdiclub.com/index.php?threads/diesel-engine-wear.18125/
 
Well, I use Royal Purple duralec 15w-40 in my Cummins 6BTa engines, and my generator.

Will it help anything??? I have no clue but I feel better about it. :blush:
 

Not clickable on my i-pad.
Can you tell me what percentage of reduction in drag and roughly under what conditions? I’ve always assumed it to be correct but to be meaningful the drag reduction would need to be (guessing) 5% or more. One percent would make it true but it woulldn’t have any value.

Strange but It’s clickable in a quote ..but not as posted.
I scanned the links. Reads like someone’s selling something and info. is lacking for operation under normal conditions and temps. All the info I saw was gathered (or was claimed to be) gathered while operating under extreme conditions.
I see that drag/friction is reduced but not in normal conditions.

I’ll stick by thinner oil drains off vertical surfaces much faster than thicker oil. And residual oil is the explanation that there is lubrication available at start-up. I had a two stroke (40hp twin) engine on an ultralight aircraft and when I took off the exhaust system and could see into the exhaust ports it looked like the pistons had paint brush marks on the vertical surface of the pistons. The only other theory was that the piston had been scored to the extreme. But the engine turned over freely.
It was obvious that it was a relatively heavy coating of oil (synthetic well over 50 weight) that had adhered to the piston. I could feel it w my fingers. Thick and slippery. Engine hadn’t been run for a week either.

So I’m thinking residual oil works very well and it’s the only thing that indicates it works is cars like my 87 Nissan w 304,000 miles on it using dino 10w30wt. it’s whole life .. except just straight 30w. It’s 2/3rds of a Nissan Z car engine (4cyl).
 
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Some might disagree. Regarding improved lubricity, countless studies have shown improved wear characteristics of synthetic oils over mineral oils. If that is not improved lubricity, let me know the correct word to use.

https://www.caranddriver.com/research/a32879214/synthetic-oil/

"The excellent oiliness (a lower coefficient of friction of one oil compared to another fluid of the same viscosity) of synthetic oils reduces engine wear during the initial, critical engine startup."

https://www.motortrend.com/how-to/truth-synthetics-way-just-extra-hp/

I'm sorry but "Car and Driver' or "Motor Trend' are not scientific resources. In fact in 35 years of lubricant development neither I or any other scientists I worked with ever referred to these publications for information of any type.
The proper source for studies on the relative performance of oils would be peer reviewed publications such as SAE (Society of Automotive Engineers), STLE (Society of Tribology and Lubrication Engineers), and similar sources. I won't bother with the technical details but suffice to say that a) almost all modern oils are 'synthetic' in that they use synthesized base oil b) almost all of the performance of oils is determined by the performance additive system and c) differences in 'wear' used for marketing claims are almost always based on tests which have little to no real world relevance. Very often these are bench scale tests designed for marketing purposes.
 
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Well, I use Royal Purple duralec 15w-40 in my Cummins 6BTa engines, and my generator.

Will it help anything??? I have no clue but I feel better about it. :blush:

If it makes you feel good then by all means keep doing it Kevin. No argument with feeling some love for your boat.:)

If you are doing it because you think your engine is going to live longer? That's a false economy. There is no real world proof that a 20,000 hour 3208 will become 30,000 hour engine if you run synthetic. Add to the fact that almost all of us will never see 10,000 hours on a 3208.

There is lots of proof that the wrong oil is superior to no oil.
 
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