kenmac said:
Come on now sound guy . 1st you say old , now you are saying antique . If your car / tractor leaks with stnethetic oil , it's because it lubricates better ie, getting into hard to reach places that your dino can't reach. This is why dino usually won't leak out of the seals & in some cases synethetic will . Synethetic has lubrication properties that dino can't match. funny that my 25 + year old yanmar doesn't leak with synthetic. Is that old enough for you ? Just think how good your ford 5000 may run with synthetic if it runs well with dino .
If you will re-read my original message, you will notice that I mentioned '70's
Many of our yanmar fall into that range.
Old? antique? where is the hard line in the sand? I don't see one? A vehicle from the 80's.. while old for driving standards perhaps.. is not specifically old mechanically. For instance.. take a tractor from the 80's. Could still be like new, even if well used.
Move back tot he 70's and you can see some age creeping one. Every decade you move back you see more age. Specifically as design styles chaged, and you start seeing art deco in the tin work.. etc. Looking at the profiles of many tractors from the 80's, 90's and 00's, they virtually look the same, model dependent. ( boxy models ) Of course.. now with the sloped hoods and contoured body panels coming in very mainline right now, that now 'dates' the boxy models to a different era. etc.
So yes.. old / antique... I don't see an argument point.. it's all grey area.. not black and white.
I'd also bet the enhanced cleaning properties of synthetic lend to some of the leak issues when it is introduced to an older vehicle that has run on dino.. etc.. especially one not maintained very well.
While I'm not knocking synthetic.. I also don't see it as the magical savior of the future.. not yet anyway. Significant engine work was done int he 20th century on quite old oil technology. many of us collectors have vintage equipment only run on older oils.. even non detergent oils, and lower/older grades, and have units that are oem and still within tolerance. Move up a bit and look at more moder dino lube technologies and other engines, and you can see that if you maintain a vehicle, keep clean oil in it, that it will last, if it was designed well.
We bought an 84' mack tractor from a milk plant. They had had the truck since new.. we bought it with about 800K miles on it. The service logs for this truck showed that it had never had engine work.. not even the finicky air compressor. Just oil changes and lubes, and seals and bearings ont he wheels.. etc. Crankcase held 10+g of oil.. It was being run on bulk diesel rated fina 30w, per the service records. We dropped the pan and plastigauged the mains... they were so far in tolerance, we buttoned her back up with a new pan gasket and put her right on the road with out changing the shells.
Now.. if dino oils is so bad.. that couldn't have happened. Truth is, synthetic may perform better.. however, engine technology from the 20th century was running fine on dino. Specific problem areas like hi-temp, hd turbo systems, and high tolerance areas were greatly benefitting from the improvements in synthetic oils. the key is maintenance... If you have a quality product, and maintain it per the manufacturers specs.. you should expect it to last up to, or past it's designed service life... etc. <ost of the engine problems I see on tired old worn out machines are from outside damage, mis-use, abuse, and abject neglect, malicious acts, and improper maint techniques, fluids and aprts.. etc.
A loose hub retainer nut is going to make more difference to the service life of a spindle and bearing set, and thus seal, than the difference in an 84 Cent per tube cheapy TSC grease, vs a 5$ tube of synthetic grease, when the bearings are packed.. etc.
Soundguy
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