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Discussion Starter · #1 ·
I've talked to 6 different people, and got 6 different ansers, but all agree not to let it idle at all. I ate two lobes off my cam, and killed a new set of lifters. What rpm should I run it at, and for how long???? I've herd 3500 for an hour, or 1800 for a half an hour, let it cool down and go again. How do the gurus do it on here??? Im going to put the motor in without the d-shaft so it wont kill the pump in the driveway. Im running rotella t 15w40 with a zink additive NOW. Befor just the rotella t, and no additive. Any info would be helpful.
 

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This is just my opinion, others will have their own, but 1500rpm minimum 2000 a little better. Vary it up a little, 1800, 2300, 2000. All you are trying to do is get the lifters spinning in their bores and establish the pattern. 20 minates will do it, probably 15 will do it, but 20 would be safer. The ZDDP or zinc is your best friend. Don't run without it. F1~;)
 

· Boat Nut
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Son of a gun Donny lost some lobes :mad: 1800 rpms for 20 minutes don't shut it don't, even if it runs crappy. You need the oil flow on the cam lobes. Yea the ole Rotella don't have much zinc these days either, good thing you have the additive. Run the additive at each oil change there after, it's like half or quarter of the break in amount. Good luck!
 

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I agree with Factory1 that's how i break in my cams and have been doing it for years, knock on wood haven't lost a cam yet. i usually set it to run at around 2000 to 2300 and occasonally tap it up to 3000 or so. Make sure to run the zinc additive i use comp cams additive most of the time. Just my 2 cents :)hand
 

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The RPM is dual-purpose but mainly for oil-splash onto the cam/lifters.

The ol' truck oil trick doesn't work anymore. Any of the cam-break-in additives should be fine. I haven't heard of any that don't work. I use the GM OES, but my engine builder uses CompCams. I haven't lost ONE cam yet using the GM stuff.

1500 minimum. The old rule is "2000 for 20". I usually vary it from 1500-3000 in 500 rpm steps with a few "wings" to 4000 or so.

I just did a 302 Ford in my '52 convertible. 1500-2500 for 20 minutes and it is just fine. I used the GM stuff in there also.

Use whatever oil you want, that's not the important part. It's getting the zinc in there.

This applies to flat-tappets only. Rollers lifters/cams need no break-in.
 

· Sit N' Spin
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The three motor's I've built with flat tappet cams in them was 2000 RPM for 20 minutes. Once you get the motor to fire for the first time, DO NOT LET IT IDLE!!! Get it up to 2000 RPM IMMEDIATELY upon fire up.

As was mentioned above, vary the RPM from 2000 on up to 4000-4500 in short bursts throughout the 20 minutes. The main objective is for the cam to wear a pattern into the foot of the lifter that makes it spin on the lobe. While it's doing this it needs all the lubrication it can get, so the motor has to run at 2000 to keep the oil pressure up.

Also...you may not want to run a straight weight oil on break in. The multigrade oil will be much thinner and will flow better at cold start, which gets oil to the cam/lifters quicker.

For my motor, I used the Joe Gibbs Performance Break In oil. It's a 15W-50 oil that has the ZDDP already in it...and lots of it. No additive needed.

Change the oil and filter after break in. I recommend Valvoline VR1 racing oil as it has the ZDDP already in it...again no additive needed.

One question I have...

What is your valve spring seat pressure? Open pressure?
 

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Flat tappet cams require the lifters to spin in their bores, otherwise they would just wear grooves in the lifters, and wipe lobes off the cam. The lobes on a flat tappet cam are actually ground with a tiny amount of taper to them which causes the lifter to spin. Think of it like hitting the q-ball on the pool table off center to cause it to spin. Same principal kinda. But the spinning pattern needs to establish on a new cam and lifters, and it takes elevated rpms to do it. Once that has been done, each lifter is mated to it's cam lobe. Tear the motor down and reuse the cam and lifters, you better get each lifter back in the right hole, or you will be replacing them. ZDDP more commonly known as zinc, used to be common in all motor oils, but as the oe's finally went away from flat tappet cams and embraced rollers, the high pressure friction modifier was no longer needed. Hence why flat tappets got a bad rap for a while. The zinc was removed from oils, flat tappets started biting the dust, and everyone looked at the cam manufacturers thinking they were making bogus products. It was finally realized the missing zinc was the cause. The Valvoline VR1 is a really good oil with zinc. There are others, do your homework, decide what you are happy paying for oil. Good luck with the new cam, F1~
 

· steelcomp was here
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x2 (by 1 quart)

2000rpm for 20 minutes should work

I would use something else other than Rotela T ... Valvoline VR1 is much better

also I would use Torco's MPZ assembly lube on the bearings and cam lobes
Bearings, yes, but on cam lobes and lifters I use a good moly assy lube (on the faces), and I use MPZ in the lifter bores and on the sides of the lifters. I love MPZ, just not in high pressure break in apps like flat tappets. As usual, though, JMO.

On cam break in, one thing you need to do is make sure when you're ready to start the engine, it fires IMMEDIATELY! I don't care what you put on a cam, if you have to sit there and crank and crank to get it started, you'll ruin the cam. Make sure your timimg is close enough to run. Leave the hold down clamp lose enough so you can turn the dist if need be. Prime the carbs, turn the idle screw up, water hooked up, battery charged... double check everything and don't get in a hurry. If you have dual valve springs, remove the inners for break in. (Dual meaning two springs, not a single spring and a dampener.) Be ready to have the engine run at 2000 rpm for at least 15 min, the longer the better before you ever let it idle. It doesn't hurt to vary the rpm eiether, but gunning it 'cause it sounds cool, isn't cool (IMO). While it's idling you can also set the timing, check for leaks, etc.
 

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Molybdenum disulphide is the toughest friction modifier you can add to an engine or gearbox. It is also an EP lubricant and is used by engine and gear manufacturers during assembly.

As for ZDDP, this additive doesn't work until you have lost the oil film. By then, friction has risen to such a high level that the heat produced activates the zinc in the ZDDP. The zinc is NOT an EP lubricant. Do NOT rely on ZDDP to sustain your cam and lifter faces.

Also, ZDDP is often found on lifter faces in high amounts...undesirable.

Stick with moly. The bearings, rings and exhaust valve guides and stems will run cooler and you engine seals will last longer. Moly helps to reduce parasitic HP loss. Some engine tuners say they gain 5% HP from the use of moly.

You can reduce oil temperatures by as much as 10F. just by adding moly.

I would start with a good oil for breakin and ad moly to about 15% by volume. I'll not make an oil recommendation because I have no idea how your engine is set up, piston speed, piston FPM, clearances, combustion chamber pressures, etc. The Rotella sounds OK.....which VIS are you using? Don't be afraid to run it at 4000 RPM for short periods after the engine reaches running temperature.

Also, make sure the oil is not entrained with air. After a short run, shut down and check the dipstick for air/oil. I have always preferred an oil window in the pan to a dipstick.

Also, don't forget, moly in the V-drive can help as well. Moly can quiet a noisy gear set immediately. Also, the moly helps seals last longer.

Also, remember, you likely going to use some oil for the first 20 hours of operation. This is not a bad thing. Just keep an eye on oil temperatures and level.
 

· E-7 Sheepdog (ret)
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If you have 3-piece springs REMOVE THE INNER SPRINGS to reduce pressure on the lifters.

Broke in my flat tappet cam setup in 2004 on straight synthetic Castrol Syntech 20w-50, not an additive one (except the cam lube Isky supplied), and only used 5 quarts of it.

Left center springs out for about 8 hours of boating.
My full spring set pulls 150# closed.

2,000RPM for 20 minuites, I ran closer to 2500 for nearly 30 minuites.
 

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I've talked to 6 different people, and got 6 different ansers, but all agree not to let it idle at all. I ate two lobes off my cam, and killed a new set of lifters. What rpm should I run it at, and for how long???? I've herd 3500 for an hour, or 1800 for a half an hour, let it cool down and go again. How do the gurus do it on here??? Im going to put the motor in without the d-shaft so it wont kill the pump in the driveway. Im running rotella t 15w40 with a zink additive NOW. Befor just the rotella t, and no additive. Any info would be helpful.
hyd roller w/ lifters $75.00

http://www.performanceboats.com//showthread.php?t=44616

it's not worth the time or money to put in flat/hyd cam back in. time and parts w/labor and it may happen again no way! :D
 

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I've talked to 6 different people, and got 6 different ansers, but all agree not to let it idle at all. I ate two lobes off my cam, and killed a new set of lifters. What rpm should I run it at, and for how long???? I've herd 3500 for an hour, or 1800 for a half an hour, let it cool down and go again. How do the gurus do it on here??? Im going to put the motor in without the d-shaft so it wont kill the pump in the driveway. Im running rotella t 15w40 with a zink additive NOW. Befor just the rotella t, and no additive. Any info would be helpful.
Hell, there is about 10 or more answers. One or two are way off base IMO.
Wags
 

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Discussion Starter · #18 ·
WTF IS GOING ON IN MY MOTOR!!!!!!!!!!! This time it took out the whole cam!!!! I used the ARP molly lube on the lobes,the supplyed lube from comp on the the berrings, then dumped the rest on top of the cam, im running new k-motion stock springs, and i put a bottle of additive in the oil as well. rotella-t 15w40 1/4 turn on the polly lock. I ran it at 2200 for 1/2 an hour. then put the driveshaft in and took it to the river. it didnt sound bad until I went to take off, then it sounded like it weas going to rattle appart. I stoped reran the valves and it was better. went for a little rideit wouldnt go over 4300 and i took it out and went home pulled the intake off and cried. Only two lifters will come out, the rest have a bur on them and wont come out. I put oil in the pan and spun the oil pump befor i put the lifters in and oil came out of all the lifter bores. At the time of assembly it was fine. Now i dont know until i pull the bitch appat.
 

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sounds like the lifters are sticking in the bores,making the cam go down.only way to fix this is roller or have the lifter bores sleeved,core shift in the block.

sorry this is happening.:|err
 

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I know it's after the fact now, but when you put the lifters in did they go in easy? I'd stick a new lifter in each bore, once you get the old ones out, and see if it spins easily, as well as moves up and down.
 
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