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General Tech Zinc in the Oil

KVH

Obi Wan
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Can I just add two quarts of 50 weight Valvoline racing oil with zinc to my 20-50 weight regular Valvoline and be comfortable I've got enough zinc?

Also, when I put a new cam in 10 years ago, I just used heavy assembly lube. I wasn't aware I needed to add zinc paste to the lobes and run 30 minutes at 2000 rpms for break in.

I know it's conjecture, but here I am ten years later hearing a little ticking around the lifters, and no amount of valve adjustment will cure it. Could it be that lack of zinc these years have those lifter worn badly. As I recall I really only added zinc to my 20-50 oil maybe one or two times--until I started adding some 50 weight Valvoline with zinc.

Thx for the thoughts.
 
I doubt that the lack of zinc is causing the valve ticking after all these years. I would look into rocker arm recession just over the valve stems. When little divots form in the rockers, it makes it all but impossible to set the valves correctly. If they're not too bad, they can be dressed up to get rid of the divot. Look at the profile on a good rocker. There's a slight curve to it, so that's how you would want to dress the bad rockers.
 
I wonder how many miles in those 10 years? Tom
 
Just curious. Would the use of the "Klik-it" valve adjusting tool overcome the problem of rocker arm recession?
 
On the first question in this thread, several good articles can be found by googling ZDDP.What I say here comes from those sources. Apparently, zinc and phosphorous work to provide a coating on engine parts that smoothes out the metal on a molecular level. Racing oils in street cars is not a good idea. The percentages of ZDDP have to be in a particular range tailored to the loads on engine parts. Detergents can adversely affect the zinc and phosphorous. Just use a good oil that is rated for older cars.
Bob
 
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