Zinc additive by rislone ZDDP

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robertthoyer

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Since older Lycoming engines have flat tappets and wear more on cam and lifters I have started to add a pint of this product at oil change. I use victory xc 20w50 which has AW lyc additive also. Can there be any harm having too much zinc. On my latest oil analysis I see an increase in iron fe from 85. To 133.47. Checking the filter element shows no chips or metal or anything very clean. Sump screen same. The engine has over 5000 hrs SN. And 360 hrs SMO. Oil burn is a Qt/15hrs. The eng parameters based on my MV 50 eng monitor all good low temps cht mid 300s egt below 1450.
Not sure if zinc can increase the iron. Which its suppose to decrease iron ppm. Prior to using zinc additive the levels were 68, then 85 and now 133
 
First thing I would do is drain the oil, cut the filter again and stop using additives.
Only additives I trust is cam guard and the lycoming additive.
That is a lot of hours, good job taking care of it.
Good luck with it.
 
robertthoyer said:
Since older Lycoming engines have flat tappets and wear more on cam and lifters I have started to add a pint of this product at oil change.
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FYI: aircraft engines are not vehicle engines even if they share similar design components. They each operate in completely different environments and conditions and not to mention one is air-cooled and the other liquid cooled. While additives do have their place, I would not recommend using one simply based on the label.
 
There are plenty of good studies (white paper type material) on ZDDP and its effects. Short answer is yes, there are limits to how much ZDDP is good.

FWIW, ZDDP is not used in the typical aircraft engine oils. I would not be adding a bunch of anything to the oil without knowing what effects it will have. This board is not where I would start my investigation on it. (I’ve done some investigation on its use in E/AB applications and have found no conclusive information to date yet.)
 
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Bell206 said:
FYI: aircraft engines are not vehicle engines even if they share similar design components. They each operate in completely different environments and conditions and not to mention one is air-cooled and the other liquid cooled. While additives do have their place, I would not recommend using one simply based on the label.
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I mentioned Dan but I'm guessing you have some good input also. ;)

My experimental uses a Corvair conversion so while it is air-cooled it isn't a true aircraft engine. Corvair flyers use oil with ZDDP (Rotella 15W40) and some do add a bit more during the initial break-in run. Latest reports are that Rotella contains ~1200 ppm and is required for these flat tappet conversions.

I also run it in my old air-cooled VW and my water cooled Honda motorcycle with excellent results.

It's wise to use what the engine manufacturer gives as guidence ...
 
Valvoline VR1 also has high zinc ZDDP. I didn't know Rotella had it as well.
 
FORANE said:
Valvoline VR1 also has high zinc ZDDP. I didn't know Rotella had it as well.
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I ran the VR1 in my VW conversion on a previous Sonex I had. Yep ... it has the ZDDP and it's good oil for flat tappet engines. A lot of owners of older cars like VR1 and use it for that reason.
 
Read this: https://generalaviationnews.com/2017/05/22/for-oils-its-all-about-the-chemistry/

Basically, zinc can attack copper-based alloys like the bronze valve guides commonly used in aircraft engines, and the rocker bushings. Being a metal, it forms deposits in the cylinder that glow and can cause preignition or detonation, and once that starts the engine's life is measured in minutes. Aircooled engines are much more prone to that than an liquid-cooled engine. Cylinder head temps are much higher.

Somewhere once I read that it can also cause problems with the magnesium often found as an alloy in the crankcases. But that's long ago and I don't remember. I do remember that I read that as I was trying a 15W40 diesel engine oil in my A-65. I took it out after that.
 
Can one legally use an automotive oil additive in a certified aircraft engine?
 
Oils for aviation engines like Conti & Lycoming must be ashless. This means they can't contain metals like Calcium or Zinc (among others). If you add Zinc to your aviation oil, it is no longer ashless and does not meet the engine manufacturer requirements.

Automotive engine oils are not ashless and have much higher levels of these additives. This makes them incompatible with aviation engines.
 
Domenick said:
Can one legally use an automotive oil additive in a certified aircraft engine?
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Technically, there is no FAA rule that says you can’t use them. There’s also no requirement that standalone fuel or oil additives require FAA approval or acceptance. It’s the proverbial gray-area that the use of MMO and other similar products fall under when used on TC’d aircraft.

However, if their use is abused which leads to an aircraft incident or accident, then the additive might get called out as a contributing factor. The main issue with additives comes from the engine OEMs/shops who may void your warranty or other claims for using an “non-approved or non-acceptable” additive in their engines.
 
Dan Thomas said:
robertthoyer said:
Since older Lycoming engines have flat tappets and wear more on cam and lifters I have started to add a pint of this product at oil change. I use victory xc 20w50 which has AW lyc additive also. Can there be any harm having too much zinc. On my latest oil analysis I see an increase in iron fe from 85. To 133.47. Checking the filter element shows no chips or metal or anything very clean. Sump screen same. The engine has over 5000 hrs SN. And 360 hrs SMO. Oil burn is a Qt/15hrs. The eng parameters based on my MV 50 eng monitor all good low temps cht mid 300s egt below 1450.
Not sure if zinc can increase the iron. Which its suppose to decrease iron ppm. Prior to using zinc additive the levels were 68, then 85 and now 133
Click to expand...
Thanks for all feed back , I am using the same product in three airplanes and the others including the rt eng on Apache oil analysis is all normal . The same results as prior to using additive.
From Lycoming:
View attachment 126818
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View attachment 126820
https://www.lycoming.com/sites/default/files/attachments/SI1014N%20Lubricating%20Oil%20Recommendations.pdf

From Continental:

View attachment 126821
View attachment 126822
View attachment 126823
View attachment 126824
https://pceonline.com/wp-content/uploads/2017/04/M-0standardpractice2017-01-15.pdf
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Thank you all for feed back. I called Rislone about ZDDP adaptive. I got engineer chemist on the line and wanted to know if it was harmful to aviation engines using ashlessdispersant . He said no worries and product was designed for flat tappets to prevent cam and lobe wear.
 
You know ZDDP is a metallic additive, right? And what "ashless" means in the context of engine oil? So it doesn't seem like a difficult decision - follow the engine manufacturer guidance, provided to you in detail above, or the advice of an "engineer chemist" who wants to sell you an oil additive.

If ZDDP were appropriate for use in Lycoming engines, you might wonder why Lycoming developed LW-16702. There's a reason why UOA on an aircraft engine has Zinc around 5 ppm, where for cars it can be > 1000 ppm.
 
robertthoyer said:
Thank you all for feed back. I called Rislone about ZDDP adaptive. I got engineer chemist on the line and wanted to know if it was harmful to aviation engines using ashlessdispersant . He said no worries and product was designed for flat tappets to prevent cam and lobe wear.
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He probably ought to update Lycoming of his information. They’d love to hear from someone who knows more about their engines than they do.
 
The whole ZDDP thing borders on a conspiracy theory. Sure you'll get testimonies from people who put it in their engines and had "good results" but then there are thousands of people who didn't put it in with equally good results. It all started about 20 years ago in muscle car forums but the mountains of destroyed camshafts never did appear and the oil companies dealt with it by adding it to some of their products and charging extra for it. If you do research you're not going to find any actual data, just unsubstantiated claims of it's miraculous properties.
 
robertthoyer said:
Thank you all for feed back. I called Rislone about ZDDP adaptive. I got engineer chemist on the line and wanted to know if it was harmful to aviation engines using ashlessdispersant . He said no worries and product was designed for flat tappets to prevent cam and lobe wear.
Click to expand...
Just because it was "designed for flat tappets to prevent cam and lobe wear" does NOT mean it is suitable for an aircraft engine. Your personal experiment on a 5000 hour SN engine will be interesting to follow.

robertthoyer said:
... Not sure if zinc can increase the iron. Which its suppose to decrease iron ppm. Prior to using zinc additive the levels were 68, then 85 and now 133.
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I wonder how abrasive is the ash from Zinc dialkyldithiophosphate? I also wonder what 5000 hr main bearings think of zinc ash.
 
Domenick said:
Just because it was "designed for flat tappets to prevent cam and lobe wear" does NOT mean it is suitable for an aircraft engine. Your personal experiment on a 5000 hour SN engine will be interesting to follow.


I wonder how abrasive is the ash from Zinc dialkyldithiophosphate? I also wonder what 5000 hr main bearings think of zinc ash.
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To be fair, the main bearings should only have 360 hours.
 
Mobil engineer chemists were sure their oil was great for aircraft engines.

They were wrong.
 
Pinecone said:
Mobil engineer chemists were sure their oil was great for aircraft engines.

They were wrong.
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www.avweb.com

Mobil AV-1 Under Attack

A class-action lawsuit demands that thousands of TCM 470-, 520-, and 550-series engines that used Mobil AV-1 synthetic oil be grounded for tear-down inspection and overhaul at Mobil's expense. We urge owners not to panic.
www.avweb.com www.avweb.com
 
Domenick said:
www.avweb.com

Mobil AV-1 Under Attack

A class-action lawsuit demands that thousands of TCM 470-, 520-, and 550-series engines that used Mobil AV-1 synthetic oil be grounded for tear-down inspection and overhaul at Mobil's expense. We urge owners not to panic.
www.avweb.com www.avweb.com
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Yup. I remember that full synthetics were causing problems in cars in the 1980s. Gaskets were deteriorating and leaking. Leftover mineral oil in the engine would mix and react with the synthetic, forming sludge. I believe crankcase moisture was also a factor.

Similarly, the "New and Improved" synthetic automotive brake fluids were failing. They were famous for rapidly absorbing moisture from the air, especially in older, non-totally-sealed systems, and causing failures. Corrosion was rampant.

Someone comes up with a new technology, and in the haste to be the first on the market with it and make lots of money before competition gets involved, it doesn't get tested well enough, and problems arise.

Just because it's possible and appears to be better is not a good reason to buy it. Be skeptical. What you're using still works, doesn't it? And it's usually cheaper, too. Wait it out.
 
The problem with seals and early synthetics was the conventional oils had some light fractions that caused the seals to swell and wear with that swelling. The synthetic oil did not have any light fractions, so the seals would shrink and leak. So they added a bit of light fraction to keep the seals swollen.

The sludge issue was that older engines had sludge build up. When you changed to a synthetic, they are naturally clearners, so they broke up the sludge and then the sludge would clog the oil passages. So the advice was to do a good flush of the engine before switching.

In airplanes, the synthetics did not handle the lead build up. So with UL fuels coming, we might be able to go to full synthetics with all the good properties they have.
 
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