Shop Products
Houzz Logo Print
jpswede

Poulan Chainsaw Won't Start

JPSwede
9 years ago

I have a 2 year old Poulan 4620AVX chainsaw that slowly died while I was cutting a tree down so I thought it had run out of gas. Unfortunately not. That was a week ago and I have yet to get it to even "turn over" once, aka "pop".

When I pull on the starter rope, there is no backlash if you know what I mean. It just spins. There is resistance, just no solid resistance like it's ever going to "kick" in. Again, the resistance just feels the same from the beginning of the pull to the end.

It is getting spark and gas so does the problem sound like a timing issue for some reason? It will also not pop once even with a little carb cleaner sprayed down the carb or spark plug hole with or without the choke on or off.

I also took off the muffler and the carb and used the carb cleaner and it still wouldn't even pop once.

The new plug is also slightly wet after using the carb cleaner and I've verified it is getting a spark at least when it's out of the saw so it's not the kill switch either.

I've checked for scratches on the piston and I didn't see any. I also did a thumb test for compression and it seems like it has good compression - at least it felt the same as my other identical saw. But I guess I should get it accurately checked soon.

And the only thing I haven't checked at all is the flywheel and any timing issues. An ideas on what to check/how to check that?

Thanks for any/all help!

Comments (31)

  • loger_gw
    9 years ago

    1. My thoughts would be compression (even though you gave it a prelim test) or muffler back pressure.
    2. Ck the flywheel key X Timing, Ck carbon or stuck ring X compression, Ck spark arrestor X restriction.

  • JPSwede
    Original Author
    9 years ago

    The muffler isn't on it so it's not a spark arrestor problem and that was very clean anyway. I think it's a compression issue since there doesn't seem to be much back pressure to it at TDC like my other saw. But I'll check the flywheel key next and report back. Thanks.

  • loger_gw
    9 years ago

    A good compression test compared should tell you something. In the past, my finger or thumb test has been a good preliminary w/o a gauge close. Basically I have not been able to hold the compression in a small engine that was good. The few that have not passed usually have shown why through the exhaust port vs pulling the cylinder.

  • JPSwede
    Original Author
    9 years ago

    The flywheel key was fine so I went out this morning and bought a compression testing kit and will be testing it tonight. It's the only thing left I think. Will let you know. Thanks.

  • loger_gw
    9 years ago

    Check/Match the depth of the threads. I have seen some adapter in sets that would hit some pistons. I always turn by hand first when in doubt.

    Good luck on the compression since you have not seen a reason to have bad compression. This could be interesting. Add a little oil if it's low to see if it will come up on 4-5 strokes. A little oil can indicate the rings are not sealing well.

    What grade of Poulan saw vs my 70,s S25 that have served me well vs todayâÂÂs Plastic.

  • JPSwede
    Original Author
    9 years ago

    Well good news/bad news on the compression testing. My first pull only produced 30 lbs of pressure, then by 5 pulls it was only up to 50 lbs. After 15 pulls it was up to 65 lbs but never got past that even after 50 pulls. In comparison, my good saw produced 60 lbs of pressure after the first pull and got up to 100 after 5 pulls. Btw, this good saw has started on the 2nd pull many times and it was at 90 lbs on my 2nd pull during the testing.

    I thought it felt like there wasn't the same resistance in the bad saw. So I now know why it won't start but I'd like to know why. I don't see any scoring but I can't see the whole piston of course. Is the piston ring just worn out now and needs replaced after just 2 years?

  • JPSwede
    Original Author
    9 years ago

    So I just did the oil test and the pressure did increase some. On the first pull it went from 30 lbs of pressure up to 45 and then to 60 after the 2nd try but then slowed down and ended at 70 lbs after 15 pulls. I also meant to say before that the top of the piston and the exhaust port looked normal. Some carbon but not excessive I don't think. And from what I can see of the walls of the cylinder, it looks fine too.

  • loger_gw
    9 years ago

    I put a piston/ring set in one of my S25 Poulans that seized/locked after hrs on a 100 degree day. That gave me approx another 10 yrs cutting 2-4 cords approx 20 years. During a PM I felt too much play in the rod bearing and retired it for parts (since I have 2 others with fewer hours). My first had a wrist pin keeper to come off after 10 years. It ruined the cyl which was too expensive vs replacing the saw.

    Approx how much time or cords did you have on the saw? I have averaged 2-4 cords since the mid 70s after cutting about 10 one season. Then not one the next due to a Hernia Surgery but had plenty wood.

    I doubt I will purchase another gas saw. IâÂÂm mainly working pre-cut to lengths 4-12âÂÂdia wood cut and left on the curbs for City Bulk Pickup monthly now. The contractors will cut/stack the wood to length knowing it will go fast or load you in the Old Neighborhoods. They chip/haul the brush and all is cheaper to the homeowner that takes that option. I have not needed a gas saw in two years (Thanks to my 14â Electric Mac) but I keep two serviced and ready.

  • JPSwede
    Original Author
    9 years ago

    I have only cut about 2 cords a year from May to September for the last 2 years so about a total of 4, maybe 5, cords on this one saw. To me, that doesn't seem like much since it was spread out over 5 mo's each year but maybe it is for this particular saw. Should I just bite the bullet and replace the ring and gaskets and see what happens? Most of the trees I am cutting down are dead but they are 12-15" in diameter and oak. Maybe my saw is too wimpy haha.

  • loger_gw
    9 years ago

    I would look at what you have invested. Poll the Pros here on whether it will take a rebuild or was it designed to be replace. I have just my limited experience rebuilding on the mid-grade saws. Pull the cyl to see if there is minor damage you could not see. See if the need is obvious and reasonable in needed parts cost.

    That was a simple evaluation or job and good experience (on my two S25 vs too many mowers etc). The 1st was not reasonable after 10 yrs on the 1st saw. Due the need to replace the cyl the keep wore into. The second had 10 yrs but just needed a Piston and Ring Set (50.00 vs 100.00 if a cyl had been needed). Most Of All! I like to know the cause if at all possible.

    Such as: I did use the 1st in 100 degree heat which could have had some influence on the keeper failing. I felt the 2nd failure had two factors, working in 100 degree heat (all ways noticeable hotter) and possibly not a good oil-mix. In the 70s 16:1 was recommended but I might have run 50:1 (from using left over 50:1 BoatâÂÂs Mix w/o making it 16:1+).

    Since the failures, I try and work when itâÂÂs cooler, monitor the engines gas or electric closer and use them shorter periods (mornings, 1-2 hrs above 70-80 degrees). Age has brought on A Natural Monitor. LOL!

    How old is your identical saw, approx cords or hrs of use and where were they built? IMO that was not good service, think if there could have been other conditions to influence the failure (bad fuel mix, bad bar/chain, over revving with no load, extreme heat and Etc).

  • Tex.H
    9 years ago

    i have a similar issue with my newish poulan. it starts and runs but as soon as i press the trigger to adjust idle it stalls dead.

    just got it last year it wouldnt stay running on my first attempt so i had it in to a repair shop..it ran ok for a couple of hours, now its doing this.
    any thoughts ?
    Tex

  • loger_gw
    9 years ago

    Tex,

    1. Approx how long are you storing without using? Are you using and storing with treated fresh fuel. I treat my fuel with Stabil and get a years use w/o a problem. I have heard untreated ethanol fuel will only work for 30 days. I have not experienced this personally.
    2. I have seen cases where restricted fuel filters would not allow good fuel flow.
    3. Ck all fuel lines for air tight fits and no cracks.
    4. Get a close Yardman or friend that use 2-cycles daily to spot check it. They usually have a good feel for problems.

    It might be a good idea to start a new post vs this one becoming confusing even though they are relates.

    Good Luck! Please share your results.

  • spotzie1
    9 years ago

    Ran last year but started acting up....this year did carb cleaning, carb gasket kit, new gas, new plug, after many pulls got it started...can get to idle for a little while.... tried adjusting H screw for high rpm...worked for a little while..at full throttle speeds up then slows down....saw even does some cutting for a couple of mins until it finally dies. Following other posts in this forum. Did a few of those steps... Checked piston for scoring..none, checked exhaust for carbon build...none but wire- brushed clean anyhow..removed plug...pulled 15 times full throttle, poured gas in opening..replaced plug...then pulled to try to start..... Let it cool down, sprayed carb cleaner in carb and after a few pulls finally started, revved up a little even did a little more cutting....had to keep adjusting H screw to keep it running high... then died again. Please someone tell what is wrong with this thing.

  • spotzie1
    9 years ago

    Ran last year but started acting up....this year did carb cleaning, carb gasket kit, new gas, new plug, after many pulls got it started...can get to idle for a little while.... tried adjusting H screw for high rpm...worked for a little while..at full throttle speeds up then slows down....saw even does some cutting for a couple of mins until it finally dies. Following other posts in this forum. Did a few of those steps... Checked piston for scoring..none, checked exhaust for carbon build...none but wire- brushed clean anyhow..removed plug...pulled 15 times full throttle, poured gas in opening..replaced plug...then pulled to try to start..... Let it cool down, sprayed carb cleaner in carb and after a few pulls finally started, revved up a little even did a little more cutting....had to keep adjusting H screw to keep it running high... then died again. Please someone tell what is wrong with this thing.

  • loger_gw
    9 years ago

    My Poland S25 saws were mid range @ 200.00+ mid 1970s. With no chainsaw experience X using, servicing or rebuilding I had a Gut Feeling that was the lowest quality I could expect some true service from or needed. I had good training and experiences at that time on 4-cycle mower, tillers, edgers and Etc.

    I had learned by then that quality came at a cost (not to mention the needed maintenance) and basically good or bad experiences started with the purchase. I was taught to clean, service and inspect the saws per few hrs of use to maintain the life of the Mid Grade Saw. This has worked!

    I recommend cleaning, servicing and inspecting or have it done if you expect power equipment to perform. Due to learning and experimenting, I have donated or traded too much labor vs one penny. Time on Mid Range or any equipment is not worth my time if itâÂÂs not worth the ownerâÂÂs time.

  • ewalk
    9 years ago

    Loger , let the gent Tex know that if his Poulan has a Walbro Carb to check the prefilter screen if a newer Keihien then he will have to do a concentrated fuel cleaner soak. As for Swede he probably has bad rings . Your Older Poulan had Chrome ring sets which lasted for yrs. The newer Poulan if ran hard will burn up a set a rings especially with lower grade oil.

  • loger_gw
    9 years ago

    Thanks Ewalk! My day-to-day hands on with Small Engines and current info were pushed out by computers in 1990. My personal interest vs the job has continued my interest almost weekly. With a much lower level of info on hand. This TX heat (vs your Cool) and slowing on Committed Volunteering has allows me to help search some needs (âÂÂAbove Basicsâ vs knowing since my past experiences are almost history).

    âÂÂHeat And AgeâÂÂ, are my new challenges during summers. Share More Of Your Cool Air. LOL !

  • spotzie1
    9 years ago

    well now my chainsaw won't even sputter even after priming it in the carb and down the sparkplug opening. I removed the carb to give it a good cleaning and found that the cylinder to adapter gasket is not complete and the seal for the carb adapter is torn....could those be my problems? Do I just need to replace those items and my chainsaw should work? If so where is the best place to obtain these parts? Thank you for your help

  • spotzie1
    9 years ago

    8/13/14 I took my carb off my poulan 3400 countervibe chainsaw again. Put the heavy metal pieces in carb cleaner and then sprayed the openings all out, cleaned and sprayed all of the gaskets and diaphram out and today I rebuilt the carb. I checked for spark, compression and fuel flow. All seemed good. The chainsaw did run for a while and I let it idle on its own hoping it would keep running. It would quit running and to get it to restart I had to hold the throttle open full and after numerous pulls it would sputter and finally re-start. But it will not start now and. Can someone please tell me what is wrong with this thing.

  • spotzie1
    9 years ago

    well by now I hope someone has read my previous posts. I finally got the saw to run and cut...for a while. Now its not starting or running at all again. Did the carb cleaning, checked for spark, compression thumb check, all gaskets checked..all good....carb to assembly came loose...checked gasket..cleaned area well and re-tightened both screws....this was the problem before...saw started and run briefly on full choke, full throttle then dies....tried half-choke full throttle...ran for a few seconds then died....now won't restart. Does anyone know what is going on with this thing? Why won't it run smoothly? What else can I check for?

  • spotzie1
    9 years ago

    well by now I hope someone has read my previous posts. I finally got the saw to run and cut...for a while. Its a Poulan 3400 countervibe. Now its not starting or running at all again. Did the carb cleaning, checked for spark, compression thumb check, all gaskets checked..all good....carb to assembly came loose...checked gasket..cleaned area well and re-tightened both screws....this was the problem before...saw started and run briefly on full choke, full throttle then dies....tried half-choke full throttle...ran for a few seconds then died....now won't restart. Does anyone know what is going on with this thing? Why won't it run smoothly? What else can I check for?

    This post was edited by spotzie1 on Mon, Sep 22, 14 at 10:23

  • spotzie1
    9 years ago

    my chain saw is a Poulan 3400 countervibe

  • spotzie1
    9 years ago

    my chain saw is a Poulan 3400 countervibe

  • spotzie1
    9 years ago

    Chainsaw started today....it took many pulls....ran long enough for me to adjust high speed rpm's and idle. Shut it off to put it all back together and of course could not get it to restart. Pulled and pulled and pulled. Tried carb spray in carb....nothing...didn't even fire or for that matter smell like gas. I was told to check the electrical system. So I took it all apart again and this time checked fly wheel, on/off switch for a lose wire, spark....all seemed fine. Reassembled the whole saw and again no start. Not even a wimper. Does someone know what it is that makes this Poulan 3400 countervibe not run smoothly if at all? Are these things actually repairable? Is it just junk and needs to be tossed off a cliff?

  • ewalk
    9 years ago

    Spot : Sorry I or someone else has not gotten back to you have been personally quite busy with landscaping out back . You should probably go back to square one and establish that you have adequate spark (Blue) . Then try a little starting fluid or mixed gas within the spark plug hole , just a squirt . See if it kicks . Otherwise if not check you compression 90 # is minimal for your unit . Actually 125 # is optimal for quick starting . You will have to pull over the saw 4-5 times for an accurate compression reading . Get back to us on you success or lack there of same ... E !

  • spotzie1
    9 years ago

    Hi ....I have blue spark. However I noticed that when I check for spark it is not consistent. So I checked the solid state ignition coil and it tested as working but I still wonder if thats the issue. Hope not because I can not find part number 530039093, the ignition coil anywhere on line...checked the spark plug too....and even though it was good I bought a new spark plug, plus put in a carb kit. Actually just had it running and cutting....but I had the saw apart and it would only run on half-choke and not at full speed. So I put the saw all back together and of course it will not even fire, sputter or start. I really wish someone could tell me what is causing this.

  • spotzie1
    9 years ago

    Hi ....I have blue spark. However I noticed that when I check for spark it is not consistent. So I checked the solid state ignition coil and it tested as working but I still wonder if thats the issue. Hope not because I can not find part number 530039093, the ignition coil anywhere on line...checked the spark plug too....and even though it was good I bought a new spark plug, plus put in a carb kit. Actually just had it running and cutting....but I had the saw apart and it would only run on half-choke and not at full speed. So I put the saw all back together and of course it will not even fire, sputter or start. I really wish someone could tell me what is causing this.

  • Richard Smith
    7 years ago
    last modified: 7 years ago

    I cut for about 4 hours Poulan saw I it lost power now wont start any help much appreciated..could plug go bad while in use ?

  • ssewalk1
    7 years ago

    Richard , It,s been a while since my last post on this thread (Ewalk) As for Poulans they are light weight saw unit . If you maintain them religiously you will receive adequate service . If not then they will give you headaches lol. They are designed for light cutting requirements. !st you must ensure clean fresh fuel with adequate fuel conditioner due to ethanol fouling issues. You have not indicated how often you cut or how old your saw is . They primary failing of the previous saws complaints within this thread are in my opinion weak ignition modules causing irratic spark . Other than that compression or lack there of will cause hard starting and loss of power during prolonged cutting. I would start with cleaning your carb since fuel starvation is a basic cause . Also ensure you have adequate blue spark prior to cleaning carb . You must service your air filter and fuel filter seasonally or as required dependant on the hours of use . To summerize , check fuel , plug , filters , compression and clean carb . If unit does not start get back to us ...Chow !... aka formerly Ewalk

  • loger_gw
    7 years ago


    ewalk the following
    thread and last statement says a lot. I
    will still come across your nice Barn Pic and the one that looked close to
    yours in color. “”Chow !... aka formerly Ewalk”” (October 29, 2014 at 2:31PM)

  • ssewalk1
    7 years ago

    Loger , The Newer Poulans components just don't seem to stand the test of time . The elect components and carbs seem to fail prematurely. Your old S-25 Model was rebadged Pioneer prior to Partner buying out the Pioneer Ltd. That Unit would cut all Day without a wimper . As for the Pic situation I gave this some further thought and it was Baymee another Forum Member from Pennsylvania that you are confusing me with . He had Wing Storage Barns that he utilized for his Fire Wood Storage that I recalled that he provided back a few yrs ago , for info purposes .... Is Tomplum still acrive on the forum ?...aka Ewalk !