Mountain vs. Mole Hill - Zinc Oils

boat dr VS M3Fan, newest CCF fued???

So basically (factory options for CC) every engine PCM has made to date has a flat tappet cam???

Boat Dr, cool it. Please point out where I even expressed an opinion either way? I did nothing but ask questions, clearly prefacing it with a disclaimer about being a devil's advocate. I've heard you were a good guy from a few guys at the reunion- let's not spoil your image here. I think it's important that we're always asking questions and questioning common thinking, and that's what I'm doing here. Looking at issues from all sides. I'll refrain from typing a more livid/profane response at the moment.

Another

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M3Fan wrote: Could this be an issue reserved for more aggressive cam lobes seen on higher-performance engines? Further, who has broken down a flat tappet engine that has been running for 1000 hours and looked at the cam? How did the old cam look? TRBenj, how did the cam look in the 90 when you took it out?

A few points:

- Modified engines with more aggressive (higher lift) cams, and more importantly, stronger valve springs are certainly more susceptible to failure with the newer oils. This is due to the greater forces that exist between the cam and lifter.

- The reduction of the zinc/phosphorus additives has been a gradual one. The process started in the mid 80's since most motors by then had gone roller. However, it hasnt been until very recently that the standards have all but eliminated them from most modern oils. The 15w40 Rotella (my oil of choice) is now included in that group, where a year ago it was not. This article in HotRod is a good read.

I didnt inspect my old cam very closely- but I doubt it would show serious signs of wear. Upon disassembly, it was clear that the motor had been well maintained- and thats more than half the battle. The older grades of oil (from just a few years ago) that had been run in it surely contained more additives than the current oils do, so it was adequately protected (even with the Fram filters .)

The point is that the standards keep reducing the additives, so those of us with flat tappet motors just need to be careful. Those of us with bigger cams and springs need to be extra cautious. Its not about spending more money (Rotella oil and Wix filters are very economical), its just a matter of staying informed. I havent built enough motors (1) to have experienced any failures, but Ive heard the stories and Im not taking any chances. I'll be switching to the straight 30w or 40w.

Gang, time to play devil's advocate here. Flame away: Has anyone personally replaced a cam on a flat-tappet ski boat motor because of wear from using non-zinc oils? Or, has anyone even heard of someone replacing a cam on our PCM marinized Ford powerplants specifically, ever, purely do to wear despite regular oil changes with any reasonable (multi or straight 30 or 40w) oil? Could this be an issue reserved for more aggressive cam lobes seen on higher-performance engines? With our engines running 4400-5k RPM with stock marine cams and generally very mild modifications, is there a reason to really panic on this whole oil with zinc thing?

Further, who has broken down a flat tappet engine that has been running for 1000 hours and looked at the cam? How did the old cam look? TRBenj, how did the cam look in the 90 when you took it out? I'm sure that thing has seen a variety of oils over it's 18 year lifespan.

Obviously oil is cheap and getting the best oil is great, cheap insurance, and I'm all for it. I'm just trying to reign in the panic on the lack of zinc additives in newer oils and really get a scope assigned to the problem.