Camshaft Failures

[dwg86]

Is there any certain brand of camshaft that has been failing? The last cam I used was a Reed cam(401 in my 79 cj5), and had no problems with it. I am going to be building a stroker 4.0 for my 2003 TJ, and I have a spare 401 in the garage that will also be getting a rebuild sometime soon (I'm thinking stroker... don't know what I am going to pit it in yet). I want to stay away from any cam manufacturer that has been prone to failure.

[jeep_man_401]

It is some peoples opinion that its the oil that is causing the camshaft failures nowdays. The oil has been reformulated, taking out some or all the zinc and other high pressure additives.

Seems like a "hidden" way to get all the old cars off the road by slowly killing the engines and replacing them with the new roller cam and overhead cam models.

Hot Rod did a good write-up on it awhile back. AMC's aren't the only ones dealing with these failures.

Lots of moly lube and some Crane Cams break-in additive...

[jeepsr4ever]

Cam break in requires zinc phosphates and at least 10 points of hardness on the rockwell scale between the camshaft and lifters. Next you will need to break in the camshaft right allowing it to find its wear pattern without gaulling and this is where the rpm and the zinc come into play. 2000-2500rpm for at least 10mns used to be the norm for breaking in a camshaft. More and more carefully break in is required with federal regulations pending on phosphates (which steal calcium from our bloodstream/bones). Many oil companies do not add this expensive additive to their oil anymore. In fact unless it is listed their are very few oils that contain this additive anymore. Even some diesel oils are cutting the additive packages down eliminating zinc phosphates so even a diesel oil may not be safe for cam break in. I would use a matched set of camshaft and lifters. Failures occur when the cam is made by company X and the lifter are made by company Y and the hardness values are not kept in check.

[Mcktiger74cj5]

im going to use vavoline30 wt. to break in the cam. the rotella 15/40 for the engine 500 miles. then vavoline 10/30. sound right?

[Soylent_Green]

Something to check out: The valvoline Racing oils have a very high zinc content. It helps to raise the 'flash point' of the oil, that is, the temp. at which the oil vaporizes into gas on hot internal engine components.

[AMX69PHATTY]

Cam brand I do not believe was what caused my lobe failure.
It was an reground stock AMC cam done 20+ years ago.
Most likely it was the builder, namely me, who didn't keep the
original good lifters that had been on this cam in order during disassembly,
so used new lifters on an old cam and lost a lobe.
They other 15 lifters and lobes look fine though.
I also did not remove inner valve spring for break-in.
Seat pressure was stock +30 @ #120 & ~#315 open .520.

[fifesjeep]

I always use Valvoline 20w50 Racing Oil for cam break-in... And Haven't had a problem yet.