Tzed250
Addicted to ArboristSite
I think that is the first time I read that on this site.
I've probably mentioned it ten times in this forum...
.
What would cause this?
- Thread starter blsnelling
- Start date
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I've probably mentioned it ten times in this forum...
.
And I've seen it at least twice before, excluding this time.
the westspartan
Addicted to ArboristSite
Good morning guys,
I agree on all points. I always give her a cool down period, though probably more like 45 seconds (that will now change to a couple minutes). Since the above mentioned incident, I am much more strict about not runnig fuel older than a month and a half. I also dump the whole mix in the Mazda's tank(seems to run a little better when I do this though I make sure I have a half tank to a gallon of mix in the car). The only thing I have been doing significantly different than these suggestions is running 50:1 instead of 38:1. That will also now change.
Thanks for the input. It is nice to get a chance to see what you have been doing wrong without it causing any real damage. It must be a Christmas miracle! hahaha
Great thread guys.
Coupla ideas to add to the mix.
Cool down needed after milling?
If the 441 runs extra hot especially when milling then a proper cool down period becomes extra critical. With a Temp gauge on my 880 I note that it takes a full 2 minutes after milling to come come down to idle temp. If the temp is too high it will sit there for a long time cracking lube and caking it onto the hot surfaces. I'm setting up my small mill to take my 441 so I'm now thinking Temp gauge for that as well.
Gas:
If even a few ounces of bad/sour batch are left in the can then adding any new fresh stuff will makie go off faster and continue to go off every time more is added. Every time I go milling I dump the residual (yet two stroke mix and all) into the subaru and start with completely fresh gas and mix.
Milling mix. I'm using 38 +/- 2 : 1 on my saws. < 30:1 makes me feel sick and covers my chaps with black greasy gunk that I cannot wash out.
I don't think it's just one thing but a combination of several factors.
I agree on all points. I always give her a cool down period, though probably more like 45 seconds (that will now change to a couple minutes). Since the above mentioned incident, I am much more strict about not runnig fuel older than a month and a half. I also dump the whole mix in the Mazda's tank(seems to run a little better when I do this though I make sure I have a half tank to a gallon of mix in the car). The only thing I have been doing significantly different than these suggestions is running 50:1 instead of 38:1. That will also now change.
Thanks for the input. It is nice to get a chance to see what you have been doing wrong without it causing any real damage. It must be a Christmas miracle! hahaha
Well, this night owl is finally back among the living. Time to port match and mod the muffler.
the westspartan
Addicted to ArboristSite
opcorn:
I take the Subaru to the gas station to get the fresh gas. After I put the mix in the tank, I fill my fuel cans and then top up the Subaru tank with gas as well
I know some guys will not agree with this, but if it where me and I was using a 441 for milling I wouldnt hesitate to use a 20:1 oil ratio with a high end synthetic oil.
Each oil is different, but MX2T is very clean at 16:1 when loads are high.
Also in regard to break in with synthetic oil. I have used synthetic for break in for years. I know of not one two stroke OEM that recommends dino oil for break in. on the contrary synthetic is used as factory fill in many 4 cycle motors and all the major snowmobile OEMS recommend synthetic for their two cycles.
I think the idea that synthetics do not allow an engine to break in is largely based on the idea that they have greatly different film strength than dino oils. They do not. Their benefit in a two cycle is their ability to have high film strength base stocks that still burn with out leaving deposits.
Each oil is different, but MX2T is very clean at 16:1 when loads are high.
Also in regard to break in with synthetic oil. I have used synthetic for break in for years. I know of not one two stroke OEM that recommends dino oil for break in. on the contrary synthetic is used as factory fill in many 4 cycle motors and all the major snowmobile OEMS recommend synthetic for their two cycles.
I think the idea that synthetics do not allow an engine to break in is largely based on the idea that they have greatly different film strength than dino oils. They do not. Their benefit in a two cycle is their ability to have high film strength base stocks that still burn with out leaving deposits.
neutral4x4
ArboristSite Operative
Be careful using such high oil ratios. Since oil is thicker than gas, you'll have to retune your carb so that you don't run lean. It's usually a bad idea to run too much oil. When the gas vaporizes in your engine, that cools the engine. with less gas in the mix, your engine is going to run hotter not cooler.
Yes, you will need to re-tune the carb to ensure your not running too lean. The changes are very minimal IME.
And once the carb is tuned properly the amount of gas going through the engine is the same.
20:1??
I get running it rich, but that's just plain silly.
I get running it rich, but that's just plain silly.
Is it?
Consider that most cart racers run their air cooled two strokes at 16:1.
For a everyday work saw 20:1 isnt needed but when using a 70cc strato charged saw for milling I dont think 20:1 is out of line at all.
Of course I am not speculating as I have actually ran two cycle motors at 20:1 with quality oils and I know they operate cleanly and smoke free given the loads are appropriate for the ratio used.
neutral4x4
ArboristSite Operative
Really? Most kart racers I know are running 50:1. They go to 40:1 for break in. I've seen some drivers go as far as 100:1 (which I wouldn't chance). Thats with high quality synthetic though. Synthetic oil doesn't break down as easily as dino oil and therefore is better for lubrication. Most chainsaws run 32:1 simply because a typical home owner doesn't use high quality oil. Most don't even know the difference.
In case you don't believe me about the synthetic holding up at higher temps, look up 2 stroke kart racing videos. Right before the race starts, the drivers are all revving their engines up to really high rpms. They have to clear out all of that unburnt synthetic in their exhausts so that they have optimal performance on the takeoff.
Yes. Google up KT 100 oil ratio.
FWIW Yamaha recommends a 25:1 oil ratio for the KT 100, but most racers run 16:1 as the motors make more power and last longer.
And the smoke you see while free reving doesn't have anything to do with synthetics not combusting. It has to do with engine load and temperature.
Your assumptions about synthetics not breaking down as easy as dino oil is a bit of a blanket statement as well and its not even close to the truth. Truth is one of the main advantages of a synthetic two cycle oil is their ability to combust without leaving residue/carbon build up.
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neutral4x4
ArboristSite Operative
Why are they revving the engines? Why not just let them idle? They have to blow out the unburned oil.
You can only fit so much premix between the piston skirt and the cylinder wall. After a certain point (about 40:1) it doesn't help any more.
As for an engine running 16:1 being more powerful... how do you figure? A fuel with a higher viscosity doesn't atomize as well and gives you a more incomplete burn resulting in lower power. Running too much oil is going to make your rings stick, you'll foul plugs really fast, and you'll be running leaner (unless you compensate with jetting, which is going to make you foul plugs even faster). That stuff isn't as bad as a lean seize, but you won't lean seize on 40:1 if you jet correctly.
On a side note: most kart racers rebuild the top end and replace the plugs every so many races, so they can really run whatever they want. Heck some guys still stick with castor oil. Go ahead and run 16:1, at least you'll know what the problem is when your rings carbon up and your plugs foul.
I am not going to argue with you and not for lack of targets! Most of what you have posted on this topic is completely false.
When you have BTDT get back with me........ Its not speculating after you have done it...
When you have BTDT get back with me........ Its not speculating after you have done it...
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BTW here is what a piston ran at 20:1+ looks like. Looks pretty clean to me.:monkey:
More oil = More power and protection to a point.
Here is an old article, but I feel is still very relevant.
http://www.bridgestonemotorcycle.com/documents/oilpremix6.pdf
In my other 2 cycle engines I like to run an oil manufactured in the 40:1 range for synthetics (give or take) and richer on non synthetics. I have a buddy that flies UAV's with 2 strokes in the same cc range as saws. His company has tested just about every oil out there. When you spend over $150,000 on the cameras in these planes and have at least 10 in the air at one time 24/7 you don't need engine oil related failures.
Here is an old article, but I feel is still very relevant.
http://www.bridgestonemotorcycle.com/documents/oilpremix6.pdf
In my other 2 cycle engines I like to run an oil manufactured in the 40:1 range for synthetics (give or take) and richer on non synthetics. I have a buddy that flies UAV's with 2 strokes in the same cc range as saws. His company has tested just about every oil out there. When you spend over $150,000 on the cameras in these planes and have at least 10 in the air at one time 24/7 you don't need engine oil related failures.
Wild Knight
ArboristSite Guru
Posted a few comments relative to Brad's find here:
http://arboristsite.com/showpost.php?p=1977923&postcount=42
http://arboristsite.com/showpost.php?p=1977923&postcount=42
Where or what is the name of that thread, only one frame of pictures and comments showed up with your link.
I might be able to add some additional informations base on my own findings and findings from a hundred thousand or so hours of run time results.
Some might not believe what I say but it will at least be something to discuss.
I might be able to add some additional informations base on my own findings and findings from a hundred thousand or so hours of run time results.
Some might not believe what I say but it will at least be something to discuss.
