best way to break in a newly rebuilt saw

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NZ dave

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Got a Husky 365 special that's got a dead cylinder and piston (deep scratch in cylinder).

I've purchased a meteor piston and cylinder plus piston bearing and caskets so i can get the saw up and running again.

Question is what ratio to use?

Looked at these postings and i have usually used 40:1 using 91 octane (Note I'm in chch NZ) the saw was hard to start with when i brought it 2nd hand and was only late last year that it wouldn't start and keep running at all....
https://www.arboristsite.com/community/threads/best-way-to-break-in-a-never-been-started-saw.211498/

Also should i put some mix into the base of the saw so the lower bearings get a splash of oil n gas before putting cylinder on.

Oh and other thoughts plz

Look forward to you're thoughts.
 
Use the same ratio you will run after the saws broken in.
I run my saws a touch rich on the high for a couple tanks before tuning them to rev like they should. ie set it to max out at 12500 instead of 13500.
I don't bother putting premix in the base as the saws I've worked on still had a oil film on the bearings from when they ran last but it wouldn't hurt anything.
 
I think it’s a good idea to try to get a wee bit of oil on the mains. You should flush the cases with premix by pumping the crank and draining a time or three. That should suffice for lube, especially if you’re at 20:1 or so for this flushing step.

It’s imperative to lightly oil the piston ring/groove and the wrist-pin bearing. Use straight mix oil.

I also apply (with a clean finger) a very light coat of oil on the cylinder wall. Some like the cylinder dry with either no oil or a tiny wisp of oil in the ring groove..

Assemble and run a partial tank. Then re-torque all the disturbed fasteners to make sure everything is still tight.

Since the bottom end is already broke in being a used saw, run it like you stole it in a limbing application for 10 minutes or so and then bury it for a few cuts (tuned a little rich as mentioned) Break-in complete. Check your bolts, retune and enjoy!

Oh, and run 40:1 or so..:chainsaw:

Some may disagree on all of this. Lol.
 
Got a Husky 365 special that's got a dead cylinder and piston (deep scratch in cylinder).

I've purchased a meteor piston and cylinder plus piston bearing and caskets so i can get the saw up and running again.

Question is what ratio to use?

Looked at these postings and i have usually used 40:1 using 91 octane (Note I'm in chch NZ) the saw was hard to start with when i brought it 2nd hand and was only late last year that it wouldn't start and keep running at all....
https://www.arboristsite.com/community/threads/best-way-to-break-in-a-never-been-started-saw.211498/

Also should i put some mix into the base of the saw so the lower bearings get a splash of oil n gas before putting cylinder on.

Oh and other thoughts plz

Look forward to you're thoughts.
You can put straight 2 stroke oil on wrist pin bearing, rod bearing, case bearing and coat cylinder before assembly. I always do, it smokes a little more at start up, but clears right up. Run it a little fat for a tank and then run it. Everyone has a plan.
 
You can put straight 2 stroke oil on wrist pin bearing, rod bearing, case bearing and coat cylinder before assembly. I always do, it smokes a little more at start up, but clears right up. Run it a little fat for a tank and then run it. Everyone has a plan.

Exactly what I do [emoji1303]
 
All three of my saws I used 40:1 good mix and ran the piss out of em till the tank was empty. Pretty much cutting cookies for two tanks. It’s been almost a year and pistons look great through the exhaust port.
This issue has been covered so many times here by searching, everyone has their own way of doing it. In the end, modern oil mixed with non ethanol gas, a good condition saw with no air leaks, and a sharp chain, there’s no wrong way to breaking it in than that.
 
I’ve heard that after the initial start up...let your saw idle for about 30 minutes...(rich mixture) then go from there...it ought to gain compression after 2 tankfuls of mix...Happy sawing..!!
 
Having a chrome cylinder and chrome rings it takes a lot of time to fully break in.

First when i assemble any two stroke before I put the cylinder on I give the crankcase wall above both crankbearings a shot of two stroke oil to pre lube them. I tilt the saw so the oil runs down into the bearing. I burnish a moly paste or anti seeze into the cylinder walls and piston skirt I pre lube the rod ends, piston skirt and cylinder with oil and assemble. I run my mix a tad oil rich anyway I’m under 40:1. I start it up let it idle so the crankcase gets fogged with oil. Then let it warm up, adjust the carb low speed and idle then rev it up to adjust the high speed.

TS-70 moly, www.tsmoly.com

Moly is that grey engine assembly lube it comes with cam shaft kits too. It eliminates all wear, reduces friction, prevents galling, fights corrosion and doesn’t attract dirt.
I use moly in lubing everything. I use moly grease too.
 
Been a while and have been unable to get back on till now,
Thanks for all the comments, They all sorta repeat what was said on the other forum URL i put up so thanks all n hope this posting helps others in future with regards to
fitting a new cylinder/piston to a saw.
 
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