40:1 fuel mix in a 50:1 engine
- Thread starter Alfred_B
- Start date
It won't make a difference either way. Those who run 32:1 or 40:1 because it makes them feel better are usually also the ones who change their synthetic oil every 3,000 miles. If 50:1 wasn't good enough the manufacturers would have piles of warranty claims. Oil technology now is way ahead of what it was even 5-10 years ago. Heck I know landscapers who run their 2 stroke machines at 100:1 or 80:1 using Opti-2 or Amsoil Saber with zero issues for hundreds of hours. They always manage to destroy the machine in some other way before the engine has any issues.
Do it if it makes you feel better, but a noticeable difference in longevity compared to what is recommended by the manual is not likely.
Do it if it makes you feel better, but a noticeable difference in longevity compared to what is recommended by the manual is not likely.
Originally Posted by jeepman3071
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
Originally Posted by Astro_Guy
Originally Posted by jeepman3071
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
My Craftsman blower has 40:1 on the fuel cap, as you mentioned. I've been running 50:1 in it (Husqvarna semi-synthetic mix, or Briggs 2 cycle oil) since it was purchased in 2006. I took the muffler off last year to check carbon build up and the piston + rings looked great, and compression was perfect. My guess is that it has around 60 hours of use on it.
Originally Posted by jeepman3071
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
My Craftsman blower has 40:1 on the fuel cap, as you mentioned. I've been running 50:1 in it (Husqvarna semi-synthetic mix, or Briggs 2 cycle oil) since it was purchased in 2006. I took the muffler off last year to check carbon build up and the piston + rings looked great, and compression was perfect. My guess is that it has around 60 hours of use on it.
Originally Posted by Alfred_B
Yes, my Lawn Boy calls for 32:1 and smokes like crazy.
I have a 6.5HP LawnBoy and mix Castrol TTS or the old Mobil 1 MX2t at 32 to 1. It only smokes a little upon startup and then operates smoke free. Which model do you have?
Yes, my Lawn Boy calls for 32:1 and smokes like crazy.
I have a 6.5HP LawnBoy and mix Castrol TTS or the old Mobil 1 MX2t at 32 to 1. It only smokes a little upon startup and then operates smoke free. Which model do you have?
Originally Posted by jeepman3071
Originally Posted by Astro_Guy
Originally Posted by jeepman3071
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
My Craftsman blower has 40:1 on the fuel cap, as you mentioned. I've been running 50:1 in it (Husqvarna semi-synthetic mix, or Briggs 2 cycle oil) since it was purchased in 2006. I took the muffler off last year to check carbon build up and the piston + rings looked great, and compression was perfect. My guess is that it has around 60 hours of use on it.
I also want to mention that I'm not recommending to ignore the owner's manual. I simply run 50:1 in all of my 2 stroke equipment, and this blower is the only thing I own that recommended 40:1. I realized this about 6 years after owning it/running it on 50:1.
Originally Posted by Astro_Guy
Originally Posted by jeepman3071
If 50:1 wasn't good enough the manufacturers would have piles of warranty claims.
Okay - but all the new Craftsman brand stuff I've seen calls for a 40:1 mix. Perhaps this simply reinforces your argument?
My Craftsman blower has 40:1 on the fuel cap, as you mentioned. I've been running 50:1 in it (Husqvarna semi-synthetic mix, or Briggs 2 cycle oil) since it was purchased in 2006. I took the muffler off last year to check carbon build up and the piston + rings looked great, and compression was perfect. My guess is that it has around 60 hours of use on it.
I also want to mention that I'm not recommending to ignore the owner's manual. I simply run 50:1 in all of my 2 stroke equipment, and this blower is the only thing I own that recommended 40:1. I realized this about 6 years after owning it/running it on 50:1.
This is a very interesting thread.... youre making me reconsider my strict -1 gas can for each blend- required... 50:1 - 40:1 and 32:1
so would it be a realistic to shoot in the middle with a 40:1 and run all 3 types of OPEs on the same blend..??
Originally Posted by 2K2AcuraTL
This is a very interesting thread.... youre making me reconsider my strict -1 gas can for each blend- required... 50:1 - 40:1 and 32:1
so would it be a realistic to shoot in the middle with a 40:1 and run all 3 types of OPEs on the same blend..??
Absolutely - run them all at 32:1 or 40:1
The caveot is that the carbs MUST be adjusted to run with the new ratio, otherwise you are leaving something at the table.
This is a very interesting thread.... youre making me reconsider my strict -1 gas can for each blend- required... 50:1 - 40:1 and 32:1
so would it be a realistic to shoot in the middle with a 40:1 and run all 3 types of OPEs on the same blend..??
Absolutely - run them all at 32:1 or 40:1
The caveot is that the carbs MUST be adjusted to run with the new ratio, otherwise you are leaving something at the table.
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carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
Originally Posted by super20dan
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
That's true. Many emissions compliant engines are non adjustable. However, there are a few two stroke engine carbs where the adjustment is simply hidden inside the throttle plate itself. The owner would never see it unless he knew to pry off the cover and adjust it.
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
That's true. Many emissions compliant engines are non adjustable. However, there are a few two stroke engine carbs where the adjustment is simply hidden inside the throttle plate itself. The owner would never see it unless he knew to pry off the cover and adjust it.
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Originally Posted by super20dan
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
limited jet screws I have seen....fixed jets...havent seen those...not to say that's not true, but I bet there is a replacement carb with no limiter caps and full adjustment for really cheap available.
I would never buy anything that had a carb that was not adjustable -how would that even ever work properly?
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
limited jet screws I have seen....fixed jets...havent seen those...not to say that's not true, but I bet there is a replacement carb with no limiter caps and full adjustment for really cheap available.
I would never buy anything that had a carb that was not adjustable -how would that even ever work properly?
Originally Posted by tundraotto
Originally Posted by 2K2AcuraTL
This is a very interesting thread.... youre making me reconsider my strict -1 gas can for each blend- required... 50:1 - 40:1 and 32:1
so would it be a realistic to shoot in the middle with a 40:1 and run all 3 types of OPEs on the same blend..??
Absolutely - run them all at 32:1 or 40:1
The caveot is that the carbs MUST be adjusted to run with the new ratio, otherwise you are leaving something at the table.
ok.. makes sense... but starting to adjust cabs is a little sketchy for me... are we talking adjusting the low speed or hight.. or both...??
my [ 10 year old ] Sthil FS38 was bogging down... tried adjusting the carb... didnt really work to my satisfaction.. I just finished replacing the carb on it.... works like new again..
i wouldnt mind using a 40:1 mix and running all my OPEs, and calling it a day.
Originally Posted by 2K2AcuraTL
This is a very interesting thread.... youre making me reconsider my strict -1 gas can for each blend- required... 50:1 - 40:1 and 32:1
so would it be a realistic to shoot in the middle with a 40:1 and run all 3 types of OPEs on the same blend..??
Absolutely - run them all at 32:1 or 40:1
The caveot is that the carbs MUST be adjusted to run with the new ratio, otherwise you are leaving something at the table.
ok.. makes sense... but starting to adjust cabs is a little sketchy for me... are we talking adjusting the low speed or hight.. or both...??
my [ 10 year old ] Sthil FS38 was bogging down... tried adjusting the carb... didnt really work to my satisfaction.. I just finished replacing the carb on it.... works like new again..
i wouldnt mind using a 40:1 mix and running all my OPEs, and calling it a day.
Originally Posted by super20dan
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
Thx.. so in your opinion... what are the risks involved if i were to switch to 40:1 on all my OPEs, without making any carb adjustments;
if I may, this is my arsenal...
50:1
2- weed-wackers [ Sthil and Husq]
1- chainsaw [ Husq]
all about 10 years old
40:1
1- [old] McCullough chainsaw [1980-ish]
32;1
1- very old Lawnboy [1970s]
carbs on many small engines have fixed jets and cannot be adjusted like in the past. I have around 100 2 cycle engines in my lawn biz and I split the difference at 40/1
Thx.. so in your opinion... what are the risks involved if i were to switch to 40:1 on all my OPEs, without making any carb adjustments;
if I may, this is my arsenal...
50:1
2- weed-wackers [ Sthil and Husq]
1- chainsaw [ Husq]
all about 10 years old
40:1
1- [old] McCullough chainsaw [1980-ish]
32;1
1- very old Lawnboy [1970s]
