Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Poulan => Topic started by: Cut4fun . on April 09, 2015, 02:34:21 pm

Title: Check Valve poulan micro saws
Post by: Cut4fun . on April 09, 2015, 02:34:21 pm
Thought we better save more info by Tim aka fossil before it get buried again and takes forever to dig through to find other places.

fossil =  I suspect some of you may have Poulan Micro's with the oiler check valve which is located behind the clutch. They give up after some period of time as they have a duckbill check valve which dissolves and won't oil.

This will let you know how to renew the valve which is becoming difficult to find.

There is a duckbill and a brass bushing inside. I searched some time ago and someone had repaired them successfully.

The one I took apart looks like this. The screen is missing.

The duckbill goes in flange up followed by the bushing which is stopped by a shoulder in the body and then the screen which is MIA

I cleaned and reassembled the valve parts in the order in the above pic. The duckbill is Poulan PN 530026119 which is readily available.

As mentioned previously, I had filed the top off that valve to remove the screen so I had no room to put the screen back in. I'm not sure how much debris the screen keeps out as the three I have removed had clean screens. I guess I will see if I use the saw for some length of time.

A few notes.

When the bushing, which is a slight press fit goes in, make sure it is firmly seated against the duckbill. If it is not, air will leak back to the crankcase and no pressure will build in the oil tank.

I peened the bushing / valve body to keep the bushing in place.
If I do another I'll pop the rolled lip back with a shaped drift so I can put the screen back in.
Some other member(s) mentioned that they used some JB Weld to put the screen back on but I was a little reluctant as I wouldn't want it to fall off and end up in a bearing.

If you haven't run one of these before make sure you release the pressure in the oil tank by unscrewing the cap or it will keep oiling until the tank pressure bleeds off.

It works great.

Title: Re: Check Valve poulan micro saws
Post by: Eccentric on April 09, 2015, 03:24:53 pm
That is indeed good info to save.
Title: Re: Check Valve poulan micro saws
Post by: Cut4fun . on April 09, 2015, 03:30:37 pm
That is indeed good info to save.

I might have put it in a thread here already too. I just cant remember anymore.    :-[
Title: Re: Check Valve poulan micro saws
Post by: countryhog on April 10, 2015, 09:48:54 am
I saved that post in a Word document. hopefully it is attached.
Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on April 20, 2015, 10:25:35 pm
I wish I'd known this a few weeks sooner. I threw away the bad check valve when I replaced it, not knowing it could be repaired.
Great write up, Thanks
Title: Re: Check Valve poulan micro saws
Post by: 3000 FPS on April 20, 2015, 10:44:33 pm
I remember when Tim first posted that.   Good info especially since the check valve is NLA.
Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on April 21, 2015, 06:26:40 am
The only thing that could be a real pain is trying to roll back the peen that holds the screen. I remember looking at that area and I can't envision how that could be possible. I'd like to hear/see how it's accomplished the first time. Someone here has to have an old bad one laying around. Give it a go.
Title: Re: Check Valve poulan micro saws
Post by: Cut4fun on April 21, 2015, 01:23:51 pm
My 2000 I bought new in 1994 has yet to have this problem (lucky I guess). Saw still gets used by my dad. 

Only thing that went bad was the coil. I ended up back in the day putting a homelite super 240 coil in it.
Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on May 08, 2015, 05:18:00 pm
Well I just tried dis-assembling one like the above instructions and it's a lot harder then it appears.

#1- trying to roll back the lip that holds the screen is very touchy. When I tried to pry the roll over up, it would break off. I got most of it up a little but like I said it'll break off if you try to go too much w/it. After breaking off about 1/3 of it during the process, the screen was loose enough to get out. I have to believe the rest will break when I try to crimp it again.  We'll see.

#2- the so called brass bushing was not in mine. If there is a bushing, I don't know how to get it out. It has to be a very tight press fit. I might have an earlier version that don't have the brass.  Mine looks like all the same material. I can feel a small ridge under it but I gave up trying to remove it for fear of destroying the valve. I even tried the drywall screw method, no dice.

I have a couple duckbills ordered, so when they come in we'll see where this takes me. 
Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on May 13, 2015, 09:42:05 pm
Update:
I finally got it apart and re-assembled. My bushing was steel not brass. Must have been an earlier version. I filed the crimp off (I don't think it would have helped having it anyway). Used my propane torch to heat up the outside a little, while also using the short leg of a allen wrench that fit in the hole to pry up. Popped up easy then.
Cleaned it all up w/brake cleaner. Inserted the new duck bill and put a little RED Loctite on both mating parts and tapped the bushing tight with a drift pin. 
The only messy part was putting the screen back on with JB weld. When/if I do another one, I'll put the JB Weld around the perimeter of the valve body, and push the screen into it.

I hope this helps anyone else wanting to re-build the check valve. After you've done one, you see what works and what don't, it's really easy. I got the duckbills from my Husky dealer for $1.49 each.
Title: Re: Check Valve poulan micro saws
Post by: 3000 FPS on May 13, 2015, 10:30:34 pm
Update:
I finally got it apart and re-assembled. My bushing was steel not brass. Must have been an earlier version. I filed the crimp off (I don't think it would have helped having it anyway). Used my propane torch to heat up the outside a little, while also using the short leg of a allen wrench that fit in the hole to pry up. Popped up easy then.
Cleaned it all up w/brake cleaner. Inserted the new duck bill and put a little RED Loctite on both mating parts and tapped the bushing tight with a drift pin. 
The only messy part was putting the screen back on with JB weld. When/if I do another one, I'll put the JB Weld around the perimeter of the valve body, and push the screen into it.

I hope this helps anyone else wanting to re-build the check valve. After you've done one, you see what works and what don't, it's really easy. I got the duckbills from my Husky dealer for $1.49 each.

Thanks for the report.  Good job.
Title: Re: Check Valve poulan micro saws
Post by: Al Smith on May 14, 2015, 05:14:52 am
Good info .I never did know how those things oiled .

I've only got one,an early 1.9 cube with that system .Plus it has a thumb button .Neat little saw .It was my climber before I got the 200T Stihls .
Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on December 20, 2016, 09:59:09 pm
Just an update to my previous post.
I've done several of these now, and have found that a just a very small touch of Aviation Permatex to the duckbill side shoulder when installing it will guarantee a airtight fit. I like to tap the bushing snug but not so tight that I may mess up the small shoulder. After rebuilding one I still didn't have the proper sealing when testing it. I took it apart and added the Permatex, reassembled it and problem solved. I did let it cure over nite before installing it.

I think the screen is more safety net to contain the check valve part/parts if they fail, from having direct access to the crankcase then being a filter.
Title: Re: Check Valve poulan micro saws
Post by: Cut4fun . on May 09, 2018, 09:06:59 am
@Todd Loosli   a member here and as has them FS too.   18 shipped. 

Just wanted to save a poulan check valve he made before it gets buried and lost.


Title: Re: Check Valve poulan micro saws
Post by: ChipsAhoy on May 09, 2018, 04:01:34 pm
Fantastic, that is ingenious.  8)
Title: Re: Check Valve poulan micro saws
Post by: Eccentric on May 10, 2018, 05:07:05 pm
Cool.  I'd much rather pay him $18 for a newly made check valve assy (with a fresh new duckbill within) than pay an eBay parts scalper $30+ for an NOS valve that might well decay and fail shortly after instalation.
Title: Re: Check Valve poulan micro saws
Post by: Super360 on January 07, 2020, 07:57:44 am
Here is a rebuild of one i did. I just used a sander to sand down the filter.