Technical What would happen if you simply didn’t break in a flat tappet cam?

I think difference would be is amount of oil with a sliding action vs rolling. Also, rollers don’t (I think) need to have a wear into them per lobe.
I/e if you swap around roller lifters to different holes, no harm can occur.

 

I have had two expensive cam failures. From then on, I won’t buy an engine that has not been built and broken in by a professional.

 

The metallurgy thing is a real deal. Back in the '90s Crane had at least one batch (maybe more) of soft lifters. I trashed a set on my own 355 within the first 500 miles and a couple of other engines. The cams all lived fine (mine has 150k+ on it today). When I was dealing with my own and a couple of others (all at the same time) and at my wits end a friend @ Erson cams told me what was going on and sent a set of Erson lifters to try, I am still running them on my Crane cam.

This is not to bad mouth Crane cams I still run them.

 

Man! That is a huge blog….lots of info! Seems to be a smart man! I was with him on most stuff , till he got to oil mesh air filters! But his test did show something……..there is a lot of differences in oil, according to his test! Good read…..long and a lot of subjects other than oil!






Bones

 

Ditto for me, and the hot rod generation before me that taught me that method. Never had a cam go flat, but
never tried it any other way. Bob

 

I ran in the most recent cam as directed, afterwards realized I forgot to put the break in lube in!!

Think I should break it in again with the lube?

 

With the slightly convex face of the flat tappet and the slightly tapered lobe on the camshaft, there's a whole lot of forces at work trying to wipe away as much lubrication as possible where the two parts make contact. But it's kind of a necessary evil in order make the lifter rotate during operation so all the wear doesn't happen on just one area of the lifter face. So you splash a little oil on that area to help it live longer. (There's a very similar affect that takes place between the teeth of a hypoid ring and pinion gear set. Because of this "wiping" effect you need to use the special hypoid rated gear lube.)

A roller lifter however has a larger contact area across the lobe of the cam. There's much less of an attempt being made to completely wipe away all the oil between the two surfaces. So they can hold up pretty well with less splash oil being thrown around in the crankcase. And there's no need (or desire) for the lifters to rotate when operating.

 

But the only oil that is lubricating the axle of the roller is from splash, correct? It seems like that would be a harder area to get oil to than the surface of the cam lobe. I'll probably stick with my flat tappet lifters, I've yet to have a problem. I'm somewhat of a traditionalist lol.

 

Hey, Blues;
Very good write-up.
Marcus...

 

I was taught to use moly lube on my cams. A lot of moly lube. It would stick around in the oil for a while. I still use cheap oil on the break in, although I do add a break in additive nowadays

 

Me too !

 

I wasn't sure about this myself. But it appears that at least some roller lifters pressure feed oil to the bearings on the roller axle.
This diagram seems to be of a Comp Cams Sportsman solid roller lifter, as best as I can tell.

 

There is one other factor that I have not heard mentioned. How long has the engine sat around before being started and broken in? Some lubes dry out, some will drip off, etc. And priming the pump does nothing to put oil on the lobes prior to startup.

I always wait and install the intake after I've put the engine in the car and am ready to start it up. I pour the oil in over the camshaft, install the intake, etc. And crank the engine as soon as I can. I also use oil with zinc in it. No problems here but I have not installed any radical camshafts, either.

To me, this approach makes best sense. A friend recently flattened a lobe on the cam of an engine that was built 2 years prior. They primed the oil pump but the stock cam failed due to lube problems on start upIf He agreed that if he had followed my approach, he would likely not had this problem.

 

Certain lubes once applied to metal can not be removed by any other means than grinding or burning.
They have an attraction at the molecular level.

 

I was looking into this a while back, here's a reply that came up in another forum.

"There wasn't any cam break-in process at Flint V-8 or at Tonawanda. The engine ran for about 30 seconds in the hot-test stand to check for noises/leaks and to set the timing, and the next time it ran was when it was driven off the end of the Final Line at the car assembly plant.

All small-blocks (from 2-barrels to solid-lifter 4-barrels) used the same mild valve springs, and all factory cams had the lobes Parkerized to better retain an oil film; aftermarket flat-tappet cams without Parkerized lobes have a high failure rate without a specific cam break-in procedure and break-in additives.

Most modern "roller-everything" engines aren't run at all at the engine plants - they're "cold-tested" on computerized test stands at low rpm, driven by an electric motor, with 20-30 electronic pressure/vacuum/position/torque sensors logging data. These setups can not only tell you there's a piece of dirt in a rod or main bearing, they can tell you which one, AND whether it's in the upper or lower bearing shell. Great technology!

Regards, John

 

If you are talking about cam break-in....
Yes, since surface is somewhat rough on the micro level after the grind and polish. Also means new or properly refaced lifters at the same time.
Have to do the break-in just like it was all new.

If you mean refaced lifters needing to go back on their original cam lobe after a cam regrind....then no, since surfaces are fresh and no wear mating has been established yet.

 

OK, I've got another "enlighten me" question...
With all the examples of cam and lifter wear, I haven't seen mention of wear on the lifter O.D. or lifter bore in the block. If lifters are rotating, shouldn't there be wear? Granted, the friction is lower, however side loading is pretty great which should make the bores egg-shaped.
I tend to think the culprits are metallurgy and heat treat at the cam/lifter interface.

 

The author, 540 Rat, has been pounded on forums populated by OEM engineers , cam grinders and pro engine builders who consider his oil tests non relevant....






Bones[/QUOTE]

 

[/QUOTE]
Thanks for replying. I read this blog with an open , but cautious mind. The author spend a huge number of pages patting himself on the back and defending himself. That was my first alarm. But he seemed to make sense. One thing that I took from this long read and I didn’t read every word, was that his test results on oil varied widely! I don’t know exactly what his test is, but any test of many oils that produces a huge variation in oil proves at least one thing……different brands of oils are different! He seemed to put importance on a number that was expressed in psi.
I caught one odd thing was that he said many times to never use an additive and then when on to test Prolong and give high marks on some oils.
I know all the degreed folks say “ never use any additive” but I have solved many problems with a special additive I use. The last was solving a big block pro charged Chevy that was eating pushrods in a Street Outlaw drag car at the Tulsa Shoot out. It worked so good we won the meet!
I always read these things, because my brain says” no additive “ but my eyes see results!
But he completely lost me with his endorsement of oil mesh air filters! Just my thoughts.










Bones

 

Not breaking in a cam ?





oh the humanity

 

As I recall, and correct me if I'm wrong, but I recall the test he uses he doesn't specify what it is, how it is run, no information about it at all. Just that according to him it's the best test in the world, and only he can do it, yadda, yaddam yadda. The lubricants world is full of snake oil salesman, and everything from this guy comes off just like them.[/QUOTE]

 

Anybody have a picture of this "Parkerized" ? I think that's what's on my lobe's ?

 

He used the "scar" test....More or less a sharp object is dragged against a rotating wheel......Probably better descriptions on the Internet....A more realistic test would be in a running engine ,but that would take way too much time and money...

 

One legend around here used to break his engines in on the trailer heading out to Detroit Dragway…granted this was in the 60’s, but he was a King out there and couldn’t miss a meet..said he’d get the motor ready to fire, hit it, keep the RPM’s up, get it on the trailer, check for leaks, tighten the throttle to keep it in the 2500 RPM range, close the hood, and drive the truck down to that track, drain the oil, change it and the filter, and in his words “run the piss outta it”

 

As I recall, and correct me if I'm wrong, but I recall the test he uses he doesn't specify what it is, how it is run, no information about it at all. Just that according to him it's the best test in the world, and only he can do it, yadda, yaddam yadda. The lubricants world is full of snake oil salesman, and everything from this guy comes off just like them.[/QUOTE]

Speaking tests and since you’ve been in the business for some time. Have you ever heard of “4 ball wear” test? I just remembered way back in my AOL days someone touting this test. The discussions weren’t about cam failures back then, but rotating assembly wear.

 

When I fired up the 235 for the first time in 1990 I do not think I did the break in,the junk radiator I was trying to use caused so much problems it could not run any longer then 10 minutes and no problem with the cam.

 

As I recall, and correct me if I'm wrong, but I recall the test he uses he doesn't specify what it is, how it is run, no information about it at all. Just that according to him it's the best test in the world, and only he can do it, yadda, yaddam yadda. The lubricants world is full of snake oil salesman, and everything from this guy comes off just like them.[/QUOTE]
Well I thought he was a little squirrely. And had a poor attitude.
I know we have had some good discussions on oils and additives. But , yet again I have solved a problem with my go to additive. That big block pro charged Chevy was eating one or two push rods every pass! We changed nothing other than adding my additive and have not lost a push rod since!
So…. I hope you can appreciate my dilemma!








Bones

 

Well I thought he was a little squirrely. And had a poor attitude.
I know we have had some good discussions on oils and additives. But , yet again I have solved a problem with my go to additive. That big block pro charged Chevy was eating one or two push rods every pass! We changed nothing other than adding my additive and have not lost a push rod since!
So…. I hope you can appreciate my dilemma!








Bones[/QUOTE]


SO what's your additive?

 

Speaking tests and since you’ve been in the business for some time. Have you ever heard of “4 ball wear” test? I just remembered way back in my AOL days someone touting this test. The discussions weren’t about cam failures back then, but rotating assembly wear.[/QUOTE]
Yes, there are at least 2 tests using the 4-Ball arrangement, the 4-Ball wear test and the 4-Ball Weld test. Both tests use 3 balls locked in a device and held stationary and packed with the lubricant to be tested, either oil or grease, then a 4th ball is placed on top of the other 3. In the 4-Ball wear test a specified load is placed on the 4th ball and it is rotated for a specified amount of time, then it is removed and the scar that is developed is measured and reported in millimeters. The smaller the wear scar the better the anti-wear performance of the lubricant. The 4-Ball Weld test is very similar, the 4 balls are arranged in the same way, but the load placed on the 4th ball is gradually increased until they all weld together. The point where they well is reported in kg's, and the higher the number, the better the protection against wear that is provided by the lubricant. While these tests are used for oils, they are more often used to gauge the performance of greases. The test provides much more objective results than the Timken OK load test, another type of test where a wear scar is generated by gradually increasing the load until the test operator determines it has reached a point of failure, then the OK load is the last previous load achieved without failure, hence the "OK".

And as I recall, the guy with the oil blog says the test he uses is neither the 4-Ball test or the Timken OK load test.

There's also a Falex test device that is commonly used by guys that go around to different shops to demonstrate how good their lubricants are. We like to call them the "dog & pony shows" (the lubes business has a ton of 'em). But again, the oil blog guy says it's not a Falex machine. Who knows? It's a secret.