What oil is best? and what ratio?

[jakethesnake]

Original is my go to

 

[Moparmyway]

What ratio does that come out to. I may convert to just that I cooked a 346 not so long ago. Still a little but hurt over that one. I like the extra oil Oil girl was dry inside

I’ve seen some oils leave crankcases very dry at 5oz/gallon, and I’ve seen others leave pools of oil at that same ratio. I use the ones that leave oil.

 

[P.M.P.]

Blah blah blah

 

[RI Chevy]

What ratio does that come out to. I may convert to just that I cooked a 346 not so long ago. Still a little but hurt over that one. I like the extra oil Oil girl was dry inside

I just did some calculations, 5oz of oil to 1 gallon of fuel comes out to about 25:1.

 

[jakethesnake]

I’ve seen some oils leave crankcases very dry at 5oz/gallon, and I’ve seen others leave pools of oil at that same ratio. I use the ones that leave oil.

Have any trouble fouling plugs runnin that rich? I've noticed on my stock saws. If I let them idle to move brush Heavy smoke for a couple seconds. I let a guy borrow my saw it came back with oil in muffler. If I personally run them I don't get the residue as I am usually wide open or idle. After my 346 failed I've been running rich as hell. No measurement. Just add "enough" oil.
You run any stock saws or mostly all ported. I run 50cc up to 70 ish

 

[Moparmyway]

I havent replaced a plug in years and I dont have gooey exhausts either. I run the same 5oz/gallon in my 30cc saws as I do in my 90cc saws, my blower, weed whipper, trimmers, etc.

Just about everything I have is ported, except the blower

The hedge trimmer is the only one that has a wet exhaust, and I can live with that. 26cc's ........ I aint killing it

 

[jakethesnake]

I agree on the wet exhaust. I don't sweat that

 

[Greenerpastures]

Have any trouble fouling plugs runnin that rich? I've noticed on my stock saws. If I let them idle to move brush Heavy smoke for a couple seconds. I let a guy borrow my saw it came back with oil in muffler. If I personally run them I don't get the residue as I am usually wide open or idle. After my 346 failed I've been running rich as hell. No measurement. Just add "enough" oil.
You runny stock saws or mostly all ported. I run 50cc up to 70 ish

A few months ago I ran 37:1 in a 7900, it was a little
oily, but not worth talking about.
After a few tanks, I ran some 42:1, and it did not clear
up much, then after I got my tach, I retuned,
and to my surprise no more oil, and am still running
her on the rich side, she is set to 12000 max.
If I go up near 12450 the tack goes bonkers and I loose
the fourstroing.
When I have need to cut with her, I will likely be leaning her out a bit.
I set her up without the spark screen, and no oil, I though adding it would make big change, but the
tune neve budged, and thankfully no oil out the muffler, she should do well from here on in.
The book says 2500 for idle, and that is where she sits, I might up it if she bogs down in the low
before I would richen up the low, it seems plenty rich as she starts with 1.75 pulls on choke,
and fires up on two further pulls.
My Sindaiwa does not seem to care what mix I give her, again, she is easy to tune and that
seems to be the key to keeping oil at bay, you have to tune with this in mind.

 

[mdavlee]

A few months ago I ran 37:1 in a 7900, it was a little
oily, but not worth talking about.
After a few tanks, I ran some 42:1, and it did not clear
up much, then after I got my tach, I retuned,
and to my surprise no more oil, and am still running
her on the rich side, she is set to 12000 max.
If I go up near 12450 the tack goes bonkers and I loose
the fourstroing.
When I have need to cut with her, I will likely be leaning her out a bit.
I set her up without the spark screen, and no oil, I though adding it would make big change, but the
tune neve budged, and thankfully no oil out the muffler, she should do well from here on in.
The book says 2500 for idle, and that is where she sits, I might up it if she bogs down in the low
before I would richen up the low, it seems plenty rich as she starts with 1.75 pulls on choke,
and fires up on two further pulls.
My Sindaiwa does not seem to care what mix I give her, again, she is easy to tune and that
seems to be the key to keeping oil at bay, you have to tune with this in mind.

Those saws will run fine sitting on the limiter. It's a pain to tune

 

[Greenerpastures]

Those saws will run fine sitting on the limiter. It's a pain to tune

Exactly, I just needed to know where the limiter cut in,
now that I do I can lean out untill I hear it, no point in going any leaner after that, very distinct difference between the four stroking I now have, and when the limiter used to hit, limiter was way louder, un missable.
I found her easy to tune once I knew her limits.

 

[huskihl]

Exactly, I just needed to know where the limiter cut in,
now that I do I can lean out untill I hear it, no point in going any leaner after that, very distinct difference between the four stroking I now have, and when the limiter used to hit, limiter was way louder, un missable.
I found her easy to tune once I knew her limits.

Isn't a 7900 limited at 13,500? It's pretty easy to tell by ear in 2 second bursts wide open

 

[bwalker]

A few months ago I ran 37:1 in a 7900, it was a little
oily, but not worth talking about.
After a few tanks, I ran some 42:1, and it did not clear
up much, then after I got my tach, I retuned,
and to my surprise no more oil, and am still running
her on the rich side, she is set to 12000 max.
If I go up near 12450 the tack goes bonkers and I loose
the fourstroing.
When I have need to cut with her, I will likely be leaning her out a bit.
I set her up without the spark screen, and no oil, I though adding it would make big change, but the
tune neve budged, and thankfully no oil out the muffler, she should do well from here on in.
The book says 2500 for idle, and that is where she sits, I might up it if she bogs down in the low
before I would richen up the low, it seems plenty rich as she starts with 1.75 pulls on choke,
and fires up on two further pulls.
My Sindaiwa does not seem to care what mix I give her, again, she is easy to tune and that
seems to be the key to keeping oil at bay, you have to tune with this in mind.

Be careful with that Dolmar 7900. Rev limiter can complicate tuning and you can be dangerously lean and it may still sound likes it's four stroking.

 

[Keith Gandy]

 

[Cracker Boy]

View attachment 96721

Mine said comprimise so i bought 3 more and sold 1 does that count.

 

[Cracker Boy]

Of course she only knows about 2 of the 3. Of them and i got 2 more parts saws comin

 

[CoreyB]

Of course she only knows about 2 of the 3. Of them and i got 2 more parts saws comin

Parts saws don't count they are just parts. Lol

 

[Cracker Boy]

Parts saws don't count they are just parts. Lol

Good im safe lol

 

[Cracker Boy]

If i get busted i will tell her the boys on the forum said parts saws dont count.

 

[Greenerpastures]

Isn't a 7900 limited at 13,500? It's pretty easy to tell by ear in 2 second bursts wide open

Mine cuts in at aroond 12500,
the tach goes nuts, and the sound is something else.
I have her four stroking at 12000, I will see how she goes in the cut.
I deifinately can see me leaning the high much more.
But am only going to get 500 more before that limiter gets in the way,
it could be faulty, but I can't take a chance and cross it.

 

[Greenerpastures]

Be careful with that Dolmar 7900. Rev limiter can complicate tuning and you can be dangerously lean and it may still sound likes it's four stroking.

Thanks for the warning, I have her set to 12000 fourstroking,
so I should be safe, no room lean her out much more as she
definately goes on the rev limiter on the low side of 12500.
Just upped the low a little too, now I have a small seep of oil
at muffler after a few good revs, so am sure she is righ enough all round.

Thans, john