Shorter Oil Change Interval - flat-tappet engines?

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I just got off the phone with a friend whose an engineer and asked him to help me solve a problem I was having on getting the right level of phosphorus in my oil (want 1000-1100 Phos. in a dedicated gasoline-rated 10w30 oil). I rather not use ZDDP additives; VR-1 and Red line oils are too high in Phos; Mobil 1 is too low; the Rotellas are super-loaded with detergents and not really designed for gas engines; and the many other brand 10w30, the manufacurers don't have the info in their data sheets.

My friend said: "Just use regular 800 ppm phosphorus, SM rated oil in your flat-tappet engine and change the oil at 2 months 2000 miles instead of 3/3000. It will ensure adequate levels of ZDDP present in your oil at all times. The ZDDP is used up as you drive, so just change it sooner..."

If this is true, then this is cheap way to fully protect a flat-tappet engine. Please comment on this plan...
 
I'm thinking I can use a cheaper locally purchased oil and save the $ there, and also not have the hassle and expense (and chemical unknowns) of using additives. I really want to keep my ol' flat-tappet going for a long while!
 
I think that HDEO does not have too many detergents in its current specs. CI4 or CI4+ did, but the detergent levels are down in the new CJ4 spec oil. Rotella has been keeping our big blocks with flat tappets alive and well for a while now.
 
Originally Posted By: Torrid
Have you considered Mobil 1 high mileage formula? It has the ZDDP level you are looking for.


Went to the Mobil 1 site, and the 10w30 high mileage is listed with only 900 ppm Phos. Thanks for help, though...
 
Originally Posted By: Gunner14
Originally Posted By: Torrid
Have you considered Mobil 1 high mileage formula? It has the ZDDP level you are looking for.


Went to the Mobil 1 site, and the 10w30 high mileage is listed with only 900 ppm Phos. Thanks for help, though...


They lowered it? [censored]. I'll check some PDS forms and get back to you.
 
Originally Posted By: Torrid
Originally Posted By: Gunner14
Originally Posted By: Torrid
Have you considered Mobil 1 high mileage formula? It has the ZDDP level you are looking for.


Went to the Mobil 1 site, and the 10w30 high mileage is listed with only 900 ppm Phos. Thanks for help, though...


They lowered it? [censored]. I'll check some PDS forms and get back to you.


The Mobil 1 (updated 5/27/10) Engine Oils Sheet shows 900 ppm P.

Back to my initial question: What about changing cheaper SM oil sooner? Will that keep my ZDDP levels high at all times ???
 
[quoteI
The Mobil 1 (updated 5/27/10) Engine Oils Sheet shows 900 ppm P.

Back to my initial question: What about changing cheaper SM oil sooner? Will that keep my ZDDP levels high at all times ???[/quote]

I don't think it works that way. ZDDP isn't like calcium where it depletes to absorb acid. The higher ZDDP is mostly there to protect cam lobes if you lose oil pressure because it sticks to metal parts to prevent metal on metal contact.
 
Originally Posted By: Torrid
[quoteI
The Mobil 1 (updated 5/27/10) Engine Oils Sheet shows 900 ppm P.

Back to my initial question: What about changing cheaper SM oil sooner? Will that keep my ZDDP levels high at all times ???


I don't think it works that way. ZDDP isn't like calcium where it depletes to absorb acid. The higher ZDDP is mostly there to protect cam lobes if you lose oil pressure because it sticks to metal parts to prevent metal on metal contact. [/quote]


I'm pretty sure that ZDDP is a sacrifical additive and that the danger is that it will deplete before the next oil change (thus higher amounts in flat-tappet oils to keep the level up)- if anyone knows about this, please comment...
 
I'd be curious as well. I don't think that is right, but I am still learning and am willing to learn more.
 
Originally Posted By: Gunner14

Back to my initial question: What about changing cheaper SM oil sooner? Will that keep my ZDDP levels high at all times ???


No, it does not work that way. ZDDP additives are NOT depleted over an OCI, that can be born out by looking at VOA vs. UOA, there are many posted on this site. The ZDDP numbers don't materially change.
 
I don't buy the argument of Rotella "not for gasoline engines". The SM rating ain't for nothing. My engine builder has built and supported gasoline engines for years recommending Delo (his favorite). I've bought Rotella as it's easier to get in 10w30, at a little over $4/quart. I admit to about an ounce of CamShield for piece of mind as I have fairly stiff spring pressures.

After about 10K miles, it's too early to tell how this strategy will work 100K from now, but it burns virtually zero oil and the pistons are quite short (including track days where I use Delo 15w40).
 
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Gunner,

Changing every 2 months,2000 miles is crazy.

I like the Mobil 1 0w40 suggestion. 0w40 has 1000ppm of Phos.

If you don't want the expense of synthetics, use VR1. It has the amount of Phos that was acceptable for flat tappet engines back in the day. Or mix it 50/50 with Valvoline SN MaxLife red bottle, and then you have 1000ppm Phos.

I agree with you wanting to use an oil primarily formulated for gasoline engines. Diesel oils have harsh detergents that compete for surface coverage with the zddp, making it less effective.
 
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ZDDP doen not get used up that is false. It is a last step additive to help the engine survive against metal on metal.

Think of it as a fire extingusher, It sits under you cabinet for 3 months its not getting used up, but when there is a fire you use it to avoid a catastraphe.
 
Originally Posted By: A_Harman
Gunner,

Changing every 2 months,2000 miles is crazy.

I like the Mobil 1 0w40 suggestion. 0w40 has 1000ppm of Phos.

If you don't want the expense of synthetics, use VR1. It has the amount of Phos that was acceptable for flat tappet engines back in the day. Or mix it 50/50 with Valvoline SN MaxLife red bottle, and then you have 1000ppm Phos.

I agree with you wanting to use an oil primarily formulated for gasoline engines. Diesel oils have harsh detergents that compete for surface coverage with the zddp, making it less effective.


It never occured to me to mix two oils to get the ZDDP level I wanted! Thanks for this advice. I'm going to call Valvoline, and see which other oil is the best match to the VR-1. It seems that their Premimium Conventional Oil is what the VR-1 (non-syn) is based off. I'll post what they tell me. Thanks again for the info... Gunner
 
Yes, it seems like Valvoline uses similar additive packages across their product line. I have noticed before that VR1 Synthetic has exactly the same chemical analysis as Synpower, only with increased zddp content.
 
Originally Posted By: A_Harman
Yes, it seems like Valvoline uses similar additive packages across their product line. I have noticed before that VR1 Synthetic has exactly the same chemical analysis as Synpower, only with increased zddp content.


UPDATE: Just finished talking with a Valvoline tech rep: The VR1 (non-synthetic) is based on their "premium conventional motor oil (PCMO)". He verified that the VR1's Phosphorous level is 1300 ppm and indicated that it was fine to mix the VR1 and the PCMO to get the desired ZN/Phosphorus. He stated that both the VR1 and PCMO have an OCI of 3 months/3000 miles. I asked him about mixing VR1 with their Max-Life products, and he indicated that the extra detergents/additives in the Max-life products would inhibit the effectiveness of the extra ZDDP at some level.
 
Originally Posted By: Gunner14
I asked him about mixing VR1 with their Max-Life products, and he indicated that the extra detergents/additives in the Max-life products would inhibit the effectiveness of the extra ZDDP at some level.


I don't recall this idea ever being discussed here. Many people choose a HDEO for particular engines (I'm thinking flat tappet and air cooled outdoor power equipment) with the idea that the higher additives (ZDDP in particular) help protect better in these harsher uses.

Now you are suggesting that the higher detergent levels defeat the extra ZDDP? I wonder what the Valvoline tech. meant by "inhibit the effectiveness of the extra ZDDP at some level."
 
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