FITO

i just got a hudy break-in bench and i would like to know what are some of technics some of you guys are using to properly break-in a engine in a bench thanks

captian

most important take you time heat cycle and 4 stroke

pepsidawg

iTrader: (1)

KEEP OR PUT HEAT IN THE MOTOR! This cannot be expressed enough! Wrap the motor with foil. Block air from prop from getting to motor. Preheat motor with heat gun(it is your friend) to at least 200 F., 230 or 240 is better. With rich breakin settings you will have to hold the heat gun on head to maintain the temp. Use a temp gun. Just don't let it get too cool when its running. The motor gets to much abuse when its in the car and there is no sence in abusing it on the bench, just keep that thing hot and rich on the bench. When you put it in the car you might still need foil on head to maintain temp, just don't run it cold(below 200 F.) Maintaining temp in the car will be easier because you will start to lean it and that helps build temp.

new3

just remeber one thing when you break in a motor they are all different and each motor requires a different breakin techneque

casimirsa

I have use a few makes and models of .12 and .21 over the the years and have used the method that pepsidawg describes in his post.

I would like to add that it is necessary to also block airflow over the crankcase. Doing that makes life much easier to control the temperatures!

Secondly only heat up the motor on the cooling ahead allowing time for the heat to be drawn into the p/s and crank case.

The reason for this is that if you heat the motor from the sides you never will get an even expansion of the p/s causing uneven wear.

YLLIB

iTrader: (1)

I break the motor at an idle for one tank @ 180-200 Deg. piston BDC and let cool for 10 min. Then I do two straight tanks at an idle 190-200 Deg, and let cool for 15 min, piston BDC. Then two more straight tanks @ 200-220 Deg, and let cool for 15 min then on the track for a tank around at 200-220 for a tank and then let her rip. Also when breaking in the engine I do clear it out a couple times a tank at 4 stroke level, just to clear it. I also made a sleeve that wraps around the head during break in for even temp, it is made from race car exhaust insulating wrap, it made to wrap headers, and it works awesome and very temperature control around the engine body nicely.



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