synthetic oil

roffey

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I am going to change my oil to synthetic oil. What is the process? do I get cheep synthetic oil, if there is such a thing, run the motor for a bit, minutes on the cheep stuff and then change the oil and filter and put the good stuff in? Or should I just do a normal oil change?
 

GA_Boater

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Just do a normal oil change. The wee bit of remaining dino residue will mix and drain out in the next oil change.
 

rallyart

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There is no issue with synthetic and regular oils mixing. You just do a normal change. The 'flush' idea is an up sell from some oil service companies and, at best, just wastes your extra money.
 

JoLin

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'Semi-synthetic' oil is just a mix of synthetic and dino anyway, The 2 get along fine together. No worries.
 

Patfromny

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'Semi-synthetic' oil is just a mix of synthetic and dino anyway, The 2 get along fine together. No worries.
Then why do they tell you you can't go back to normal after a synthetic? I am just curious joLin. I have been a shade tree mechanic since I was 13 and have always heard you can't go back to normal after the switch. Just an old wives tale? It's one of those statements I always heard but never investigated because I never used synthetic. BTW, I just bought a Stihl chain saw and they extended the warranty just by me using their synthetic 2 stroke oil. They sold it cheap enough right where I bought the saw so I went for it.
 

oldjeep

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Who is "they"? The people selling the overpriced oil? Unless your engine calls for it, save your $ and use the recommended grade of conventional oil.
 

82rude

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Got the same deal Patfromny.,seeing as we need the oil anyways why not?Mine was a weedwacker.Not being able to go back to dino oil is an old wives tale that wont die,with one exception.There was an oil back in the day that was black or some such color and supposedly once you used it you were basically stuck with it though I cant remember the name or reason anymore.It sort of like the old wives tale of if I use premium in my 87 octane car it runs better.Its been proven time and time again as false but people still insist their car runs better.I imagine the 6 pack of oil I bought from sthil will last years as the wacker uses next to zero gas per use.
 

roffey

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Who is "they"? The people selling the overpriced oil? Unless your engine calls for it, save your $ and use the recommended grade of conventional oil.

This is interesting, I was under the impression that synthetic oils was just better. Like most here this boat is my baby and I will spend the extra money to do what is best for it.

So the question is synthetic oil better? Who here uses it? My boat is new and I thought now is the time to switch, maybe not?
 

Scott Danforth

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unless your motor calls for synthetic, it doesnt need it.
 

JoLin

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This is interesting, I was under the impression that synthetic oils was just better. Like most here this boat is my baby and I will spend the extra money to do what is best for it.

So the question is synthetic oil better? Who here uses it? My boat is new and I thought now is the time to switch, maybe not?

When I was young I used synthetics often. As time went on I realized that it's regular oil changes that make the difference, not whether it's dino or synthetic. If Stihl extended your warranty it has to do with that engine being a small, high revving, air-cooled 2 stroke. That's one instance when synthetic has an advantage, as it does burn cleaner in a gas-oil mix. I found that synthetic was less smokey than dino in my old 175hp Johnson 2-stroke. I used Pennzoil semi-syn in that engine.

If you're talking about the oil in a 4-stroke engine, then I say again that regular changes with the right spec oil is what's important. I no longer use synthetic or syn-blend oil in those as I feel it's a waste of money.

My .02
 

joe009

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i put much less then a 100 hrs each yeat on boat and change oil every fall,synthetic would be a wast of money.i do use yamaha oil for my f150
 

hemi rt

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Most people that switch to synthetic do so for the longer times between oil changes, normal oil change is about every 3000 miles, synthetic is 10,000 miles. No real reason to switch from Dino oil. Synthetic does stay on surfaces a little longer helping prevent what is called a dry start but under normal conditions you will never have this happen. Just use Dino oil, a good filter and save some money. If you switch to synthetic do your home work on which brand is better than another. People are starting to shy away from Pennzol for a number of reasons and I'm not going to get into that here.
 

H20Rat

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Nobody mentioned a used oil analysis yet.. Without doing a oil analysis, ANY conversation of regular vs synth is worthless. Even if your mfg doesn't call for it, an engine might benefit from synthetic oil, but you will have no idea without the analysis being done. I've seen lots of engines that showed half as much wear metals in the results when running synthetic, and they didn't call for it. Same goes for your oil change interval, you might be able to extend it with synthetic, you might not, guessing doesn't work.

Hang out over at BITOG if you want to know more than you ever thought possible about oil.

I personally run synthetic in almost everything. The only exception I can think of is my lawn mowing tractors, they get straight 30w. They tend to burn oil if you use a multi-weight in them. All my vehicles though get synthetic, and I have done oil analysis on them.
 

SeaDooSam

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I put synthetic in our engine. I just have heard it works better that way. No idea if it is true. It isn't cheap clearance stuff either. It is good marine synthetic stuff.
 

superbenk

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There were issues years ago going from synthetic to dino that was due to how synthetic was absorbed by seals & then shrunk after switching back (or something). Not sure how true/accurate that was or if it's still an issue to worry about.

This page talks about it (page #2 of the series): http://auto.howstuffworks.com/switch-to-synthetic-oil1.htm

[FONT=&quot]Like many myths, this one is based in fact. Early synthetics were made of esters, which were harder on seals, especially those made of neoprene. However, synthetic oils have come a long way since the early 1970s, and they're much nicer to delicate seals. But while synthetic oil won't create a leak, it will find one. Its streamlined molecular structure has no mercy for cracked or otherwise marginal seals. The oil and its additives may even clean deposits from the engine, which is good -- unless those deposits are acting like spackle on questionable seals.[/FONT]

Seems like it was just an issue on early synthetics.
 

Patfromny

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I have heard the benifit of synthetic is that it is more slippery than dino. Thus making the engine run with less resistance ergo better gas mileage. I have also heard it doesn't scrub heat as well as dino. That is just what my buddy told me. He is a machinist and he ran synthetic in his race car. I put synthetic in my mother's car (she lives with us) because she puts about a thousand miles a month on her car and the oil changes were more expensive every three months than doing synthetic every six. Or at least it was close enough that it made sense to me.
Superbenk, I think that is what I remember. The seals would dry up. I guess it is time to reboot the brain on that one. I just found out on another thread that you can change sides with radials now. Boy have I been out of car building for awhile. Lol
 

frantically relaxing

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Synthetic oil is very good at-- well, I don't know the official description, but lets say ' breaking surface tension'... as in, how you can fill a glass more than full of water, and the water will 'hang on' above the rim due to surface tension. Regular oil has more surface tension than synthetic, I believe due to molecular structure... What this means is, synthetic oil may find it's way past an old, aging gasket or seal that may adequately keep dino oil sealed up.

A few years ago I put some 20-50 synthetic in my old '76 Sportster. The poor thing sounded like I'd replaced the oil with chocolate milk. Regular 20-50 would build up 15psi of pressure when cold and 2-4psi when hot (which is normal). On a cold start the synthetic never budged the oil gauge. And, it leaked past my primary cover gasket...

Synthetic may be the bomb for some things, but I won't bother with it unless a warrantee is at risk...
 

Patfromny

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You need some hylomar there frantic. Lol. I would agree that there are certain instances where traditional oil is the way to go. My mom's car is the only one I have synthetic in. If it ain't broke, don't fix it. Standard oil has worked for me for many years. Not a knock on those who use synthetic. Just my choice. Now the new car recommendations to change standard oil every 5 months or 5000 miles is something I will never do. Having seen the internals on many sludgy engines has me convinced that 3000 or 3 months is max. My wife's owners manual says 5 months 5000, not sure if anyone else has read this.
 
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