how to break in rebuilt motor

[allenweeks]

i got a 90 horse evinrude and would like to know how to properly break it in. it has 2 new pistons and new rings all around. on cylinder was bored and the other honed. the mechanic has already done the low speed break in. he tells me to now run 20 gallons with double tcw at 1/2 to 3/4 throttle. then run 20 gallons with double tcw at 3/4 to full throttle. does this sound about right? i just want second opinions being i jsut spent so much dough on this rebuild and want it to last a long long time. thanks

 

[Rick.]

Re: how to break in rebuilt motor

I see no reason to run a 25/1 mix but if he is going to warrantee the motor you might as well do what he says. As far as the throttle position I think it is better for the motor to vary the speed lots and very little of it at WOT but yet some WOT. You better check with him again to make sure you understand him correctly. Rick

 

[allenweeks]

Re: how to break in rebuilt motor

yes that what i mean, he tells me to run up and down the lake,moving back and forth from 1/2-3/4 throttle. he said back and worth so much your wrist hurts.. lol he gave me a 90 warranty

 

[iwombat]

Re: how to break in rebuilt motor

Standard break-in procedure is double-oil mix.

You should do what he asks or risk your warranty.

 

[mrimike]

Re: how to break in rebuilt motor

its usually most impt to vary the throttle so the rings seat properly
dont be afraid to punch it every now and then to clear it out ... better bring some extra plugs with you b/c you will foul em out.

that break in sounds a little excessive..
but i guess better safe than sorry.


run it for a while.. then let it cool and then run again.

 

[allenweeks]

Re: how to break in rebuilt motor

by all means i have followed instructions from him. i was just getting 2nd opinions.

 

[Faztbullet]

Re: how to break in rebuilt motor

That a lot of excessive oil and time. Here is link to how should be broken in.
http://mar-fab.com/BREAK-IN-PROCEDURE.pdf

 

[Titanium48]

Re: how to break in rebuilt motor

150 L (40 gallons) of 25:1 mix is probably just about right for a 10 hour break in period at an average of 1/2 of full power.

 

[allenweeks]

Re: how to break in rebuilt motor

seems like its about right then. thats what he told me, vary speeds and putting heat to the engine and backing off. getting the rings to seat right and the pistons to grow with the cylinders, thanks everyone.