Breaking in new rings
- Thread starter Jbevs
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Sounds to me as if you answered your own question.My last one I put a new piston and ring in a 350 Husqvarna. Enriched the carb up a bit and went and cut wood.To tanks later readjusted the carb and all is well.Ken
I sure tried to. That is what I have gathered from the search function, but it was only in reference to brand new saws. Asking the question directly gets me a direct answer.
Fuel it up and run it as normal. Taking it easy at first is for a new piston. Put a load on those rings from the get go.
You need it under load for the rings to seat, but sustaining that load is not a good thing.
I use the first tank cutting limbs...it puts the saw under load, but keeps the rpm varied.
I go easy on oiling the piston too...too much is not a good thing.
I use the first tank cutting limbs...it puts the saw under load, but keeps the rpm varied.
I go easy on oiling the piston too...too much is not a good thing.
Some intertesting stuff here:Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power.
zogger
Tree Freak
Nice article
thanks for the link. I've only had a few "new" engines in my life (ones I rebuilt myself) and that fast oil change is what I always did, for the same exact reason, like ten to 20 minutes running the engine, then change the oil. Start it up,. warm it, around the block, down the road, hit some stop signs and jack rabbit away from them, out on the highway for one exit, back home, oil change time, like that. I never did like five hundred miles or anything like that, more like ten miles or something. I used cheap oil for the initial run, then switched to what I was going to use. Seemed to work OK that way. I just never trusted all those little particles slopping around on the new parts....just seemed wrong to me to push it for hundreds of miles.
Saws..I am two for three on new engines, two made it a long time, one toasted, but I know that one was running too lean and I didn't know much better at the time, now I do.
Hmm, two strokes...just wondering, seeing as how there is no oil change per se....run it hard at first with a richened mixture (like guys here sometimes say, run it like you stole it), then tear it down again and rinse it all out/clean it thoroughly, then reassemble again. Wash out the crankcase and piston and cylinder, etc with something. Get those particles out of there, the first "wear in" particles. Use dino oil for the mix at first, then after cleaning switch to syn or syn blend. Don't know, just thinking about it..coupla tanks, then the wash...
thanks for the link. I've only had a few "new" engines in my life (ones I rebuilt myself) and that fast oil change is what I always did, for the same exact reason, like ten to 20 minutes running the engine, then change the oil. Start it up,. warm it, around the block, down the road, hit some stop signs and jack rabbit away from them, out on the highway for one exit, back home, oil change time, like that. I never did like five hundred miles or anything like that, more like ten miles or something. I used cheap oil for the initial run, then switched to what I was going to use. Seemed to work OK that way. I just never trusted all those little particles slopping around on the new parts....just seemed wrong to me to push it for hundreds of miles.
Saws..I am two for three on new engines, two made it a long time, one toasted, but I know that one was running too lean and I didn't know much better at the time, now I do.
Hmm, two strokes...just wondering, seeing as how there is no oil change per se....run it hard at first with a richened mixture (like guys here sometimes say, run it like you stole it), then tear it down again and rinse it all out/clean it thoroughly, then reassemble again. Wash out the crankcase and piston and cylinder, etc with something. Get those particles out of there, the first "wear in" particles. Use dino oil for the mix at first, then after cleaning switch to syn or syn blend. Don't know, just thinking about it..coupla tanks, then the wash...
I think disassembling the motor kind of defeats the purpose of letting the rings seat in the first place. I could be wrong though.
kugss
ArboristSite Operative
My shop teacher always said "when breaking in a new motor take a BIG girl on a date up a BIG hill"
rms61moparman
Addicted to ArboristSite
Break it in just EXACTLY like you are going to run it.
Why teach an engine to run easy then have to re-teach it again to cut wood?
Mike
Why teach an engine to run easy then have to re-teach it again to cut wood?
Mike
zogger
Tree Freak
I was thinking just pull the cylinder off after running maybe a couple tanks. spray it all down with something to clean it, rinse it out with some mix fuel, drain it, blast it out with the compressor, final little few dabs of mix oil on the bearings sides, and do the same to the piston while it is still attached to the rod. Clean and wipe down and reassemble cylinder back on. No need to take it down past that point. Ring or rings will wind up in the same exact spot, so that's a wash.
Never done it, but theoretically, you *are* breaking it in and accumulating a lot of fine particles in there.
Saws obviously can last a long time without doing that..imagine if you DID clean them out after a breakin period and before long term use.
I typed a longer response last night, but when I hit "submit", I got back a message saying the server was busy.
The rings need to be worn in under load, because you need the pressure behind the rings to push them against the wall.
It is important to remember, however (in response to moparman's question), that in addition to improving the seal, the wearing-in also increases the surface area where the ring contacts the cylinder wall. This is a critical point of heat transfer for the piston.
If you run it at a heavy load, for an extended period, the fact that the rings aren't bedded means that they will get too hot. If this happens, the heat can oxidize the oil between the ring and cylinder. This oxidized oil is called "glaze", and once glaze forms, wearing-in stops. That is why you should vary the load initially. It keeps the pressure up, and the temperature down.
That is why I use the saw for limbing for the first tank.
Because of the differences in lubrication, the particles that form from wearing-in are not likely to collect in the crankcase. My guess is that they already have gone where they are going, and are too fine to cause any real concern.
Its funny you say that Mike! At the GTG, was the first my 5200 had seen wood, since I put new rings & seals in it. I put it in 30+" oak log, and let it all hang out. Ran it several times that day. Seems real strong. Thats the size wood it was cutting before, and will be cutting in the future.:msp_biggrin:
Gregg,
rms61moparman
Addicted to ArboristSite
Its funny you say that Mike! At the GTG, was the first my 5200 had seen wood, since I put new rings & seals in it. I put it in 30+" oak log, and let it all hang out. Ran it several times that day. Seems real strong. Thats the size wood it was cutting before, and will be cutting in the future.:msp_biggrin:
Gregg,
My whole point is that normal use gives all the necessary elements to creating a good ring seal.
Short of strapping a saw to a mill and milling a few 16' red oak logs I can't see any way that you will do anything but benefit from breaking it in like you are gonna use it.
Indeed (IMHO) to cut limbs with a saw and get it broken in to the stresses that presents and then drop it into Greggs 30" log is in essence breaking it in twice and will do more harm than good.
Do what you want but that is my method and until I have a failure, I'm sticking to it.
Mike
That's what I'm trying to explain, if you get glazing, the bedding process stops prematurely. You won't get as good of a ring seal.
Breaking in isn't about getting the engine used to stress...it is about bedding the rings. If it is more than just the rings being replaced, however, I do heat cycle the engine.
It isn't a matter of failure, just how well the rings get seated. The better bedded in the rings are, the better the seal, and the more heat the piston can shed. More heat out of the piston is more fuel in the cylinder.
In all likelihood, the differences will be negligible...but understanding the process makes for better decision making.
