550XP mark 2 / 572 fuel mixture with pipe

[Tomos770]

New design seems to have bigger openings on inner side (for better lubrication)

https://www.wolfswinkel.shop/husqvarna-parts-parts/525434205/husqvarna-group-ball-bearing

 

[Tomos770]

SKF BB1-3023-AD

https://www.skf.com/ph/productinfo/productid-BB1-3023 AD

 

[retiredfarmer]

I have just used husqvarna s canned gas

 

[Husky77]

50-1 good oil and dont try and cut with a dull chain. More saws are ruined through forcing a dull chain to cut than running at 50-1

 

[Bowhonk]

Greetings,

Picked up these two saws over winter, great overall saws. 550 has 18" bar and 572 has 24". I have run about 5-6 tanks of fuel through the 550 and only about 1 through the 572. I have been using 50:1 ratio as the dealer suggested. Echo power blend oil. 89 octane fuel unfortunately with ethanol as non-ethanol is not available unless I buy the canned fuel from the dealer. I just added a pipe to the 550 and have one on order for the 572 from chainsawperformanceparts.

What I have been reading lately and would like to verify that some people suggest running a richer mixture on these saws of 40:1 or even 32:1 because of the speed they run at and to extend the life of the saw. What are the overall thoughts on this fuel mixture change or changing the mixture after adding a pipe to the saw. I also added a single air vent to the air cleaner cover on the 550 and am considering doing the same on the 572. Should I change any of the above oil, fuel or mixture that I have been using?

I have also read that the pipe keeps the saw running cooler? Possibly extending the life of the saw? These two saws are just for use around the farm and for fun. I would like them to last a very long time.

Thanks for any suggestions.
Sean

My 1st suggestion is Run the pre mix husky gas. I was totally against it till I tried it. Quite a noticeable difference and the amount the Lil 550 burns its Werth it. The pipes will definitely make it run cooler and live longer. My old saw has 12 years hard werk on it, original top end still looks new only been mixxed to 50:1. I mix them rich when the bugs are bad. Lol. Don't add the vent to air box...the cooling fan blows thru them to keep the filter from plugging with sawdust. And snow dust out in winter to keep from freezing up. They're auto tune, so that's retard proof can't blowem up no more tuning them wrong.
Another point on the pre mix gas....I have a sthil 271 30cc I bought for the wife...ran like poo didn't matter what I did to it from new. For ***** n giggles I ran a tank of the husky pre mix in it as last resort before smashing it. Lil basterd runs like a top, still not sure why, even the pre mix sthil gas wouldn't run good in it. Cover for 3yrs factory warranty also buy 3 cans when u buy the saw new.
My thoughts enywheyysss. Happy cutting

 

[pioneerguy600]

SKF BB1-3023-AD

https://www.skf.com/ph/productinfo/productid-BB1-3023 AD

I have yet to see where a bearing did not like extra oil, on the other hand lack of oil like in dry,no oil conditions they did not like that.

 

[Husky77]

The 5 series are a modern saw which husqvarna recommend a 50/1 mix "with their oil" no doubt it is a good oil and no doubt this will raise a few eyebrows. I'm talking Europe here and cant see why someone would want to run a modern saw on a 32/1 mix, I dont know anyone that does or would these days, your talking back in the 1960's when it was 16/1 & 32/1 was considered risky.
If you dont want to follow husqvarna Adobe and run 50/1 at least try 40-45/1. I been running 50/1 since the 1980's and never blown a saw up, I have a 550 that's a great little saw I love it and spoil her with 45/1 motul 800 inspect inside regular and always clean and nicely oiled, cant ask for more.

 

[old guy]

I run 40:1 in all my saws, old & new.

 

[huskihl]

The 5 series are a modern saw which husqvarna recommend a 50/1 mix "with their oil" no doubt it is a good oil and no doubt this will raise a few eyebrows. I'm talking Europe here and cant see why someone would want to run a modern saw on a 32/1 mix, I dont know anyone that does or would these days, your talking back in the 1960's when it was 16/1 & 32/1 was considered risky.
If you dont want to follow husqvarna Adobe and run 50/1 at least try 40-45/1. I been running 50/1 since the 1980's and never blown a saw up, I have a 550 that's a great little saw I love it and spoil her with 45/1 motul 800 inspect inside regular and always clean and nicely oiled, cant ask for more.

Motul 800 with its high viscosity at 45:1 is very similar to running husky oil at 32:1…

I believe the strato thing was mentioned earlier in this thread or at least it’s in several others. The bearings in a 5 series see about 25% less oil than a conventional saw. 50:1 with run-of-the-mill oil works fine for most homeowners who only put 10 hours of actual run time per year on a given saw. 20 years = 200 hours. Everyone is happy.

But the arborist whose 4 month old 550 with 200 hours that just **** out it’s case bearings isn’t going to be real happy

 

[bwalker]

Motul 800 with its high viscosity at 45:1 is very similar to running husky oil at 32:1…

I believe the strato thing was mentioned earlier in this thread or at least it’s in several others. The bearings in a 5 series see about 25% less oil than a conventional saw. 50:1 with run-of-the-mill oil works fine for most homeowners who only put 10 hours of actual run time per year on a given saw. 20 years = 200 hours. Everyone is happy.

But the arborist whose 4 month old 550 with 200 hours that just **** out it’s case bearings isn’t going to be real happy

I agree completely with Kevin's assessment. Strato saws run hotter and are less lubricated than traditional two strokes.
I just bought a 550xp and it will be muffler modded immediately and ran at 32:1.

 

[Ridgehiker]

what makes them recieve less oil?

 

[bwalker]

what makes them recieve less oil?

As fuel consumption goes down cooling decreases and lubrication decreases. This is because when fuel/oil mix enters the motor in liquid droplet form it mostly flashes into a vapor which absorbs heat and deposits oil on the rotating assembly.
Now some guys will falsely claim that better fuel economy just means that less fuel and oil is blown put the exhaust. This is false because that fuel in the exhaust is in a vapor and thus the oil has been deposited in the motor and the cooling effects of changing phase have already happened.

 

[Lionsfan]

I agree completely with Kevin's assessment. Strato saws run hotter and are less lubricated than traditional two strokes.
I just bought a 550xp and it will be muffler modded immediately and ran at 32:1.

Ran mine just like that the first couple seasons. When I had it ported he said it was certainly getting plenty of oil, and 40:1 would be plenty in the future.

 

[bwalker]

Ran mine just like that the first couple seasons. When I had it ported he said it was certainly getting plenty of oil, and 40:1 would be plenty in the future.

Where you running red armor?

 

[Lionsfan]

Where you running red armor?

Dominator. Running Red Armor now, sounds like the end results are similar with those 2.

 

[Tomos770]

I agree completely with Kevin's assessment. Strato saws run hotter and are less lubricated than traditional two strokes.
I just bought a 550xp and it will be muffler modded immediately and ran at 32:1.

What do you think....is it wise to re-bore its main jet by 10%...

 

[bwalker]

What do you think....is it wise to re-bore its main jet by 10%...

Autotune will tune accordingly just fine ime.

 

[Tomos770]

We are talking about mk2 here right?

Pay attention on the details in/at its exhaust port.....you have one intentional lip on the upper side of port....EPA?

And when piston is @TDC....its positioned approx 1mm to high...maybe its edge could be polished for a better flow?

 

[huskihl]

What do you think....is it wise to re-bore its main jet by 10%...

It’s not that they run lean on fuel, or at least they don’t run hot even though there is less fuel cooling the piston skirt. The main detriment to them is the lack of oil going through the bottom end of the motor. If you were to drill the main, the autotune would just correct itself back out because it still needs14 parts of air to 1 part fuel to make the most power.

The MS 261c is the only one so far where the early versions would not put out enough fuel in certain circumstances. Drilling the version 1 and version 2 Mtronic jets to the same as version 3 fixes that

 

[huskihl]

We are talking about mk2 here right?

Pay attention on the details in/at its exhaust port.....you have one intentional lip on the upper side of port....EPA?

And when piston is @TDC....its positioned approx 1mm to high...maybe its edge could be polished for a better flow?

View attachment 1203699View attachment 1203700

Nearly every exhaust port versus piston height is like that. The port needs volume for performance and that’s how they get the port bigger without affecting the plating.