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Old Oct 18, 2017 | 09:56 AM
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Default Another wiped lobe

Got the block in the shop so doing a refresh after 25K on 383 and measured cam lobes. Had written down from 5 years ago 1.530 and almost all the lobes were averaging 1.490 but one was only 1.425 and two others 1.475. I use Mobil 1 the whole time which is suppose to be good according to the oil list in the stickys I think.

Checked the solid lifter for the 1.425 lobe and sure enough its all concave on bottom you can easily tell. The rest of the lifters seem flat.

Was trying to get out of this cheap but new cam and lifters now add $350 extra. This is third premature cam failure I've had and I've tried all the break in procedures and oils to prevent this but still happens.

I think the only real solution to this issue is roller rockers or better cam materials or hardening procedures. Comp cam Magnum 282S. Cant afford rollers unfortunately.
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Old Oct 18, 2017 | 10:31 AM
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I use regular "dino" oil with a high zinc content. Check out posts for Rotella diesel oil on the C-2 side of the forum. Many of us are usi ng it on our flat tappet cams.You could also stick with Mobile One, but add zinc into the crankcase. Zinc additives are available from Eastwood. Jerry
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Old Oct 18, 2017 | 10:51 AM
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Originally Posted by Surfer69
Got the block in the shop so doing a refresh after 25K on 383 and measured cam lobes. Had written down from 5 years ago 1.530 and almost all the lobes were averaging 1.490 but one was only 1.425 and two others 1.475. I use Mobil 1 the whole time which is suppose to be good according to the oil list in the stickys I think.

Checked the solid lifter for the 1.425 lobe and sure enough its all concave on bottom you can easily tell. The rest of the lifters seem flat.

Was trying to get out of this cheap but new cam and lifters now add $350 extra. This is third premature cam failure I've had and I've tried all the break in procedures and oils to prevent this but still happens.

I think the only real solution to this issue is roller rockers or better cam materials or hardening procedures. Comp cam Magnum 282S. Cant afford rollers unfortunately.
You need to use ONLY the original "moly" lube for the cam break-in, toss all the other lubes supplied by almost every aftermarket cam vendor!

All the "old-school rules" still do apply, make sure it fires immediately, keep it up at about 1800 (nominal), and don't let it o'heat.

Use no thermostat during the break-in AND absolutely no anti-freeze either!

Thanks, Gary in N.Y.

P.S. Just curious if it's the same lobes (location) keep going away?? Eventually you will go roller, about 95% of our 100% stock-appearing builds end up there. We also have no need for setting cam end-play or using any cam-buttons anymore on these early SB builds, it's all done with a later cam thrust plate and 2 attaching screws.
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Old Oct 18, 2017 | 12:20 PM
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Mobil 1 is not the right oil for a flat tappet cam.
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Old Oct 18, 2017 | 12:57 PM
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This is a good article: http://www.crankshaftcoalition.com/w...ips_and_tricks

Found it after I wiped a lobe .. lol
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Old Oct 18, 2017 | 01:08 PM
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I have always used Valvoline VR1 with no issues. That being said, I'll switch to roller lifters next time. Much better design.
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Old Oct 18, 2017 | 02:28 PM
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Originally Posted by Surfer69
Got the block in the shop so doing a refresh after 25K on 383 and measured cam lobes. Had written down from 5 years ago 1.530 and almost all the lobes were averaging 1.490 but one was only 1.425 and two others 1.475. I use Mobil 1 the whole time which is suppose to be good according to the oil list in the stickys I think.

Checked the solid lifter for the 1.425 lobe and sure enough its all concave on bottom you can easily tell. The rest of the lifters seem flat.

Was trying to get out of this cheap but new cam and lifters now add $350 extra. This is third premature cam failure I've had and I've tried all the break in procedures and oils to prevent this but still happens.

I think the only real solution to this issue is roller rockers or better cam materials or hardening procedures. Comp cam Magnum 282S. Cant afford rollers unfortunately.

Does your heads have inner springs? If so you're supposed to remove the inner springs during the critical break in. I ran my 454" for a full 1000 miles using the outer springs only. I run 5W30 Parts Master full synthetic oil with no additional additives and my engine now has 30,000 miles on it with no cam lobe problems.
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Old Oct 18, 2017 | 02:58 PM
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This is only one person's assessment...

I suspect that the primary issue with cam lobe wear has more to do with improper grades of steel used and/or inadequate heat treating of the metal, rather than the amount of zinc in the lubricating oil.

Aftermarket parts just do not get specified or manufactured in the same way that was used for original factory parts. Improved metallurgy and improved heat treat processes cost MORE. Aftermarket parts manufacturers (especially those produced outside the U.S.) do not care about any "safety factor" when it comes to part operating parameters; they only want the part to BARELY meet the normal needs of the user. Saving money when producing parts means more money for their pockets--and that is PRIORITY No. !, as far as they are concerned.

The sales outlets merely make that stuff available to us; they have little say in how the parts are made. Their alternative is NOT to sell a questionable product, just as our alternative is not to buy one. So it is up to us to be judicious about the quality of the part we are buying and having some confidence in the manufacturer BEFORE we make that purchase.

I do not know the maker of the cam in question. But I can emphatically claim that it is almost always a bad idea to purchase the lowest cost product for a "important, hard working" component.

Last edited by 7T1vette; Oct 18, 2017 at 03:00 PM.
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Old Oct 18, 2017 | 03:11 PM
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mobil-1-oil-product-specs-guide.pdf

Mobil 1 0W-40 has 1,100 PPM zinc per their spec sheet (attached). This is much higher than most modern passenger car oils, although still a little less than some of the specialty oils. Did some checking and if I looked correctly, Valvoline VR-1 is 1,300 PPM and Brad Penn is 1,500 PPM. I think the 0W-40 is a good product for all but the most severe services.
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Old Oct 18, 2017 | 04:13 PM
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Yea I will switch to different dyno oil this time and make sure new break in is done perfect.
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Old Oct 18, 2017 | 04:20 PM
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Originally Posted by Griff2002
Attachment 48216576

Mobil 1 0W-40 has 1,100 PPM zinc per their spec sheet (attached). This is much higher than most modern passenger car oils, although still a little less than some of the specialty oils. Did some checking and if I looked correctly, Valvoline VR-1 is 1,300 PPM and Brad Penn is 1,500 PPM. I think the 0W-40 is a good product for all but the most severe services.
I'm not seeing that 1100 on the Mobile. I see 900 which should be good enough I guess.
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Old Oct 18, 2017 | 04:28 PM
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synthetic is also very slippery. So slippery that the lifters can fail to rotate in the bores... That will wipe a cam too.
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Old Oct 18, 2017 | 04:34 PM
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After camfailure after break-in I went roller rockers, save up and buy, so much better
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Old Oct 18, 2017 | 04:41 PM
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If I were to make a spreadsheet of all oils with adequate zinc, phosphorus etc none of you, not a single person here could pick a specific oil on request from the list.

All oils sold are ‘modern formula’ oils. Show me 1 oil with a 20 year old formulation. Nope.
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Old Oct 18, 2017 | 04:53 PM
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Zinc plugs up the cats. The EPA tree huggers don't like that remember? There is no need for zinc in engines past 1989 when the roller was introduced or the finger follower and overhead styles cams. Therefore, why would off the shelf oils bother with zinc when its only a small minority of us flat tappers that need it? The Govt banned zinc with the exception of Racing Oil, Off Road Oil and Break-In oil. But we have ways around that.

Last edited by HeadsU.P.; Oct 18, 2017 at 04:54 PM.
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Old Oct 18, 2017 | 04:53 PM
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Weight phosphorus zinc

15w-50 1200 1300
5w-40 1100 1200
5w-30 1000 1100
10w-40 1200 1300
10w-30 1000 1100
10w-40 1000 1100
5w-40 800 900
5w-30 800 900
20w-50 1600 1700
0w-30 1750 1850
0w-50 1750 1850

Which is Mobil 1

Last edited by jim2527; Oct 18, 2017 at 04:56 PM.
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Old Oct 18, 2017 | 04:59 PM
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Sorry jim but those are meaningless numbers without brands. And is that "off the shelf" Walmart Qts?
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Old Oct 18, 2017 | 05:06 PM
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Originally Posted by HeadsU.P.
why would off the shelf oils bother with zinc when its only a small minority of us flat tappers that need it.
Almost all of the 'high mileage' off the shelf oils have high zinc.

I believe the EPA banned phosphorous, not zinc. And its not banned, its just capped at 800ppm.
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Old Oct 18, 2017 | 05:10 PM
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I've used Valvoline VR-1 since my break in. So far so good.
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Old Oct 18, 2017 | 05:15 PM
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Originally Posted by jim2527
Almost all of the 'high mileage' off the shelf oils have high zinc.

I believe the EPA banned phosphorous, not zinc. And its not banned, its just capped at 800ppm.
I trust you. You have never lied to me before. However, I prefer a 1200-1500 ppm with the valvespring pressures I'm pushing.
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