Going Easy After Engine Rebuild?

[Jake1798]

Hey guys (and girls),

I have heard two different things when it comes to how you should treat your engine after a fresh rebuild. Some people say to baby it for the first five hundred miles or so..take it easy. Others say to drive it the way you will be driving it. Who is right??

-Jake

 

[Sensei]

You want to seat the rings right away by accelerating full throttle from 30 mph to 50 mph then coasting back down to 30 about 10 or 12 times. This hard mid-range workout will establish oil control and have you set for the rest of your brake in. For the first few hundred miles while you still have assembly lube and metal particles floating around in your oil, you don't want to accelerate hard from a stop, or check out your top end speed (stay within the speed limit and you should be okay). After that, as long as everything is working right (temp, oil pressure, etc.), have at it! God bless, Sensei

 

[GerryLP]

Hey guys (and girls),

I have heard two different things when it comes to how you should treat your engine after a fresh rebuild. Some people say to baby it for the first five hundred miles or so..take it easy. Others say to drive it the way you will be driving it. Who is right??

-Jake

It probably won't make a difference, for it all depends on the type of stresses that the engine will undergo while in use. What really will matter will be the components used and quality controls applied to ensure that the required clearances are achieved.

I say build it for the way you will be driving it.

You see, easy driving results on lower stress loads being applied to the engine components. Hard or race-type driving results on higher stress loads that the engine will encounter, so the best one can do is pursuit a two-fold goal:

1) select suitable component features for the type of driving desired. For example, forged components for a drag-racing engine. Use high-flowing cylinder heads. If just cruising, then perhaps opt for a torque-profiled cam over a horsepower-profiled cam.

2) maintain high quality controls across tolerances. For example, machine cylinder bores with torque plates installed. Blueprinting of components. Stress relieving of metals in critical areas.

If one aims for these two goals, then one most likely will have built-in a certain measure of reliability that will certainly result in personal satisfaction.

GerryLP:cool

 

[Jack]

You want to seat the rings right away by accelerating full throttle from 30 mph to 50 mph then coasting back down to 30 about 10 or 12 times. This hard mid-range workout will establish oil control and have you set for the rest of your brake in. For the first few hundred miles while you still have assembly lube and metal particles floating around in your oil, you don't want to accelerate hard from a stop, or check out your top end speed (stay within the speed limit and you should be okay). After that, as long as everything is working right (temp, oil pressure, etc.), have at it! God bless, Sensei

I agree ... seating rings is important ... this method is recommended. I also agree you don't want to be too hard on the motor until you've gotten most of the breakin bits outta there. Suggest O&F change immediately after 20-30min cam breakin, then again at 100miles, again at 500more ... then let her rip.
JACK:gap

 

[lightingrod]

What Jack said!

Al