Break in time for new pistons and rings ?

mwood1129

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I am putting new pistons and rings in my Z750a Kubota engine. What would you guys recommend for a break in period? I am a gas engine guy. Not very familiar with small Diesel engines
Thanks in advance
 

85Hokie

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I would run it somewhat easy for about the first 50 hours.... oil/filter change after and move forward.
Vary the rpms a bit , but dont baby it .......... diesels need to be run at their torque heavy rpm, so - I would run it 50-75% rpms for a bit depending on what you are doing.
 
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lugbolt

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I would run it somewhat easy for about the first 50 hours.... oil/filter change after and move forward.
Vary the rpms a bit , but dont baby it .......... diesels need to be run at their torque heavy rpm, so - I would run it 50-75% rpms for a bit depending on what you are doing.
if the machine work was done right, cylinders untapered and round with the correct grit hone, they'll be seated in 10 minutes or less.
 
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skeets

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I was told run it like you stole it
 
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mwood1129

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Kubota l175
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if the machine work was done right, cylinders untapered and round with the correct grit hone, they'll be seated in 10 minutes or less.
Thanks for the information.
All I do with this tractor is pull a finish mower cutting about 10 acres. So grass is tender and green . The throttle setting of 50%-75% should do fine .
 

mcfarmall

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Run it like the farmers and excavation contractors run their brand new equipment.
 

GreensvilleJay

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re:

All I do with this tractor is pull a finish mower cutting about 10 acres. So grass is tender and green . The throttle setting of 50%-75% should do fine .

I was told to VARY the engine speed, not 'set and forget' for the first few hours/miles of 'break in' period. So run a little fast, then slow,maybe fast then mid range, ..mix it up, every so often. I did that 700+ hrs ago with my BX23S, zero problems.
 

Tx Jim

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I had new pistons/liners installed in my 120 HP tractor last yr. I recommend utilizing break-in oil until 1st oil change. I just put my tractor to work doing the task it's performed for yrs IE pulling rd baler making 4X5.5 rd bales. I suppose the rings seated fine because it uses no oil between oil changes
 
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lynnmor

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I had new pistons/liners installed in my 120 HP tractor last yr. I recommend utilizing break-in oil until 1st oil change. I just put my tractor to work doing the task it's performed for yrs IE pulling rd baler making 4X5.5 rd bales. I suppose the rings seated fine because it uses no oil between oil changes
Piston rings need some speed to quickly seat properly, other engine parts may be damaged if the fit isn't ideal with excessive speed. When saying that you used break-in oil, I guess that it was an oil with high ZDDP content, which will add some protection. It is all a balancing act and the fans of running a new engine hard are not dealing with reality. I think that you will find that new tractors have been started and stopped repeatedly as the dealer moves them in and out of the shop for assembly and fitting of attachments, that golden hour of treating a new engine properly is totally lost in the shuffle.
 
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Dieseldonato

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You need load to break in rings, not static, dynamic load. Ie put it to work. Load the rings. The pussy footing around is for cam shaft break in. If it's the original cam there's really no need to light load it or vary the engine speed the rings don't care. If the machine shop has done their part right and the guy assembling it did his job it will work.
I've dynoed plenty of engines and will tell you from first hand experience the rings seat up a lot faster then you think. Normally minutes. Letting it get up to temp is arguably more important then the speed of the engine, then go to work.
Deere was/is a big fan of their break in oil, I've never seen a major difference in the engines that were ran with it or not.
 
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dlsmith

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When I had the C15 CAT engines in my trucks overhauled, I asked how to break them in. The CAT shop manager said to drive them just like normal, don't baby them and MOST important, watch for any leaks.
 
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