oil with out zink

cvicky

cvicky

Senior Member
some say youneed to add oil with zink in 50-60s' engines others say no

so far ive been getting away with bargain brand multy grade 10w30

am I looking for trouble
 
Every body has a different opinion about this. I heard from a noted Yblock engine builder that any oil with a 30 weight or greater has enough zinc in it for Y blocks and I would assume flatheads. So I 10/30, 10/40, 20/50 should be sufficient without an additive. 60's oil had less ZDDP (zinc blend) that most of the oils noted above. He uses Valvoline 10/30 or 10/40 conventional in all his builds


But as I said, every one has a different opinion on this.
 
I'm on the Zinc side of the fence.
I was using an older Rotella 10/40 oil but switched to Valvoline VR1 Racing/High Zinc 20/50
~High performance formula for flat tappet engines~

"am I looking for trouble"
Valve train wear may or may not take a while. How many miles do you drive it a year? Some off-shore sourced parts (valve adjusting screws) can fail in a few weeks no matter which oil is used.

50's, 60's & some 70's motor oil used to contain zinc (& phosphorus) to help reduce wear at the high stress pressure points in the valve trains of older engines. But with the advent of unleaded fuel, catalytic converters, hydraulic and roller lifters... the zinc & phosphorus wasn't as needed and it contaminated emission equipment... so it was removed.

I think of high Zinc oil as insurance. Might never need it or know that I did, but I don't want the cam to go flat either.

More info at this link... https://www.ctci.org/engine-oil/
.
 
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dmsfrr said:
I'm on the Zinc side of the fence.
I was using an older Rotella 10/40 oil but switched to Valvoline VR1 Racing/High Zinc 20/50
High performance formula for flat tappet engines

"am I looking for trouble"
Valve train wear may or may not take a while. How many miles do you drive it a year? Some off-shore sourced parts (valve adjusting screws) can fail in a few weeks no matter which oil is used.

50's, 60's & some 70's motor oil used to contain zinc (& phosphorus) to help reduce wear at the high stress pressure points in the valve trains of older engines. But with the advent of unleaded fuel, catalytic converters, hydraulic and roller lifters... the zinc & phosphorus wasn't as needed and it contaminated emission equipment... so it was removed.

I think of high Zinc oil as insurance. Might never need it or know that I did, but I don't want the cam to go flat either.

More info at this link... https://www.ctci.org/engine-oil/
.
Click to expand...



I am with you on this. I use Valvoline VR1 also in my avatar 302. One oil change a year won't break the bank!!
 
The ZDDP was not completely removed. It was just reduced. The higher performance engines of the late 50s through the early 70s needed 1200 PPM of ZDDP for better longevity of flat tappet valve train components. The first reduction brought the levels down to 1000 PPM and further reductions reduced it to 800 PPM so it's still in there but at a reduced amount.
 
cvicky said:
some say youneed to add oil with zink in 50-60s' engines others say no

so far ive been getting away with bargain brand multy grade 10w30

am I looking for trouble
Click to expand...




You're doing great. There is enough zinc in the oii you're using. One requirement for oil to meet new standards is that it be backward compatible to meet previous standards. So no need to worry unless you have a high zoot race engine with aftermarket extreme pressure valve springs.
 
Todays Valvoline premium blue 15W-40 deisel oil has 1270ppm zinc. I've been using it for many years. My 292 has a zillion miles on it and still runs great.
 
I agree with dmsfrr, I use zinc in my Y-block with 10-30. I figure that it is cheap insurance. $15 every 3000 miles is not going to break me! I add it with every oil change.
I also used zinc in my '81 SBF 302 with Mobil 1 Synthetic 10-30. added the zinc every filter change(3K mi) , changed oil every year and we drove the car, as I remember about
7-8K miles a year.
 
Anything more than 1200 ppm starts to become detrimental to the engine parts. This was where the API set the limits for good reason (for automobile engines). ZDDP has corrosive properties so don't get too carried away with it. Most diesel engines have larger & heavier duty parts than car engines so they did use higher amounts. The latest API CK-4 rating has reduced levels of ZDDP. Some of them are skirting the API CK-4 rating by listing the engine protection test results. They don't pass for that rating yet but if they eventually do then they won't have much more ZDDP than car engine oil has. They will just use other additives like they have for years. Diesel truck oil is overkill for most automobiles. The stuff helps with the high perfomance engines that started to show up in showrooms in 1958 but the earlier designs really would only need it for initial break in. After that, they would work just fine. The old flatheads don't need it at all. Rompum stompum engines with high compression and high lift, flat tappet cams will be the only ones that benefit from high ZDDP levels. Roller cams don't need high levels.
 
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80's oil had less than 800 PPM


Go here for some facts


https://www.ctci.org/gilsgarage/engine-oil-part-2-engine-oil-and-zddp/



rotorwrench said:
The ZDDP was not completely removed. It was just reduced. The higher performance engines of the late 50s through the early 70s needed 1200 PPM of ZDDP for better longevity of flat tappet valve train components. The first reduction brought the levels down to 1000 PPM and further reductions reduced it to 800 PPM so it's still in there but at a reduced amount.
Click to expand...
 
The scare from the lack of ZDDP has been around since the mid 70's. Most people didn't realize it and most Ford engines didn't suffer from it. Both small and big block Chevys are the ones that suffer the most with flat tappet cams. 1 out of 5 of those cams went flat even before the ZDDP was reduced. I don't get to concerned about the oil in my old Fords, but my Chevy friends do
 
rotorwrench said:
Anything more than 1200 ppm starts to become detrimental to the engine parts. This was where the API set the limits for good reason (for automobile engines). ZDDP has corrosive properties so don't get too carried away with it. Most diesel engines have larger & heavier duty parts than car engines so they did use higher amounts. The latest API CK-4 rating has reduced levels of ZDDP. Some of them are skirting the API CK-4 rating by listing the engine protection test results. They don't pass for that rating yet but if they eventually do then they won't have much more ZDDP than car engine oil has. They will just use other additives like they have for years. Diesel truck oil is overkill for most automobiles. The stuff helps with the high perfomance engines that started to show up in showrooms in 1958 but the earlier designs really would only need it for initial break in. After that, they would work just fine. The old flatheads don't need it at all. Rompum stompum engines with high compression and high lift, flat tappet cams will be the only ones that benefit from high ZDDP levels. Roller cams don't need high levels.
Click to expand...

I humbly disagree. My truck is a 71 stock 6cyl and PYB 10w-30 high mileage almost ruint my cam and did damage a lifter. I now have 15w-40 delo in it with an additive in it. I put the whole bottle in and I only needed 1/4 a bottle, but my engine runs real good on 5000+ppm of zddp. Wish I could get ahold of some old 30wt delo, but I may try some of that renagade 3000ppm oil or penn grade(brad penn). Now valvoline racing would be my last resort, but is an option. I just don't want to trust this epa mandated car oil anymore. Who wants to trust the government to protect their engines?
 
paul2748 said:
80's oil had less than 800 PPM


Go here for some facts


https://www.ctci.org/gilsgarage/engine-oil-part-2-engine-oil-and-zddp/
Click to expand...

Paul, I believe you posted that in good faith, but I don't trust the article. I think there are a lot of propaganda articles out there to control what people think. I was a teen in the 80s and my dad worked on his own stuff and I knew some hot rodders also. The oil never gave any trouble that I'm aware (unlike the lower zddp oils of today) of except for some cheap store brands and the rumors to stay away from quaker state and stp. I've read the articles including the one on modern oils that give higher psi flow (now pressure). I bought into them and almost ruint my engine on that stuff. Can you really blame me if I'm more sceptical than ever now?
I was about as gullable as a blonde haired dude could get, but as Abraham Lincoln once said--you can't believe everything on the internet because there is no way to prove that it's true....lol
 
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