40:1 or 50:1 mix on 372XP

[Andyshine77]

This is a topic that will I guess never get resolved there are the 50 & north to 1 believers & the other end the 40 & south to 1 group Both side quote X # of years trouble free use with their particular mix, & some take to task the posters that differ from their way of thinking I think it's a run what suits & you are happy with & any different mix they like let them carry on I have given up quoting why I run the mix I do & now adopt the do as you like to mix ratio's.

With 99% of stock saws you are absolutely right, 50:1 will provide adequate lubrication in most cases. The 372 is an exception, more oil is a must.

 

[HuskStihl]

I actually avoid premium e10. Around these parts, premium will sit in the tanks a lot longer than regular. I run 87 e10 with good oil at 32:1. I view that as cheap insurance as my main saw is a ported 385 (similarly "under-bottomed" to the 372), and when it's working, it's generally working hard.

 

[Full Chisel]

I actually avoid premium e10. Around these parts, premium will sit in the tanks a lot longer than regular. I run 87 e10 with good oil at 32:1. I view that as cheap insurance as my main saw is a ported 385 (similarly "under-bottomed" to the 372), and when it's working, it's generally working hard.

Good point, I had not thought about that...

 

[GrassGuerilla]

I actually avoid premium e10. Around these parts, premium will sit in the tanks a lot longer than regular. I run 87 e10 with good oil at 32:1. I view that as cheap insurance as my main saw is a ported 385 (similarly "under-bottomed" to the 372), and when it's working, it's generally working hard.

Absolutely true about premium sitting around longer. Especially outside of grass season. Summer months premium turns over at nearly three times the volume it does in winter according to the manager of my regular gas stop.

 

[ArthurB]

It is a known fact, adding more oil slightly increases engine temperature. The difference you saw was caused by a change in air fuel mixture, or it is simply in your head. Different fuel, and environmental changes will cause the mixture to change, but it was not cause by simply adding more oil.

I think you may be confusing the impact on running temperature of the air:fuel ratio, with the impact of friction

Increasing oil would in theory mean proportionally less fuel, and therefore a leaner mix - and this would in theory mean a higher running temperature - but to observe this effect you would need to displace far more fuel than would be the case when changing the oil:fuel ratio - there's bugger-all oil involved - so this effect is not seen

What is more important is the friction in the motor when running at sustained high revs - eg when sectioning large hardwood trunks - in this situation, increasing the oil from 50:1 to 35 or 40:1 reduces friction to the extent that there is a marked reduction in running temperature - this is a well-known result, and one that I have just confirmed through discussion with our local dealer

The bottom line is that the 372XP (and perhaps the friction characteristics of this motor are particularly sensitive to oil:fuel ratio) will run cooler at a higher oil:fuel ratio, and that this is recommended by dealers if using the saw for sustained high-input work

 

[CoreyB]

I compromise and run 42.5:1 why .5? Because I mix 3oz to one gallon at a time. Lol
I love oil threads they are lots of fun.
I also run vp 40:1 sometimes. It smells like the races and that makes me smile and pizz rev even more.

 

[Andyshine77]

I think you may be confusing the impact on running temperature of the air:fuel ratio, with the impact of friction

Increasing oil would in theory mean proportionally less fuel, and therefore a leaner mix - and this would in theory mean a higher running temperature - but to observe this effect you would need to displace far more fuel than would be the case when changing the oil:fuel ratio - there's bugger-all oil involved - so this effect is not seen

What is more important is the friction in the motor when running at sustained high revs - eg when sectioning large hardwood trunks - in this situation, increasing the oil from 50:1 to 35 or 40:1 reduces friction to the extent that there is a marked reduction in running temperature - this is a well-known result, and one that I have just confirmed through discussion with our local dealer

The bottom line is that the 372XP (and perhaps the friction characteristics of this motor are particularly sensitive to oil:fuel ratio) will run cooler at a higher oil:fuel ratio, and that this is recommended by dealers if using the saw for sustained high-input work

No confusion whatsoever, and the vast majority of us here agree, dealers usually know very little to nothing when it comes to saw performance. With proper tuning more oil will have little to no effect on friction. Proper tuning is the key here, as most don't even know what that is, let alone how to do it properly.

In fact more oil not only slightly raises combustion temperature, it can also allow more heat transfer "which is a good thing", but again it can raise measurable external engine temps slightly. With proper tuning you will not see a big difference in a factory saw, and certainly not one you can tell without taking an actual temp reading. In the testing Timber Wolf did many moons ago, I believe the largest difference was around 10°F If you see a drastic difference in temperature, something other than the oil is at play.

Anyway that's my input have a good one.

 

[Rio95]

I think this thread will confirm what Andyshine77 is saying. The video is no longer available (so it seems), but the results are clear - 32:1 runs hotter than 40:1 or even 50:1, and makes less power.

http://www.arboristsite.com/communi...1-vs-40-1-vs-50-1.276534/page-15#post-5300597

There is a lot of info in that thread, most of which is just splitting hairs. Personally I run 40:1, because it gives me that little safety factor incase I don't put in quite as much oil as i intended.

 

[Gypo Logger]

If you can smell fumes, the mix may be too fat or the saw may be too rich on the carb. run it at least 13,500 out of the wood.
I have a 372 BB that makes the trees piss their roots. My saw is so loud that the neighbours called the cops on me, but then again it was 11:30pm on a Saturday night when I was doing said sawing, so you cant really blame them for being disgruntled, but they soon got over it and ended up with the last laugh when the cops finally apprehended and tazered me.

 

[Westboastfaller]

With 99% of stock saws you are absolutely right, 50:1 will provide adequate lubrication in most cases. The 372 is an exception, more oil is a must.

well I'm 20yrs late, is it still a must?

 

[Andyshine77]

I think this thread will confirm what Andyshine77 is saying. The video is no longer available (so it seems), but the results are clear - 32:1 runs hotter than 40:1 or even 50:1, and makes less power.

http://www.arboristsite.com/communi...1-vs-40-1-vs-50-1.276534/page-15#post-5300597

There is a lot of info in that thread, most of which is just splitting hairs. Personally I run 40:1, because it gives me that little safety factor incase I don't put in quite as much oil as i intended.

He later added different oils. H1R was one of the only oils that made less power @ 40:1/32:1, most every other oil made more power at the richer ratios. The heat difference is there, but it's within the margins of error in this test. IMHO. The testing done by Timber Wolf was done in the early 2000's and the info was lost during the site hack. TW used a sensor in the exhaust port to get accurate and reliable readings.

 

[Andyshine77]

well I'm 20yrs late, is it still a must?

Yes!! If not yourself and the generations that follow you, will all parish if you refuse to run 32:1 in your 372's.[emoji12]

 

[Andyshine77]

Really the 372 issues some had were with saws used for limb work. Likely too many rpm's caused the the bulk of the failures. 32:1, proper tuning to lower rpm's and in the end a revlimiter all seemed to help. If you want to really run your 372's 32:1 is a good idea IMHO.

 

[Westboastfaller]

Yes!! If not yourself and the generations that follow you, will all parish if you refuse to run 32:1 in your 372's.[emoji12]

lol...
So you have a 372 voodoo saw that you are going to poke pins into and fix me once and for all. Don't! OK or I'll call you Andyslime..lol
I'll meet you guys in the middle. I started to run 40/1 a few months ago. I'll take the experts advice on ported saws.
I believe it was late August early September 1996 when I got my first 371
I had the main bearing go early once in a 2008 Simonized, I ran the saw over 100f weather and in the winter I had the cooling fins plugged solid and cooked the top end at -36 C then cooked a crome BB kit so maybe there may have been a fragment in the bearing? I wear the saws out before the top or bottom end. OEM top ends have never been an issue other than that one incident. 50/1 was good for this chassis for 20 yrs in ported saws. 40/1 may not make a difference to me but may likely be better in a different application.

 

[Andyshine77]

lol...
So you have a 372 voodoo saw that you are going to poke pins into and fix me once and for all. Don't! OK or I'll call you Andyslime..lol
I'll meet you guys in the middle. I started to run 40/1 a few months ago. I'll take the experts advice on ported saws.
I believe it was late August early September 1996 when I got my first 371
I had the main bearing go early once in a 2008 Simonized, I ran the saw over 100f weather and in the winter I had the cooling fins plugged solid and cooked the top end at -36 C then cooked a crome BB kit so maybe there may have been a fragment in the bearing? I wear the saws out before the top or bottom end. OEM top ends have never been an issue other than that one incident. 50/1 was good for this chassis for 20 yrs in ported saws. 40/1 may not make a difference to me but may likely be better in a different application.

Everyone's millage will vary.

 

[ArthurB]

No confusion whatsoever, and the vast majority of us here agree, dealers usually know very little to nothing when it comes to saw performance. With proper tuning more oil will have little to no effect on friction. Proper tuning is the key here, as most don't even know what that is, let alone how to do it properly.

In fact more oil not only slightly raises combustion temperature, it can also allow more heat transfer "which is a good thing", but again it can raise measurable external engine temps slightly. With proper tuning you will not see a big difference in a factory saw, and certainly not one you can tell without taking an actual temp reading. In the testing Timber Wolf did many moons ago, I believe the largest difference was around 10°F If you see a drastic difference in temperature, something other than the oil is at play.

Anyway that's my input have a good one.

Well, I guess it's sad for you that your dealers don't know much

Can't speak for the whole country, but the two Husky dealers here that I've dealt with here have both been very proficient

That said, theory is interesting up to the point where it disagrees with practical reality - and then you begin to understand that the theorist is probably missing some part of the picture - I can see that I'm not going to convince you of the truth of this one, but the fact remains that increasing the oil ratio has rectified the problem I had with an overheating 327xp - this done at dealer's recommendation - advice they give out routinely - no more hot saw - happy customer - period ...

 

[Little Al]

I think this thread will confirm what Andyshine77 is saying. The video is no longer available (so it seems), but the results are clear - 32:1 runs hotter than 40:1 or even 50:1, and makes less power.

http://www.arboristsite.com/communi...1-vs-40-1-vs-50-1.276534/page-15#post-5300597

There is a lot of info in that thread, most of which is just splitting hairs. Personally I run 40:1, because it gives me that little safety factor incase I don't put in quite as much oil as i intended.

Why is it that the 2 smoke tuning "guru's" produce & publish numbers that indicate/prove that more oil in the the mix produce a motor that will run with more revs/power the optimum mix being in the region of 18/20 to 1 "Bell'"s book giving a good coverage

 

[HuskStihl]

lol...
So you have a 372 voodoo saw that you are going to poke pins into and fix me once and for all. Don't! OK or I'll call you Andyslime..lol
I'll meet you guys in the middle. I started to run 40/1 a few months ago. I'll take the experts advice on ported saws.
I believe it was late August early September 1996 when I got my first 371
I had the main bearing go early once in a 2008 Simonized, I ran the saw over 100f weather and in the winter I had the cooling fins plugged solid and cooked the top end at -36 C then cooked a crome BB kit so maybe there may have been a fragment in the bearing? I wear the saws out before the top or bottom end. OEM top ends have never been an issue other than that one incident. 50/1 was good for this chassis for 20 yrs in ported saws. 40/1 may not make a difference to me but may likely be better in a different application.

Hey dumbass! Bringing real-world production falling experience into an oil thread, and then implying that not running magic motorbike oil at fatty ratios won't kill a saw dead in a week, is not what we do here! Take your 20 years of west coast production falling experience with ported huskies somewhere else!

 

[blsnelling]

I think this thread will confirm what Andyshine77 is saying. The video is no longer available (so it seems), but the results are clear - 32:1 runs hotter than 40:1 or even 50:1, and makes less power.

http://www.arboristsite.com/communi...1-vs-40-1-vs-50-1.276534/page-15#post-5300597

There is a lot of info in that thread, most of which is just splitting hairs. Personally I run 40:1, because it gives me that little safety factor incase I don't put in quite as much oil as i intended.

Why is it that the 2 smoke tuning "guru's" produce & publish numbers that indicate/prove that more oil in the the mix produce a motor that will run with more revs/power the optimum mix being in the region of 18/20 to 1 "Bell'"s book giving a good coverage

Little Al, you are correct. Way too many assumptions and false conclusions were made in that testing to put much of any value on it. The one conclusion that can be drawn from that testing is that H1-R does some weird stuff, not typical of most oils.

 

[rogue60]

I actually avoid premium e10. Around these parts, premium will sit in the tanks a lot longer than regular. I run 87 e10 with good oil at 32:1. I view that as cheap insurance as my main saw is a ported 385 (similarly "under-bottomed" to the 372), and when it's working, it's generally working hard.

What does the ''Bad'' sitting in the tanks longer than the regular gas do to a saw? serious question what does it do that's so bad?..Anyone got any pics or something??... Come on guy's lets see it the bad Gas carnage?.
Or we just talking melted fuel lines and saggy carby diaphragms in that case don't use fuel with ethanol in it I guess (Yawn)....