Poulan 4200

[Chuck Spitler]

I am attempting to help a friend with an older 4200 not a chain brake model. It is leaking from the gas tank vent. Which is a 3/8 the hex head fitting screwed into the top of the gas tank. Is there supposed to be a duck bill or someone the inside?

 

[hotshot]

I am attempting to help a friend with an older 4200 not a chain brake model. It is leaking from the gas tank vent. Which is a 3/8 the hex head fitting screwed into the top of the gas tank. Is there supposed to be a duck bill or someone the inside?

Yes, they rot out. Item 23 (530023166) is the DB valve & they put a piece of filter foam over it to help keep the crap out.

 

[cbfarmall]

Easiest vent in the world to repair.

 

[Chuck Spitler]

Yes, they rot out. 530023166 is the DB valve & they put a piece of filter foam ocer it to keep the crap out.
View attachment 1236626

Thanks for the reply. The IPLs that I was able to view on line were very sketchy and hard to read/see clearly. I was just able to down load a better IPL and it looks like it called for a 23166 check valve which is replaced by a 530023166 and or a 530026119. I am going to attempt to install one tomorrow. It looks to me like it would slip onto a smaller diameter tube that protrudes out of the the bottom of threaded hex shaped fitting. I assume that the duck bill will point down into the tank.

Thanks again
Spit

 

[hotshot]

Correct, tip points into tank, lets air in.

 

[Chuck Spitler]

So I fixed the vent with a new duck bill and I found that the fuel line has shrunk and it also leaks from around the line where it passes into the tank. The old line is a clear plastic/vinyl and is an odd size. I was able to insert the shank end of a 9/32 drill bit into the hole and a 19/64 would not fit.

The IPL calls for a part number 21022 and or bulk number 8136. I have not been able to get a hit on either number. The closest size of a Tygon that I can find is a 5/16 of 3/16 id. The shank on the carb and the fuel filter measure 1/4. The barb ahead of the shank is even bigger.I haven't tried this size yet and I would need to order some to try it. I am wondering if the 3/16 of will stretch over the barb and be able to be slide down the shank and actually fit??

Is there someone out there who has changed this fuel line and can advise me what fuel line they used.

I found some 5/16 x 3/16 vinyl tubing I bought a couple of feet and cut an inch off and have it soaking in gasoline, in order to see what gas does to it. My common sense says the vinyl tubing won't hold up. I have not tried to get the 5/16 line through the 9/32 hole...but I am hoping that the line can compress a 1/32 of an inch and be able to be pulled through the hole. This saw is 40ish years old and the hole in the tank is into thick cast metal that the tank is made out of. So its not a thin plastic tank that the line needs to be drawn through

Any and all input welcome

Spit