Flat tappet cam break in

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Originally Posted By: Chris142
Non stop for 30 minutes unless an emergency like an oil leak or overheat happens.



Exactly the answer to what I was wondering.


I was reading procedures for crate engines and was unsure

Thanks Chris142.
 
Thanks FordCapriDriver

cool, demarpaint. All at once was what I was wondering.

gotcha, ShotGun429

DoubleWasp.....no idleing

Trav, yes it said to prime the oiling system. Yes I think it said exactly 2000-2500rpm

The Eric, good to know

Rat407, maybe you did it correctly without knowing or trying.???

ARCOgraphite, good to hear from ya....I was just reading JEGS advertised engine specs and spec sheets

BrocLuno, thanks for the lesson and insight.


MarkM66, do it right the first time is so much more fun isn't it. Too sad many times we have to learn the hard way AND do it over and over...

Linctex, "oil slings off the crank at different angles at different RPM" thank you so much for that statement. It is good information to have at hand.

Bgallagher, that is what it said. I just didn't know if it was all at once or not.

funflyer, I think 5w-30 or 10w-30 is the preferred break-in
 
How rare is it that someone actually acknowledges those who took their time to help...

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mjoekingz28
 
First time Ramblejam that I used my iPad and desktop at the same time.

I used the ipad to scan through the posts while using the desktop to type.

I was hoping to get every poster in, but the second page kind of slacked off.
 
Originally Posted by mjoekingz28
They say to keep the rpms elevated for about thirty minutes. Do they mean as soon as you fire your rebuilt or crate engine for the first time that you need to sit there for half an hour with your foot on the pedal?



Or could you run it for five or ten minutes here and there until you reach 30 minutes total?


Summit Racing: https://static.summitracing.com/global/images/instructions/tfs_cam_install.pdf
"Start the engine and immediately bring to 3,000 rpm. Timing should be adjusted, as closely as possible, to reduce excessive heat or load during break-in. Get the engine running fairly smoothly and vary the engine speed from 1500-3000 RPM in a slow, to moderate, acceleration/deceleration cycle. During this time, be sure to check for any leaks and check out any unusual noises. If something doesn't sound right, shut the engine off and check out the source of the noise. Upon restart, resume the high idle speed cycling. Continue the varying "break-in" speed for 20 - 30 minutes. This is necessary to provide proper lifter rotation to properly mate each lifter to its lobe. Should the engine need to be shut down for any reason, upon re-start it should be immediately brought back to 3000 rpm and the break-in continued for a total run time of 20 - 30 minutes."

Crower: https://www.crower.com/media/pdf/cam_book.pdf
"Do not idle engine under 2000 RPM for the first 30 minutes."

Comp Cams: http://www.compcams.com/Instructions/Files/COMP4-115.pdf
"As soon as the engine fires, bring the RPM up to 2000 to 2500 during the first 30 minutes of operation. Slower engine speeds will not supply the camshaft with an adequate amount of oil for the break-in period. The engine RPM may be varied periodically from 2000 to 2500 to direct oil splash to different areas of the camshaft."

There's a great deal of consistency there. There are also other recommendations with regard to type of oil, ZDDP levels, reduced spring pressures, etc.
 
I have broken in a number of flat tappet cams over the years. If I ever pull apart my 68 Vette (original L36 427) or 65 4-4-2 (original 400) I will stab a roller.
Having said that, I can add a few tips to the above good advice...

Set your timing before firing engine. I set damper to 6* BTDC (or a little more), hook up timing light, turn on key and slowly rotate distributor.
When light flashes, snug down distributor.
Prime that carb.
This will ensure she fires right away.
Moderate timing keeps down heat; do not run retarded timing!

Break in generates a ton of heat.
Make sure the garage doors are open. Put a window fan in front of the radiator for additional air flow.

Firing a motor for the first time is soooo exciting.
 
I use Driven BR30 break-in oil with a Fram Ultra filter. I start it up, idle for just 10 seconds or so to make sure I have good oil pressure, fuel pressure, etc... and then go to 2000 rpm for 20 minutes. After that, I take it to the track and hammer down. I go 15-20 1/4 mile passes or 25-30 laps around the dirt oval. Then I replace the filter (not the oil), top off the oil, and go for 20-30 more 1/4 mile passes or 30-50 more laps. Then I dump the break-in oil and filter, and use the preferred oil and filter from then on.

For a street driven engine, the process is the same except instead of the track, I go out to a rural road and vary the load on the engine. I'll start at 20 mph in 2nd, hammer the throttle all the way to redline, and then coast back down to 20 mph. I'll do that 15-20 times, change the filter, top off the oil, and go 150-250 miles. Change the break-in oil and filter, and use preferred oil and filter from then on.

The worst thing you can do to a fresh engine is crank it up and let it idle.
 
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