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There's a duck bill valve under that brass plug that's turned to goo. Clean the goo out and put a Poulan duck bill valve in. Valve, spring, plug.

Poulan PN 530026119. Flange on the valve goes in first.

View attachment 673423

With respect. That is the correct # for my 40 year old Pro Mac 10-10 [MOD 600014U] Ser # 12-83470. I ask because I was At A highly Recommended Parts store on Long Island and was told no chance to get the cap or any parts that will work. Enclosed is a Pic of the cleaned dissembled cap.
Note I can't copy the entire owners manual, but can scan a page or two if anyone needs specific info.
 

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Either the green Poulan duckbill or the red Homelite (69451 or Stens 610-345) will work with the brass insert. Most shops that charge by the hour could not afford to mess with repairing a fuel cap for an old saw. I've spent 30 minutes to an hour (or more) getting one to work properly and who would be willing to pay for that?

Get the Poulan or Homelite valve and put it together. Sometimes the valve needs to weep a bit to wet the lips before it will seal properly.

DSC02560.JPG

Mark
 
View attachment 674280 View attachment 674281 Will this type air filter fit my older 10-10A?

The hard air filter will not work in place of the flexible one with the rubberized inserts. If you look closely you will see the AF on your saw has a bump out to clear the choke, the hard filter in the second photo does not.

Sorry for the delay, here's a pic of the cap with aluminum plug.View attachment 674284

joeymt33 was able to take one apart by drilling out the insert, but then you would need to make a new insert. I have not been successful removing that aluminum insert to replace the duckbill valve. They look like you should be able to pull the insert out of the center but I haven't come up with the secret yet.

Mark
 
The hard air filter will not work in place of the flexible one with the rubberized inserts. If you look closely you will see the AF on your saw has a bump out to clear the choke, the hard filter in the second photo does not.

Mark

Is there anyway to referbish the one in the saw? It is in physical good shape just some of the felt is missing exposing the screen. I thought about trying to sew a piece of cloth over it through the screen and material.
I have put a new bar and chain on it. Rebuilt the carburetor and installed new fuel line and filter. Installed new spark plug and put bucking spike on. I took it apart and blew out all the old saw dust. I cleaned the points, coil, and flywheel. Just wanting to cut some wood but afraid to get dirt back in the carburetor.
This was my grandfather’s old saw my dad just gave me that he just dug out of the barn. He said it was the first gas saw he ever used.
 
Either the green Poulan duckbill or the red Homelite (69451 or Stens 610-345) will work with the brass insert. Most shops that charge by the hour could not afford to mess with repairing a fuel cap for an old saw. I've spent 30 minutes to an hour (or more) getting one to work properly and who would be willing to pay for that?

Get the Poulan or Homelite valve and put it together. Sometimes the valve needs to weep a bit to wet the lips before it will seal properly.

View attachment 674270

Mark

Mark,

It looks like the spring sits inside the fuel cap first, but fossil stated that the duck bill goes in first and the correct order is:

The duck bill goes in first. Flange against the cap, next the spring over the body of the duckbill (seals the valve against the cap), and last the brass plug

It looked to me that it would be cap, spring, duck bill, brass plug when I pulled it apart to clean it.

So which is correct? And does one (Stens or Poulan) work better than the other?
 
Thanks guys. Just ordered the Poulan duckbill valve and a Gas cap "cork" gasket from E-Bay [ different vendors. Will let you know how they work.
And now another Dumb question . Like I said she is 40 years old, no idea how many years it sat . Got it running on the old stuff. [ major smoke]
Now with new gas 89 and Tanaka 50 to 1 mix. Then added a bit more because Mac. called for 40 to 1 at the time.
Runs good, cut some small stuff. I get an oily residue on the exhaust side. [ no muffler , just an open exhaust port.] NORMAL ? or to much oil.
Thanks again.
 
Ditto.

They're also prone to bar oil leaking into the crankcase if the pump is a little loose or doesn't have the spring clip added to assist in making a tighter seal between the pump body and the case. Usually not a big deal but will be noticeable primarily by some smoking and occasionally the symptom you describe.
 
You will like a good running PM55.

Mark

Week ago picked up a PM55. Just had the time tonight to give it a once over and fire it up. At first it wasn't taking any thottle and bogging bad, 1/8 turn richer on low speed screw and it woke right up. No high speed adjustment on these carbs what's everyone think of them? Looks, sounds, and feels like it'll be a nice saw to run.
20180920_224245.jpg 20180920_225536.jpg
 
Week ago picked up a PM55. Just had the time tonight to give it a once over and fire it up. At first it wasn't taking any thottle and bogging bad, 1/8 turn richer on low speed screw and it woke right up. No high speed adjustment on these carbs what's everyone think of them? Looks, sounds, and feels like it'll be a nice saw to run.
View attachment 676035 View attachment 676036
I have a couple 55's I enjoy running em cuz they always start and run.. Easy to fix but I do put a H/L carb on.. I like to fiddle with the high to make sure it's rich enough
 
I have a couple 55's I enjoy running em cuz they always start and run.. Easy to fix but I do put a H/L carb on.. I like to fiddle with the high to make sure it's rich enough

Do you change out the tank so you can get to the screws? I've got a spare h/l adjustable sdc carb, but don't see how'd you get to the screws unless I change tank or drill holes in side of airbox?
 
Don't change the carburetor, McCulloch did a good job of selecting the correct jet for those saws unless you are located in some extreme altitude.

Same for the SP125 saws, they will never be lean due to carburetor adjustment.

Mark

Great to know Mark, thank you. Hopefully I'm gonna put it to some wood before weekend is out and report back.
 

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