Nik's Poulan Thread

[Kensie1988]

I need to find out more about the cube carbs. Venturi is listed but are the idle and main nozzle discharge ports all the same size for a given venturi in a carb series? I would like to find out about stuff like that.

That is an excellent question that I don't have the answer too either. I imagine there would be a variation of both. I need to get my hands on an SDC-69 off a homelite 550 and take some measurements, because it has the 19.84 Venturi

 

[Hoggwood]

I could be wrong, but that SDC-80 might have the high speed check valve - 86532. If they get stiff/curl in the pocket, they will pull air into the idle circuit when coming down off throttle. Symptoms would be intermittent high idle or slow to idle down. Different reed properties could have changed the dynamics/response of that check valve.

I had to swap one on an xl-76 a couple of years ago. Did everything possible, but in the end, that was the issue.

Just a random thought if the carb does have the high speed check.

 

[Kensie1988]

I could be wrong, but that SDC-80 might have the high speed check valve - 86523? If they get stiff/curl in the pocket, they will pull air into the idle circuit when coming down off throttle. Symptoms would be intermittent high idle or slow to idle down. Different reed properties could have changed the dynamics/response of that check valve.

I had to swap one on an xl-76 a couple of years ago. Did everything possible, but in the end, that was the issue.

Just a random thought if the carb does have the high speed check.

I have no idea if there is a high speed check valve

 

[Kensie1988]

I could be wrong, but that SDC-80 might have the high speed check valve - 86532. If they get stiff/curl in the pocket, they will pull air into the idle circuit when coming down off throttle. Symptoms would be intermittent high idle or slow to idle down. Different reed properties could have changed the dynamics/response of that check valve.

I had to swap one on an xl-76 a couple of years ago. Did everything possible, but in the end, that was the issue.

Just a random thought if the carb does have the high speed check.

I'm not seeing the high speed check valve on the ipl

 

[Hoggwood]

#16 on the IPL - Nozzle assembly / Check valve?

 

[Kensie1988]

#16 on the IPL - Nozzle assembly / Check valve?

Yep, how would I go about checking to see?

 

[Hoggwood]

Pull the welch plug if you are doing a full kit. Seal a piece of Tygon around the screen. Should pass with mouth pressure and firmly check with vacuum. Perhaps it could be done via the high speed needle with the low seated. I just check them when the plug is out and I am cleaning the screen.

It is a real treat to change out the screen that comes with the kit if you need to. The check is below that in the pocket. The part comes pre-assembled with housing/screen and you seat it onto the check.

 

[Kensie1988]

Pull the welch plug if you are doing a full kit. Seal a piece of Tygon around the screen. Should pass with mouth pressure and firmly check with vacuum. Perhaps it could be done via the high speed needle with the low seated. I just check them when the plug is out and I am cleaning the screen.

Well the carburetor was NOS, but I'll check it out when I get the chance

 

[fossil]

I'm not seeing the high speed check valve on the ipl

I think #16 on the IPL. I do believe the cube carbs all have check valves on the high speed discharge. There seems to be two types. A mechanical one and a capillary one.

I could certainly be wrong though.

I found and issue on an HS-176 carb that was a nozzle check valve issue thanks to some help from Al Smith. The saw ran weird.
It would four stroke and then go lean but was running really rich at times. I have a couple more HS carbs with that issue.

 

[Kensie1988]

I think #16 on the IPL. I do believe the cube carbs all have check valves on the high speed discharge. There seems to be two types. A mechanical one and a capillary one.

I could certainly be wrong though.

I found and issue on an HS-176 carb that was a nozzle check valve issue thanks to some help from Al Smith. The saw ran weird.
It would four stroke and then go lean but was running really rich at times. I have a couple more HS carbs with that issue.

Well I'll check it out, luckily they still sell the complete high speed jet check valve assembly

 

[Cookie]

Speaking of 655’s, figured I’d post a couple pics of mine while it’s getting pulled apart and cleaned. Still need to do the fw side seal then reassemble. I don’t think the panels were ever off this thing. There’s barely a mark under them after cleaning. I’d love to find a nos Poulan Pro bar for it if anyone knows of one.

 

[Kensie1988]

Speaking of 655’s, figured I’d post a couple pics of mine while it’s getting pulled apart and cleaned. Still need to do the fw side seal then reassemble. I don’t think the panels were ever off this thing. There’s barely a mark under them after cleaning. I’d love to find a nos Poulan Pro bar for it if anyone knows of one.

View attachment 647149

View attachment 647150 View attachment 647151

There are some for sale on ebay

Or they may be Pioneer/Partner, I can't remember lol

 

[Cookie]

There are some for sale on ebay

Or they may be Pioneer/Partner, I can't remember lol

Been keeping an eye on there. There’s a couple, but prices are a bit nuts. Thx tho

 

[Kensie1988]

Been keeping an eye on there. There’s a couple, but prices are a bit nuts. Thx tho

It's a bit hard to find the Poulan Pro/Poulan bars sometimes. I bought a bar from little red Barn for my homelite super XL 925, it was listed as a generic 32" bar. Turned out to be a 34" Poulan Pro NOS bar. I called them because I thought they made a mistake. Turns out they didn't. They buy them by the pallet and the list them by what saws they fit. So if you contact them, they might can come up with one.

 

[Cookie]

It's a bit hard to find the Poulan Pro/Poulan bars sometimes. I bought a bar from little red Barn for my homelite super XL 925, it was listed as a generic 32" bar. Turned out to be a 34" Poulan Pro NOS bar. I called them because I thought they made a mistake. Turns out they didn't. They buy them by the pallet and the list them by what saws they fit. So if you contact them, they might can come up with one.

Is that what your 655 is wearing now ?got a pic ? Thx

 

[Kensie1988]

Is that what your 655 is wearing now ?got a pic ? Thx

Mine is wearing a vintage Poulan bar, the homelite still wears the Poulan Pro bar lol

You can see it here:

 

[Cookie]

Haha. Nice. This saw deserves a nice bar.

 

[Kensie1988]

Pull the welch plug if you are doing a full kit. Seal a piece of Tygon around the screen. Should pass with mouth pressure and firmly check with vacuum. Perhaps it could be done via the high speed needle with the low seated. I just check them when the plug is out and I am cleaning the screen.

It is a real treat to change out the screen that comes with the kit if you need to. The check is below that in the pocket. The part comes pre-assembled with housing/screen and you seat it onto the check.

So this is still bugging me, since I've never seen one in my mind it sounds very difficult to fix. But if I replace that whole check assembly, in theory, if that is my issue, then that should rectify it?

 

[fossil]

@Kensie1988

Here's a larger Walbro WB-2 carb you would find on a 100cc Homelite Super 650. Venturi is 23.83mm

Pics beside an SDC carb

 

[Cookie]

@Kensie1988

Here's a larger Walbro WB-2 carb you would find on a 100cc Homelite Super 650. Venturi is 23.83mm

Pics beside an SDC carb


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That’s a monster