Oil suitable for flat tappets.

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Tore down a 350 chevy flat tappet with regular oil changes and maint. Engine was nice and clean but had no power and would backfire. Cam was toasted. Owner beleives it was from using moderm oil.

So question being, what modern oils will protect flat tappet cams that are stock.

Another example is a Kohler 12HP K301 small engine. Cam lobes were worn right down. This alarms me as small engines have very light spring tension. Oil today must not be made for flat tappets as no automotive engines use it.
 
+1 to Rand and if you want to spend an extra few bucks amsoil Z-Rod is a very good choice as well. Probably one I would use if I needed to. Cheaper option as well is QS Defy and Delo LE 30w which I use in my small engines.
 
Originally Posted By: Fordiesel69
Engine was nice and clean but had no power and would backfire. Cam was toasted. Owner beleives it was from using moderm oil.

That was common with the SBC back in the day when the oil met much older specs. Nonetheless, I share your concern. As Rand points out, try an HDEO. Valvoline VR1 is another fine option. QS Defy would be worth a check, too. Of course, if you have money to burn, there are plenty of boutique options.
 
Originally Posted By: The_Jed
Is Brad Penn a good flat tappet oil?

Their racing oil is suitable for flat tappets.
 
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I'd put VR1 above QS Defy, except maybe Defy in 10w40 flavor.
Defy is a bit of a throwback but they still wanted it to be SL rated, so they don't have the ZDDP level as high in the 30 grades. 10w40 doesn't have the same limits so they raised it more on that grade.
VR1 doesn't care about the API limits in any grade, their 10w30 is classified as SH because of that.

So between those brands the options I'd consider would be:
VR1 10w30
QS Defy 10w40
VR1 10w30+20w50 mixed (they don't sell a multigrade Xw40)

Brad Penn is good and has more viscosities, maybe you can get it local where you are. For many people VR1 is more readily/cheaply available but you're in PA.
 
Originally Posted By: tig1
As we know Chev V8s had problems with soft cams in the 70s and 80s.


Yes indeed. My grandfather used nothing but SAE 30 HDEO in his 307 powered Caddy, it still needed a new cam at 100k.

Put a new cam kit in the 350, and refill with a 10w30 HDEO of your choice.
 
Since you're in Pennsylvania, Brad Penn oils may be readily available. They have slightly higher zddp than Valvoline VR1.

Valvoline VR1 conventional is available in every NAPA that I've been in, although you may have to get them to order the 10w30 for you. I run VR1 in my '72 GMC pickup with a Chevy 307, and it runs very well.
 
This subject has been beaten to death.
Yes the SM and SN oil specs have reduced zddo however they have made up for it with the use of friction modifiers,so the whole issue is mute.
If you are really that concerned then find an oil that is still SL rated. Like German castrol or any diesel oil will also work.
 
Do have you pictures of the cam in question? That would go a long way in helping diagnosing the cause of failure. Despite the internet myth's older pcmo's did not have boatloads of zddp and had additives that would be determined detrimental.
 
Originally Posted By: Rob_Roy
Originally Posted By: tig1
As we know Chev V8s had problems with soft cams in the 70s and 80s.

Yes indeed. My grandfather used nothing but SAE 30 HDEO in his 307 powered Caddy, it still needed a new cam at 100k.

Not just V8s...I had an '80 Malibu V6 company car back in '84 and it wore out the cam in under 100k.

Side note: it was the slowest car I have ever driven. Was blown off the road by an '80s Dodge...something...(Dart? Valiant?) with a /6, full of hooting teenagers. It was pathetic.
 
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