# Poulan pb250 E problems



## wa5ngp (Aug 14, 2010)

I've got a Poulan PB250E combo string trimmer chain saw.
Carb Zama W32A 6YA

Here's a bunch of other numbers
2007 carb/us EPA PH2
7PWES.03224TM/:32CC TWC
07023N 102662-1 13:49
MOD PB250E 711814

not sure how relevant, looks like it was tested at 13:49 

The problem to begin with was that it would start, trip off choke and then run for like 2 seconds and then die.

I completely took apart the Zama carb cleaned it with brake fluid and put back together and get mostly the same result. Starts right up when choked, trips off (kinda automatically) and then runs a bit longer, say 5 seconds then dies. I can redo the whole sequence. The fuel runs thru the lines just fine. I'm thinking if I can somehow prevent that choke from totally dropping out I might be able to keep it running.

I've got new fuel hoses, 1 day old fuel that runs fine in my other toys.

I ground off the housing that surrounds the mixture screws in hopes of adjusting however it appears that they are thread locked in. Is that correct? Courtesy of EPA I assume?

Suggestions? Besides run away from Poulan?:drunk:

tks
don


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## geogrubb (Jul 28, 2006)

wa5ngp said:


> I've got a Poulan PB250E combo string trimmer chain saw.
> Carb Zama W32A 6YA
> 
> Here's a bunch of other numbers
> ...


Did you clean it with brake parts cleaner or brake fluid, brake fluid is not a cleaner. Have a good one. Geo


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## wa5ngp (Aug 14, 2010)

*I used brake CLEANER the non plastic attacking version*

I used brake CLEANER the non plastic attacking version. It was in an aerosol spray so it had some pressure to clean out the pathways.

I was able to keep it running by holding the choke partially closed so that tells me the jets are somewhat clogged. 

This thing is only 1 year old and was left sitting up after one usage. fyi, I didn't do that my friend did.

I think those jets are non removable. I noticed that there are no springs under them like "normal" cube carbs.

Since that pathway is apparently partly clogged I am thinking maybe to add some Sea Foam to the fuel to see if that clears it. However, I'm holding off on that as I'm concerned it may attack some plastic in the fuel path.

The other option is to take the carb appart again, identify the hole for the idle and main paths and spray more aggressive carb cleaner thru those paths. I was wanting to avoid doing that due to possible plastics inside the carb body.
don


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## John Lolli (Nov 3, 2005)

I am certainly not an expert as there are much more senior mechanics on this board - however here is what I have experienced over the years when a 2 cycle acts like yours. I am going to assume that you have cleaned the carb correctly.

1. Do a compression test. You need to have at least 90 psi.

2. Remove the muffler and clean the screen. While you have it off, look at the cylinder wall for scoring. There should be none or very little.

3. On Poulan/Craftsman 2 cycles there is a tendency for the cylinder bolts to come loose. Check this and if they are loose, remove them, pull the cylinder and check the cylinder gasket. If the gasket is bad, replace it. Put it back together using loctite on the bolts. Also check the piston for scoring and that the rings are free while you have the cylinder off. 

4. Remove the crankcase plug/cover and check the gasket. If it is bad, replace it. When re-installing the screws, use loctite. 

As a last note, I like to replace ALL the gaskets including the intake and carb gaskets when I work on these. Sometimes, the carb manifold will come looose as well especially on a Homelite.

Good Luck


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## geogrubb (Jul 28, 2006)

If it's only one year old it maybe covered by warranty. While it is running spray/dribble some brake parts cleaner behind the carb along the mating surfaces, if the engine tempo changes you have an air leak. Have a good one. Geo


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## wa5ngp (Aug 14, 2010)

*not removable jets?*

Tks for suggestions. My experience has been that if was running ok before then if it requires excessive choking to run then its gummed up in the jets. It makes sense. So I've fixed them by cleaning those jets. Problem with this one is that the jets seem to be threadlocked in place not allowing adjustment.

Maybe I should start another thread about how to loosen "permanently set jets" that these new 2 cycl engines have.

don


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## dehrhardt (Apr 1, 2009)

If you have no luck cleaning it again, this info might help.
I was unable to locate your model on partstree. If it is a PPB250E, there is no kit available for the carb. You can buy a new carb for around $23 plus shipping.


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## geogrubb (Jul 28, 2006)

If you are talking about the adjustment screws (H and L) I have never seen any that are permanently set, there are some special tools needed for the adjustments because of the EPA, there is a tiny spline, double d, pack man, etc, most people have found a work around for them. I would suggest visiting the Zama site www.zamacarb.com and look under the Service/Aftermarket tab, they have a lot of great technical info about their carbs. have a good one. Geo.


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## wa5ngp (Aug 14, 2010)

tks Geo,
I tried adjusting them but they are extremely tight. I was afraid that they would twist off so I decided to not push my luck. That was the reason for the comment about permanently set. They also don't have springs under them, but maybe that's just a cost reduction. tks for the link. I'll take a look.

Before buying a new carb I may apply a very small butane torch to the head of those adjustment screws (H,L) to see if that loosens them but that's a last resort. At this point its become a hobby, but after all this site is called "Hobbytalk".
don


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