Break in time for rings to seat

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clutch25

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I have seen MANY threads on many boards about this topic...I didn't do a search on here but I'm sure this has been covered before but with new blood always coming on board (me included), perhaps we could cover it again.

I have rebuilt sleds, bikes, quads and all sorts of stuff...

I see alot of people on here saying, "run X tanks of gas through it and it will seat the rings". On the sawing I have done (not much, shamefully), a couple of tanks of gas will last quite a while in my 361.

Some of my experience with rings seating in a new cylinder are as follows:

Quad (Honda TRX 450R, NiSil cylinder, nitride rings, liquid cooled) literally like less than 5 minutes run time at slightly lower rpm than saws (6-10K range). 4 stroke.

Sled (Arctic Cat ZR 600, Suzuki twin cylinder, NiSil cylinder, ducticle rings?, liquid cooled) around 10 minutes tops.

I have done MANY ATV engines with both cast iron bores and NiSil and it has rarely been longer than 10 minutes.

Any thoughts?
 
Alright here it goes just run some good mix in it 50:1 is fine make sure the saw isnt running lean a little rich in the beginning is probably better because as the rings seat the saw will start to lean out a little dont hold it revved up out of the wood and just run it like you stole it.
 
Just realized I didnt really answer the question it will probably take about 6-12 tanks of gas before they are completely seated.
 
Does anyone ascribe to the less common theory of letting the engine get good and warm and then running it like a raped ape first time out?

I sure don't have any real-world experience to back it up but the way it was explained to me makes since.

You don't want engine to run very long with "slop" in the rings so go ahead and get the rings "smashed" from the get-go so you'll have a seal that was influenced as little as possible by the wiggle room.

You know right off the bat if everything is working right. That may be a plus or minus...I know I'd rather find out something was wrong from the start instead of "planning" on it being good and finding out a week, or a month later I forget to pay attention to a bearing or something.

Not a mechanic, not by a long shot, but curious to see if anyone else has heard of this.

I know that for engines and gun barrels, I've never given "break-in" much attention...and to my knowledge I can't think of a single time it's come back to haunt me.

I don't even soak my new chains, just run a bead of pen. oil down the top of the bar and make sure I run the saw out of wood long enough to let the oiler spread it's goo around.
 
I'm not sure there is a definitive answer...


Diesel motors (Our bobcat S205 Turbo took like 20 hours) and gas motors, all of them take longer.

Just run the damn things, not too hard, not too rough... but run them in/
 
Well, what does "setting mean?

Well, what does "setting mean? I would take it to me would be less blowby the rings and increased compression.

Do you have a freshly built saw? If you do, take a compression reading right off the bat and then every so often and see what the compression does.

edit....so, no one considered my thought? Or am I on ignore?

Dan
 
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You got lots of variables to deal with before anybody can really answer this. Each situation is different. Is the bore cast iron, chrome, or silicon aluminum?
Which ring set is used cast, moly, nitride, etc. How does the manufacturer want the bore to be honed for a particular ring set. Most modern engines are using hardend bores and ring sets with very low tension. They need perfect bores to seal which they will... instantly. The old style cast iron ring will conform to a bad bore to some extent. On these be kind. Rich mixes and plenty of oil. Vary the RPM's. The amount of time required is dependent on how bad the bore is. No two are the same. If you need more info there's plenty out there. Just depends on how bad a headache you want.:cheers:
 
I've always treated my bike rebuilds and saw rebuilds alike.

Do a couple of short warm up/cool down cycles at the very beginning and more than anything, just make sure it's not running lean.

Then just use them normally, but don't abuse them at WOT for extended periods of time.

Every engine failure I've ever had let go within the first 5 minutes of running. If it survives the first 5 minutes, it'll survive just about any break in method as long as it's not running lean.
 
Break-In

Clutch25--

Get yourself a STIHL Owners/Operators Manual.
Most dealers have plenty of extra copies.

It details Breaking-In instuctions pretty well.
It is NOT to "run it like you sole it" from minute one.

At least it's what a large manufacturor thinks & states!
 
I've always just started the dang thing and went and cut the crap out of stuff... brand new saws right off the shelf... never gave it any thought...

Never had a breakdown or a "break in" related problem


...just go cut wood!

Gary
 
Same here Gary,ever saw I ever bought just went straight to cutting,and never thought anything about it.
 
I've always just started the dang thing and went and cut the crap out of stuff... brand new saws right off the shelf... never gave it any thought...

Never had a breakdown or a "break in" related problem


...just go cut wood!

Gary

Yep! :greenchainsaw:
 
Thanks guys!

BTW...I have the owners manuals for everything....just wanted to start a discusion about break in time.

Most of the two stroke failures I have see are from piston skirt wear (many hours), lean burndown and ALOT of cold scoring either from snow/water ingestion (snowmobiles) or no warm up time.

I agree with the comments about failures in the first 5 minutes and Gary's comment.... I make sure it is up to temp (maybe heat cycle once or twice) and then go run the snot out of it.
 
Owner's Manuals ?

It's interesting how we love a Manufactuors product, STIHL, Husky,
Dolmar, et al. , but care not a whit for their instuctions.

It would be very interesting to have a STIHL engineer reply to this thread.
Early heat cycles, per STIHL, are very important for the engine AND chain.

Hey, but what do they know??
They just designed & made the stupid thing!

If running the snot out of it from minute one is OK for some A/S members,
surely that supercedes all that STIHL could say.
 
It's interesting how we love a Manufactuors product, STIHL, Husky,
Dolmar, et al. , but care not a whit for their instuctions.

It would be very interesting to have a STIHL engineer reply to this thread.
Early heat cycles, per STIHL, are very important for the engine AND chain.

Hey, but what do they know??
They just designed & made the stupid thing!

If running the snot out of it from minute one is OK for some A/S members,
surely that supercedes all that STIHL could say.


Thats what some people call experience!

:popcorn:

7
 
FWIW I used to have to run in lots of air cooled kart engines over twenty years ago, (geez, am I that old now :jawdrop:) mainly reed and rotary valve screamers and I had to build the heat cycles up slowly over 45 minutes total run time. If I didn't I'd get a size 10 up the arse from the engine builder, who watched like a hawk.
Used Castrol R30 at 16:1, premium unleaded.

Started off for 5min, little throttle and lots of choke (hand over carby) to keep the piston cool, then stop and let cool down.
Restart and similar but longer run cycles up and down the rev range, extending further and further until you ran them at full snot. (at the time, 18-19,000RPM or so)

If you didn't follow this religiously the bloody pistons would seize big time.
 
It's interesting how we love a Manufactuors product, STIHL, Husky,
Dolmar, et al. , but care not a whit for their instuctions.

It would be very interesting to have a STIHL engineer reply to this thread.
Early heat cycles, per STIHL, are very important for the engine AND chain.

Hey, but what do they know??
They just designed & made the stupid thing!

If running the snot out of it from minute one is OK for some A/S members,
surely that supercedes all that STIHL could say.


Maybe they have changed the wording in the manuals recently, but mine says, basically, don't run wide open throttle with no load for the first three tanks. I would suspect that "run the snot out of them" means just that...buried in wood. That's how I do it also.
 

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