Flat tappet cam failures
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Joined: Dec 2007
Posts: 79
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From: Pearland Texas
Flat tappet cam failures
I'm sure the people on this forum have already addressed this problem, but after losing cams in a couple of high dollar restorations (both big block Mopar's) I've been doing, I called Comp Cam's about the problem and they have a bulletin they send out (apparently my ego/ ignorance/ stupidity caused me not to read them) with each cam shaft warning of problems with modern oil in flat tappet cams and new oil formulations.
Who knew?
Engine break in with their oil additive is highly recommended and they specify Rotella T (diesel truck oil) as the standard for our use.
I'm sure the name brand equilivants would work too if you have a brand preference.
I changed to this schedule and haven't had a problem since. In fact, I use a couple of ounces of the additive when I change my oil just to be safe. I know its expensive but it only takes a little, and engines are expensive too.
I hope haven't wasted to much space here and this saves someone a camshaft.
Skip in Houston
Who knew?
Engine break in with their oil additive is highly recommended and they specify Rotella T (diesel truck oil) as the standard for our use.
I'm sure the name brand equilivants would work too if you have a brand preference.
I changed to this schedule and haven't had a problem since. In fact, I use a couple of ounces of the additive when I change my oil just to be safe. I know its expensive but it only takes a little, and engines are expensive too.
I hope haven't wasted to much space here and this saves someone a camshaft.
Skip in Houston
NCM Grand Opening Veteran
Joined: Sep 2005
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From: South of giving a damn
St. Jude Donor '11, '17
Old news here. Flats tappets MUST use zinc additives or you risk catastrophic cam failure. This is one reason many have switched to rollers on their rebuilds.
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
The new formulations of automotive oil have changed.....
here is a question asked of Mobil.......
http://www.mobiloil.com/USA-English/...otor_Oils.aspx
Zinc/Phosphorus levels were reduced to improve catalytic converter efficiency/life.
A few guys in our club use diesel oil in their older muscle car engines as Diesel oil DOES contain higher levels of zinc/phosphorus.
here is a question asked of Mobil.......
http://www.mobiloil.com/USA-English/...otor_Oils.aspx
Zinc/Phosphorus levels were reduced to improve catalytic converter efficiency/life.
A few guys in our club use diesel oil in their older muscle car engines as Diesel oil DOES contain higher levels of zinc/phosphorus.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
The best alternative is if everybody would quit buying junk pot metal cams from Comp Cams.
Comp cams got me a couple of times and you are not supposed to say anything on a forum. But they "CC" just don't care!
Comp cams got me a couple of times and you are not supposed to say anything on a forum. But they "CC" just don't care!
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
You'll also need a cam button to keep the cam from walking & might as well get roller rockers. (shafts if you can afford them) Pushrods will have to be checked for correct length. (I'd replace them)
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
A expensive rev kiit, to keep those heavy lifters on that expensive cam.
A really good set of double valve springs, to keep the valves from floating..
A compatible distributor gear, to keep from distroying the distributor gear.
At least a button for the timing cover, to keep the roller cam from walking around {back and forth}
A set of compatible push rods, compensated for the added length of those heavy roller lifters.
Cut your valve guides,
A set of new retainers,
Simple wasn`t it, thats all thats too it...
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From: Tucson AZ
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Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
DON'T USE Diesel oil in a high RPM gasoline motor, you are a FOOL if you do, besides, they are removing all the ZDDP from Diesel oils too. Some oils for you to look up/use: Brad Penn racing (NO! it's not Jeff Spicolli's brother!), Joe Gibbs oil, Motul (really EFFING expensive!) Mobil1 MOTORCYCLE oil, Valvoline Racing "not for street use" oil, any oil with a high ZDDP additive package (ZDDP is Zinc extreme pressure lubricant, Zinc=Lead=fouled catalytic convertor so the ZDDP is being eliminated from all oils INCLUDING Rotella for the new Diesel motors with catalytic convertors.) I do like Rotella in my truck, it has a little silver badge on the side "Duramax/Allison" that says it all 
Race Director
Joined: Apr 2003
Posts: 19,347
Likes: 654
From: Tampa, Florida
If they're not a vendor you should be able to bash them all you want...
DON'T USE Diesel oil in a high RPM gasoline motor, you are a FOOL if you do, besides, they are removing all the ZDDP from Diesel oils too. Some oils for you to look up/use: Brad Penn racing (NO! it's not Jeff Spicolli's brother!), Joe Gibbs oil, Motul (really EFFING expensive!) Mobil1 MOTORCYCLE oil, Valvoline Racing "not for street use" oil, any oil with a high ZDDP additive package (ZDDP is Zinc extreme pressure lubricant, Zinc=Lead=fouled catalytic convertor so the ZDDP is being eliminated from all oils INCLUDING Rotella for the new Diesel motors with catalytic convertors.) I do like Rotella in my truck, it has a little silver badge on the side "Duramax/Allison" that says it all
If you do a search theres good threads about this. There are alot of gasoline oils out there with the old formulation. In fact Mobil has just re-released an oil to specificaly adress this isssue. Most high mileage oils have the high zinc.
Some linkages for you:
http://forums.corvetteforum.com/show...3&postcount=10
http://forums.corvetteforum.com/show...8&postcount=11
Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
Pity of it is, catasstrophic converters are one of the largest automotive frauds ever pulled off on the public....for non existant reasons.....now we can't even get decent OIL anymore....gone well beyond stupid...to the sublime....just ANYTHING to kill off old cars and force sales of more 30,000 dollar POS 'cars' on the public.....
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
DON'T USE Diesel oil in a high RPM gasoline motor, you are a FOOL if you do, besides, they are removing all the ZDDP from Diesel oils too. Some oils for you to look up/use: Brad Penn racing (NO! it's not Jeff Spicolli's brother!), Joe Gibbs oil, Motul (really EFFING expensive!) Mobil1 MOTORCYCLE oil, Valvoline Racing "not for street use" oil, any oil with a high ZDDP additive package (ZDDP is Zinc extreme pressure lubricant, Zinc=Lead=fouled catalytic convertor so the ZDDP is being eliminated from all oils INCLUDING Rotella for the new Diesel motors with catalytic convertors.) I do like Rotella in my truck, it has a little silver badge on the side "Duramax/Allison" that says it all
Guess I'm a fool.
Racer
Joined: Mar 2006
Posts: 291
Likes: 0
From: Guantanamo Bay, Cuba (home in Colorado Springs)
Pity of it is, catasstrophic converters are one of the largest automotive frauds ever pulled off on the public....for non existant reasons.....now we can't even get decent OIL anymore....gone well beyond stupid...to the sublime....just ANYTHING to kill off old cars and force sales of more 30,000 dollar POS 'cars' on the public.....
Now they want everyone to buy Hybrid vehicles...and next they'll want us to buy all electric vehicles. HEY WORLD! Wakeup, there is plenty of oil to go around for many years to come. Oh yea, like we're going to really produce more gas with corn? As for automotive emissions; what a load of balogna! It's the same silly effort with the R-12 Freon conversion nonsense.
OK, now that I've ranted on one of my many pet-peevs, I feel much better now.
Drifting
Joined: Jan 2004
Posts: 1,991
Likes: 3
From: Piscataway NJ
It took them 37 years to find out zinc was killing cat. convertors? I think it is Big Brother, along with Green Sleaze way to kill the Old car enthusist hobby. Start buying up the roller blocks.
Le Mans Master
Joined: Mar 2001
Posts: 6,237
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From: Watkinsville, GA and Glen Cove, NY
Don't use Valvo NSL thinking it has any ZDDP. Saw a Virgin analysis on Chevelles and it was not even close to being enough. Even the newer CJ4 diesel oil still has alot of ZDDP, just not quite enough of accepted minimums. Diesel oil also is higher in detergents which may help wash more of the good hings off our lobes. I agree with the Brad Penn and Joe Gibbs.