New camshaft break-in procedure & oil additive.

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Not sure where to post this question.
I just installed a new Hamilton 188/220 flat tappet cam in my 1999 Dodge Cummins Diesel.
They are very specific about the break-in procedure, add 1 bottle of ZDDP to the engine oil, start it and run it at 2000 rpm for 20 minutes, and I (think) understand why.
Correct me if I'm wrong;
1) 2000 rpm’s which is 1000 cam rpm is needed to ensure there is sufficient oil throw off from the crank to properly lubricate the cam lifter interface and,
2) 1000 cam rpm’s is necessary to enable a hydrodynamic fluid film to be established between the cam and lifter interface which minimizes contact allowing a slow controlled process where high spots are leveled and which also allows the surfaces to become work hardened.
What I would like to know is;
Does the manufacture perform this operation?
If not then why don't cams fail in new engines? I realize roller cams don’t require this process.
Back in the 60's & 70's all cams were flat and I'm sure they didn't run every engine 20 minutes for this break-in process.
Why didn't cams fail back then at a high rate?
I’m aware that today’s oils are lacking in anti-wear additives and are the cause of premature cam failures.
Back in 1990 when I bought my first new Dodge CTD I believe they gave each engine a hot run to verify all systems GO.
Do the still do this?
Do OEM’s spike the factory oil fill with ZDDP?

Thanks
Ducati996
 
New cars are almost always "broken in" at the factory (to some degree). They will typically throw them on a dyno and run a series of tests. Some manufacturers, however, still put special break-in oils in the sump and/or have special requirements for the first oil change. BMW, for example, puts a 5w30 conventional oil in their M cars for the first 1200 miles (along with a low redline) and then requires you to visit the dealer to have it changed out. Honda also has a special high-moly break-in oil.

Also, modern mass-engine building is far better than the stuff 50 years ago. The whole concept of break-in is not what it used to be. There are literally millions of modern cars that had no break-in procedure that make it well past 100k, 200k, 300k.
 
The cam manufacturers use a machine to break the cam in before delivery.
I can remember a few engines that the cams were not broken in on and had very early cam failures.
Some engines are hot fired, some are cold run sans plugs before they get installed.

They use a machine like this..

http://www.camresearchcorp.com/
 
Back in the 60's I remember new engines being run NOT under their own power, but being driven.
Later, they would be further run-in under their own power.
 
Originally Posted By: Ducati996

I’m aware that today’s oils are lacking in anti-wear additives and are the cause of premature cam failures.


Actually, that's not really true. While some PCMO's may have slightly lower levels of ZDDP than they did "back in the day", we've seen VOA's of oil from that era and it really wasn't the hot stuff, heavily laden with ZDDP many think it was. The bigger issue is cheap Chinese cam cores and sub-par quality of the shafts themselves with poor hardening...etc.

Also, stock camshafts are much milder than many of the "wild" aftermarket bump-sticks, which means they are less prone to failure due to poor break-in procedures in the first place.

GM had a rash of "soft" camshafts in the 80's IIRC that resulted in many of them "going flat", and that was with "back in the day" oils to boot
wink.gif
 
^^^Exactly. Teething issues with roller valvetrains were common in the early days.

Cam quality is very suspect in the aftermarket. Me and my BIL have rejected many a camshaft due to all sorts of poor quality things.
 
I worked in transmission engineering on the development of the US Armies Bradley Fighting Vehicle Transmission so I’m interested in the actual dynamics of the process.
I’ve seen, learned and experienced more than many could imagine but this particular design/process was not utilized.
I was hoping for a Camshaft Engineer’s explanation of the actual mechanics involved in the break-in process.
Videos on how to properly break-in a cam are nice and emphases the importance of the procedure but I’m always looking for the Nitti gritty minute details.
I’ve never been one to only accept a statement (this is how it’s done) I’m a detail man.

Thanks
Ducati996
 
Comp Cams has a fantastic tech line. I used to be able to call Crane and speak to a real engineer.

I suggest you consider the telephone...
 
SRT8
I went to Comp Cams website and it is quite informative but I didn’t find the answer I was looking for so I posted my question there also.
No response yet.
Hopefully someone will respond to my post so we can all learn about the very important process of cam break-in.
How an engine is operated the first 20 to 30 minutes determines the overall performance & life expectancy.
Thanks
Ducati996
 
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