How rich do you guys run your older saws?

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Everyone responding with oil ratios... I think he is asking high speed fuel / air ratio.
I run mine on the rich side. Clean up in the cut, but nowhere near "max" performance output. I like to leave a safety buffer.
That's EXACTLY what I was going for MacAttack, but also interesting to hear others chime in on Fuel Ratios, and I myself like to run the older saws rich at High Speed.
 
Hi,

I live in Nth Queensland Australia, where in summer it is nothing to see 36-38 degrees C with 80-90% humidity and everything in that temp under load starts to suffer. All the leading Arborist compaines (and I have asked ) up here regardless if they are using Stihl or Husqvarna run their saws anywhere from 25-30:1.

Now these guys use there saws all day and use them hard, they are not bothered if the saw smokes a bit or smells funny because of the burning oil. They are only interested in one thing, saw longevity.

Now I am not saying you should run your chainsaw at that, but if you are only using it for a weekend saw, for fire wood or a collector I think 35-40:1 is more than safe. I have friends and other collectors up this way who run their saws at 40:1 and that is exactly what I run my saws at. I have new saws and old vintage saws and they all get the same 40:1.

It is totally upto you. As long as your are using good quality oil and not using the saw day in day out commercially, anywhere from 35-45:1 is a good safe ratio.

Cheers

Justin
 
That's EXACTLY what I was going for MacAttack, but also interesting to hear others chime in on Fuel Ratios, and I myself like to run the older saws rich at High Speed.
A little rich can be the difference between a melted piston or a minor repair if your old saw gets an intake leak or a failing crank seal.
The downside?.... You might foul a plug. I'd take that any day!
 
The more saws I build and tune the more I learn that a warmed up saw has different fuel supply requirements than a cold saw, a saw that makes long cuts in big wood needs more fuel to not only run the engine but keep it cool. This is why its so important to tach tune then really run the saw for a full heat soak to readjust. I no longer care so much about a saw running rich during startup and warmup or runs perfect after warm up thats only been run unloaded. adjust it rich enough its self cooling under heavy use yet cleans up and runs strong but not lean or so rich it does not clean up in a cut or bogs out when revs.
 
I have an old McCulloch owners manual from about 1970. In the tuning section it suggested to tune the high speed needle based on performance in the cut, and not by RPM or by ear. Essentially, tune it for the best cutting power in a big cut. I've pondered on this approach many times and wonder if maximum performance in a cut always translates to optimal tuning...
 
I have an old McCulloch owners manual from about 1970. In the tuning section it suggested to tune the high speed needle based on performance in the cut, and not by RPM or by ear. Essentially, tune it for the best cutting power in a big cut. I've pondered on this approach many times and wonder if maximum performance in a cut always translates to optimal tuning...
I have noticed this too. Sometimes I tune by ear and err on the rich side. I'll then do a few test cuts. Often I have to lean it out a bit for best power.
 
This thread is hilarious....the guy asked how rich to run the fuel / air mixture on an older saw. He's gotten like 2 answers to his question, and about 50 oil ratios, lol.
 
I said 35:1 I usually mix a gallon of unleaded 92 octane with 3.5 ounces of oil, usually Echo oil, which I calculated a few minutes ago to be 36.57:1. I put it in everything I have which is 2 cycle...
But the OP asked about tuning tuning the carb, nothing about oil! :popcorn2:
 
But the OP asked about tuning tuning the carb, nothing about oil! :popcorn2:
Okay, on tuning the carb: On many of my saws I purchase a new carburetor and start out at factory specs, warm the saw up a bit then set the idle to just below where the chain creeps. I tune the top end so it will have just a bit of four cycling when wide open. I don't own a tach. If the saw will not idle with any consistency I do a vac/pressure test on it..
 
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