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Proper way to break in a engine?

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Old 02-21-2010, 07:42 PM
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Default Proper way to break in a engine?

So i am currently in the process of rebuilding my engine. I am completely putting in all new parts (lifters, pistons, crank and cam etc.) So whats the best way of breaking in a new engine? I have heard so many different ways, i was just wondering what way is best? any ideas? thanks!
Old 02-21-2010, 07:43 PM
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The way i always broke in my mustangs was drive it like i stole it as soon as i pulled out of the shop.........
Old 02-21-2010, 08:38 PM
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if your installing a new cam you need to run it at 2000 rpm's for 20 mins, change the oil, then after that drive the hell out of it to seat the rings, run cheap oil for the first 500 miles then switch to whatever you like
Old 02-21-2010, 08:44 PM
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really? i heard u drive like under 55 and stuff goin easy on it.......
Old 02-21-2010, 08:55 PM
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Originally Posted by maverickdan
if your installing a new cam you need to run it at 2000 rpm's for 20 mins, change the oil, then after that drive the hell out of it to seat the rings, run cheap oil for the first 500 miles then switch to whatever you like

x2 but dont get caught when you drive like hell.
Old 02-21-2010, 09:06 PM
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I have always just ran it at a high idle like mentioned above and then drove it after all was checked. Just drive it normally.
Old 02-21-2010, 10:29 PM
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so with the new cam i need to keep it above 2000 rpms for 20 minutes?!? why is that?
Old 02-21-2010, 10:36 PM
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JUMP IT
Old 02-21-2010, 11:01 PM
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Originally Posted by goneboating06
so with the new cam i need to keep it above 2000 rpms for 20 minutes?!? why is that?
it seats the lifters to the came and gets the oil flowing

one good thing to do is keep the valve cover of tell you fill the oil through the top of the head
it lets the oil run over all the parts before going into the pan
Old 02-21-2010, 11:05 PM
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oh, ok thats what i was thinking. Thats actually a good idea, i haven't thought of doing that. Thanks!
Old 02-22-2010, 01:14 AM
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I've been told all of these methods. The one that I use is drive it normal to YOUR driving habits. If it's a car your always beating on, beat it from the start. If it's jeep that you dd and cruise in, cruise in it.
Old 02-22-2010, 02:19 AM
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I have always held it close to the 2000 rpm mark, but never holding it at a constant rpm. Slight rpm jumps 1800-2000 rpm. This helps the rings mate properly with the walls, and also the rpm helps the cam and lifters get mated together. And just normal 10/30 oil with crane cams cam break in additive or something similar. Do that for 20 minutes, change oil and filter. Let it cool back down, then start it up again and start driving normally. Another oil change in about 200 kms, then after that I just drive it how I normally drive.
Old 02-22-2010, 07:22 AM
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When i put my Ford 302 together the break in procedure written in the book that came with my rings stated. 1-2K miles or a night at the track for proper ring break in.........
Old 02-22-2010, 08:01 AM
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one good thing to do is keep the valve cover of tell you fill the oil through the top of the head
]

do this when you prime your oil pump, make sure you are getting even flow across the top end if you have debris in the oil passages nows the time to find out not when you start it up.
Old 02-22-2010, 08:26 AM
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all right, thanks for all the help!


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