How should I break in the engine

Deleted User · Post by **Deleted User** » Wed Dec 07, 2005 10:32 pm

Are there any recommendations as to how I should break in my 1980 Spitfire, I just rebuilt the entire engine and want to know the best way to break it in.

Thanks

grasscutter97 · Post by **grasscutter97** » Thu Dec 08, 2005 11:05 pm

There are only 2 things I can remember about break in:

1-mix oil a little thicker (don't get crazy), but if you are running 50/1 (which most guys run, using a good synthetic oil), then bump it thicker to 40/1 for the first tank.

2-don't run a full throttle for first 50 miles.

after that...crank it open and have fun.

tipitup · Post by **tipitup** » Fri Dec 09, 2005 12:55 am

I'd say don't break it if you just fixed it, then you would only have to fix it again. LOL

81spitfire · Post by **81spitfire** » Fri Dec 09, 2005 1:09 am

go easy on it for the first tank then ride it like you stole it. oh and mix just a little richer on the oil for the first run.

Deleted User · Post by **Deleted User** » Fri Dec 09, 2005 2:26 pm

I am not sure where the jury sits on this one ... but I thought it was recommended NOT to break a motor in with a synthetic ??

81spitfire · Post by **81spitfire** » Fri Dec 09, 2005 2:32 pm

ive heard both ways on that one and i think the conclusion ive come to is its ok but you have to give it a longer break in time.

grasscutter97 · Post by **grasscutter97** » Fri Dec 09, 2005 11:30 pm

The synthetic thing always opens up a can of worms. I do know that most new sleds are coming from teh factory with synthetic. I've personally done ALL of my rebuilds with 100% synthetic from the first mile. With the oil injected sleds, add a little mix to the gas AND keep the oil tank full. I'm just now breaking in a top to bottom rebuild on a JD300 (new crank on up), and am using 100% synthetic @ 50/1. Just about 100 miles on it now, and compression is right on and looking in exhaust ports, its till shiny and clean! That's my story anyways!

ProJd69 · Post by **ProJd69** » Sat Dec 10, 2005 5:10 am

Like the manuals says (well for the 80's). MIXTURE 40:1 for the first tank and then 50:1. Do NOT exceed 40 mph (64km/h) for the first 25 miles (16 km), or force the machine at full throttle in deep snow. An occasional burst of power on hard-packed snow will not be harmful.

I would say if you have replaced eveything- pistons, rings ext, ext. ALL but the case, jugs and heads. Then it would be just like new.

For the synthetic Oil- if you have the $, Its not to much more but its WELL worth it for the added protection. Its just a flat out better OIL to use.

Mailman · Post by **Mailman** » Sat Dec 10, 2005 9:49 am

Would it make any difference or harmfull to switch from standard to synthetic on a motor that has been used for several years since O/H?

:unsure:

grasscutter97 · Post by **grasscutter97** » Sat Dec 10, 2005 4:48 pm

You can switch over to synthetic at ANY time, in ANY vehicle (sled, car, truck, whatever) with zero problems. Most folks don't realize that the vast majority of car manufacturers are putting synthetics in from the factory. The first few miles the new owner drives are the most vital for engine protection and ONLY synthetic gives that protection. Check out a race pit crew, whether its NAscar or race sled, every racer is using synthetic. And don't get fooled when a team advertises for plain old Quaker State. That is simply advertising dollars at work. It means nothing as to what they are actually using in their vehicles.

A friend of mine used to work in the body shop of a pro-nascar race team. Since this crew had an ad deal with a major oil company, they had to have the oil bottles displayed in the pit area. The funny thing was...the oil company didn't care if they re-filled their brand 'x' quarts with whatever race synthetic the crew lead mechanic wanted. Kind of funny!

wadeo108 · Post by **wadeo108** » Sun Dec 11, 2005 12:43 am

break it in like you plan on ridding it. if you will ride it like you stole it then break it in that way.
it is a load of crap when they tell you to take it easy. if you follow there rules with the snow we have been having lately it will take 3 years before you can open it up.
when i bought my cat i picked it up got it home and put 2 miles on it grass dragging it against my brothers zr. 0 miles and wide open. i've never had a problem with it.

Post by **ICCSF 108** » Sun Dec 11, 2005 2:52 am

I agree with the guy above, SOMEONE must have taught him well, If it works for him why not, hey balls to the wall boys

Hey how come I never get entered in the deere of the month?

De Old Man

Rodimus Prime · Post by **Rodimus Prime** » Sun Dec 11, 2005 8:07 am

mostly breaking in an engine is a matter or personal preference since what matters most is how well the engine was put together.

engine breakin is plainly seating the rings to piston.

brand new pistons and rings that are tight in bore should be driven slowly never exceeding 3/4 throttle for first tank of fuel and NEVER hold the throttle in one position to long.

if you go wide open throttle right away on a tight engine it WILL sieze.

engines that have some piston slap or just new rings on old pistons while adviseable to vary throttle often and not go wide open throttle you can without major damage..however the rings will not last long...there will actually be grooves in piston ring area and the rings..

full synthetic oils DO NOT MIX with non synthetic oils. most synthetics now are blends that can be used in regular oils.

for those who dont know factory engines are pre broken in.. engines are turned externally for a set period of time to seat rings.

the above is not a general rule but is common for atv manufacturers. other 2 cycle (chainsaws, weed eaters etc. are NOT broken in and make a hell of a mess )

disfunctionals · Post by **disfunctionals** » Tue Dec 13, 2005 2:06 pm

i stand in the middle. i dont believe in the complete break in process but i dont believe in balls to the walls immediatly either. i would ride it a lot harder than the factory would recomend, but i wouldnt open it wide open for the first tank. and mixing richer is a good and safe idea.

Deleted User · Post by **Deleted User** » Sun Dec 18, 2005 4:21 pm

Thanks for all the help guys, I took it easy for about a tank then rode it a little harder. It's running awesome, thanks for all the help

-Abe