Lack of Zinc in oil

I'm sure everyone is aware of the EPA requiring the manufactures to take more zinc out of the oil,I add zinc to my collector cars and run diesel oil in the engines,but just wondering if the collector tractors that are mostly gas shouldn't run either diesel oil or put a zinc additive in them.Has there been any discussion on this before?

I know several people say add zink to the oil after a rebuild to get it to break in. I had trouble with high blow by on my combine after on overhaul, changed oil and refilled with deere break in oil and now blow by is gone.

the lack of zink in the oil is why a lot of small engines fail at an early age -- change your oil often or add zink just saying -- Roy

I've been running diesel grade 15W-40 in all my engines gas and diesel for about 20 years.

That doesn't mean you are getting zinc in your oil unless you have verified that your brand has it. Flat cam followers need it.

(quoted from post at 19:47:53 10/06/17) Flat cam followers need it.

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I respectfully disagree. High horsepower engines with stiff valve springs need it. It is just not an issue in antique tractors. Same thing with small engines.

Just use regular oil as you aren't going on any 2000 mi trip in the heat of the day. Modern oil is quite ok for old motors my 70 plus yr old ones seem to start and run just fine tractor rides for a few days ect mowing yards and the list goes on.

most all newer engines have roller rocker (arms), where zinc comes into play is the older engines and small engines where the rocker contacts the valve stem directly, for added lubricity.

There are millions of "older" engines that are staying alive long after they started cutting zinc out of engine oils around the mid 1990's ZDDP has been reduced from engine oils for a real long time now. Also how much is in the oil you use and how much additive are you going to put in? Too much can do more harm than good.

Most, not all diesel rated oils have more ZDDP but not what it used to have 20 years ago. Racing oils or "off road" oils usually have more too. Whether you think you need it or not, why not consider better oil products like both synthetic and high mileage.

Do you have specific examples of small engine failure due to lack of zinc?

Rotella 15-40 diesel oil in everything from the 17 Model T, 3 tractors all over 65 years old, Dodge diesel, Wife's Jeep Grand Cherokee.
Richard in NW SC

There is still lots of oil around with higher ZDDP. Mobil 1 High Mileage. Amsoil. Shell Rotella T. Most off-road or ag blends will have it. If you buy oil for a small engine like branded by Briggs & Stratton, it has very high zinc.

I have been told jd break in oil is just non-detergent.

What I use.
http://www.drivenracingoil.com/

WGM was wondering what small engine was the most common one to fail because of the lack of zinc -- we see most failures in the larger V-twins -- the cams go flat and the engine looses power -- or the plastic timing gear wears out and breaks

No shortage of info on the web, a lot of it makes sense, some of it is contradictory with other opinions. This little bit of info below sheds some light on the situation as it now stands ..... not that it solves anything but it makes some things a bit clearer. Take note of the "backward compatibility" information, and assuming that is is true, I doubt that many of us here are going to be affected too much using regular off-the-shelf oils in our older equipment. Now, if you are building high performance racing engines, etc ..... that's another kettle of fish. Anyways, a little knowledge is better than none I think, here ya go .....

"All the current gasoline categories (including the obsolete SH) have placed limitations on the phosphorus content for certain SAE viscosity grades (the xW-20, xW-30) due to the chemical poisoning that phosphorus has on catalytic converters. Phosphorus is a key anti-wear component in motor oil and is usually found in motor oil in the form of zinc dithiophosphate (ZDDP). Each new API category has placed successively lower phosphorus and zinc limits, and thus has created a controversial issue of obsolescent oils needed for older engines, especially engines with sliding (flat/cleave) tappets. API and ILSAC, which represents most of the world's major automobile/engine manufacturers, state API SM/ILSAC GF-4 is fully backwards compatible, and it is noted that one of the engine tests required for API SM, the Sequence IVA, is a sliding tappet design to test specifically for cam wear protection. Not everyone is in agreement with backwards compatibility, and in addition, there are special situations, such as "performance" engines or fully race built engines, where the engine protection requirements are above and beyond API/ILSAC requirements. Because of this, there are specialty oils out in the market place with higher than API allowed phosphorus levels. Most engines built before 1985 have the flat/cleave bearing style systems of construction, which is sensitive to reducing zinc and phosphorus. For example, in API SG rated oils, this was at the 1200-1300 ppm level for zinc and phosphorus, where the current SM is under 600 ppm. This reduction in anti-wear chemicals in oil has caused premature failures of camshafts and other high pressure bearings in many older automobiles and has been blamed for premature failure of the oil pump drive/cam position sensor gear that is meshed with camshaft gear in some modern engines."

Joe Gibbs Racing oil is high zinc and Brad Penn brand.

I use a zinc additive when I do all my O/H's,,they won't break in with out it..I went for years with out it and got by probably because the zinc was already in the oil...

Agreed - and to be honest I don't think its an issue at all with antique tractors. They don't have the stiff valve springs that high revving automotive engines have. Many were designed and operated in the days of nondetergentated oil - basically a 0 additive package.