3 saws to repair, 2 Stihls & 1 Poulan

[Coralillo Lo Pro]

I fixed up a cheap Poulan recently. Nothing much wrong beyond rotted fuel lines and primer bulb. The cheap consumer saws like Poulan seem to specialize in using fuel lines that rot within a year or two, 90 percent of what goes wrong with them. Otherwise though regarded as low value, they're a chainsaw, they work fine. Chain was utterly hopeless, first attempted sharpen didn't really improve it much. Then I discovered it had been sharpened back a lot probably with an electric grinder without the gullets being opened up at all and thus impossible to round file sharpen. I did a quick and dirty sharpen with chain grinding burrs in a Dremel and opened up the gullets and now the chain is razor sharp. But a new chain will also take care of it. Sounds very similar to the condition mine was in.

 

[Sub-arctic]

I fixed up a cheap Poulan recently. Nothing much wrong beyond rotted fuel lines and primer bulb. The cheap consumer saws like Poulan seem to specialize in using fuel lines that rot within a year or two, 90 percent of what goes wrong with them. Otherwise though regarded as low value, they're a chainsaw, they work fine. Chain was utterly hopeless, first attempted sharpen didn't really improve it much. Then I discovered it had been sharpened back a lot probably with an electric grinder without the gullets being opened up at all and thus impossible to round file sharpen. I did a quick and dirty sharpen with chain grinding burrs in a Dremel and opened up the gullets and now the chain is razor sharp. But a new chain will also take care of it. Sounds very similar to the condition mine was in.

I've sharpened chains before, but had limited success. I could get them sharp, but apparently sometimes I didn't get something right, because they wouldn't cut straight. I'm pretty sure the Poulan chain is ready for replacement. I'm hoping I can get both Stihls running well, then I'll probably sell the Poulan.

 

[Coralillo Lo Pro]

Sharpening evenly on each side can be tricky to achieve. Has been the frustration of many, certainly me for years, getting teeth on one side sharper than the other and having the saw not cut straight. With small chains that cost next to nothing, if they're more than half worn, often better off just grabbing a cheap new one. Also, my policy on low value saws if I'm repairing them for myself vs someone else is if there's compression and spark and I can get them to run decent, I don't look past that. Not worth my time on saws like that to get into crank seals, etc or worry about the state of the piston and cylinder. Beyond fuel lines and filter, a $10-15 aftermarket carb often gets the cheap saws running fine. Until it's a saw that costs more than $400-500 new, I rarely get much into seriously taking them apart, unless the P&C are easy to pull without dismantling much of the rest of the saw.

 

[dboyd351]

The bar is discolored along the bottom, near the back. It obviously got hot. I suppose that bar is no good, or soon will be due to the temper being taken out of it?

Don't worry about the bar. Flip it upside down, put on a new chain and let her rip.
I wouldn't sell it either. You won't get much for it. Just keep it as a spare backup or truck saw.
Sometimes you have a bar get pinched and you need a second saw to cut the first one free.

 

[Sub-arctic]

Don't worry about the bar. Flip it upside down, put on a new chain and let her rip.
I wouldn't sell it either. You won't get much for it. Just keep it as a spare backup or truck saw.
Sometimes you have a bar get pinched and you need a second saw to cut the first one free.

If I get both Stihls running I'll have a backup. I guess if I can't get much for the Poulan, it might be good to keep as a more disposable saw. If it got lost, stolen, or damaged, no big deal.

 

[Coralillo Lo Pro]

If I get both Stihls running I'll have a backup. I guess if I can't get much for the Poulan, it might be good to keep as a more disposable saw. If it got lost, stolen, or damaged, no big deal.

A go-to-hell saw is always useful to have for a variety of reasons. I even temporarily ruined a chain trenching some garden rows for my wife with one. The problematic sometimes working Stihl sounds like bad crank seals (doesn't idle well anymore when warm), but could be other things like a bad carb boot or maybe something else entirely. If you can get it going, a test you can try without a pressure/vac tester is spray some wd40 or carb cleaner around the boot and near the crank seals and see if the engine revs change at all. Regarding the compression tests, automotive testers rarely give accurate readings on small two stroke engines, mine always read 40 psi low, so I'd guess the compression is likely fine on all of them. As was said, you need to test a saw with known good compression to know how far off your tester is reading if it's not accurate. I got an inexpensive Lang TU21 small engine tester and that has proved a lot more accurate.

 

[singinwoodwackr]

I read that the 023 and 025 were built on the same chassis(?), and had thought a little about exchanging parts. I hadn't gotten too far on that thought yet though, I'm glad you suggested it. I did test the 023 for spark, and it looked like it was working pretty well to me. The air filter looked pretty clean, so it would seem to be a fuel problem. Last night I started trying to find out if it has a fuel pump. I'm guessing it does, maybe a diaphragm type? I hadn't found an answer yet. I supposed the carb could be gummed up with bad gas too. I have no idea how long it's been since it ran.
I had to look up impulse, I was not familiar with that term relating to engines. I infer from that, that it does have a diaphragm type fuel pump that runs off of impulse? I am familiar with those type of pumps.
I will remove the exhausts soon, and inspect what I can.
I've read that the Poulan is not a very good quality saw, but it has the best compression of the 3. I will put some time into it, if nothing else I will probably learn something from it.

021, 023, 025 are all interchangeable.
021,23 are $100 saws…in great shape. 025/250 are good for $200.
Unless you have spare pts and the skills to fix them they are disposable.

 

[J D]

A go-to-hell saw is always useful to have for a variety of reasons...

Sometimes having "trash" tools you're fully prepared to abuse to death can be invaluable... & occasionally you get some that just won't die. I've got an old Poulan 2300 that was half destroyed when I got it & I've given death over the years. Only repairs it ever gets are "bubblegum & duct tape"... thing just keeps chuggin along & at this point I'll probably be a little sad when it finally gives up

 

[Sub-arctic]

A go-to-hell saw is always useful to have for a variety of reasons. I even temporarily ruined a chain trenching some garden rows for my wife with one. The problematic sometimes working Stihl sounds like bad crank seals (doesn't idle well anymore when warm), but could be other things like a bad carb boot or maybe something else entirely. If you can get it going, a test you can try without a pressure/vac tester is spray some wd40 or carb cleaner around the boot and near the crank seals and see if the engine revs change at all. Regarding the compression tests, automotive testers rarely give accurate readings on small two stroke engines, mine always read 40 psi low, so I'd guess the compression is likely fine on all of them. As was said, you need to test a saw with known good compression to know how far off your tester is reading if it's not accurate. I got an inexpensive Lang TU21 small engine tester and that has proved a lot more accurate.

Thanks. I bought a pressure / vac tester, but spraying WD-40 on it while it's running sounds like a quick and easy test.
I guess a saw with a bad crank seal sucks air past the seal and runs lean, and maybe leaks worse when it's warm?
I know the former owner took it to a local shop at least a couple of times. The shop has been around for many years, so I would think they would know what they're doing, and would have checked the seals. Maybe not though.

 

[Coralillo Lo Pro]

I guess a saw with a bad crank seal sucks air past the seal and runs lean, and maybe leaks worse when it's warm?

Exactly. A little tear or puncture in the carb boot is going to let air in right away, so that's more often what causes it to run lean all the time with mysterious P&C scoring, rather than start okay and leak worse when it gets warm like bad crank seals. (Well, not always, flexing of the saw while in operation can cause the carb boot to leak worse.) The shop may have never run a pressure/vac test because as was noted about the value of the saws, what a shop would charge to replace the seals would probably about buy you a new one. I've never bothered taking apart a clamshell engine (all the small non-pro saws) because such saws are considered kind of disposable.

I know experienced repair guys can break a saw down completely in relatively short order, but I hate splitting a case unless I'm doing a total rebuild and you can't take the P&C off clamshells without splitting the case. It's easier than splitting the case of a pro saw, but still not something I can really be bothered with. That's why I say I only get into piston and cylinder and seals work on pro saws worth $500+. If it's not a fuel or ignition issue more easily fixed and runs well enough to cut a little while before acting up, I'd just designate it to backup saw category. Of course it would be good to get one of these saws dependable and not have them all be backup saws. I love my MS251 I got donated as a junk saw, needed a new starter recoil, oil pump worm gear, handle repair, and maybe a couple other small odds and ends, but nothing wrong internally and works like a champ now. My records show I did buy a $5.49 aftermarket ignition for an 021 023 025 this year but no idea what saw that was, maybe one of my repairs for my tree service neighbor on his MS250.

 

[Sub-arctic]

So in the case of the 025, the spark plug is very black with carbon. Is it relatively safe to assume it has no air leaking into the case?

 

[Michael E]

It's only safe to assume that the saw was running too rich and/or with too much oil in the mix. 50:1 is fine.

 

[Coralillo Lo Pro]

So in the case of the 025, the spark plug is very black with carbon. Is it relatively safe to assume it has no air leaking into the case?

Yeah, either running rich or ignition is failing. What Michael said. Doesn't rule out air leaks, but not the first thing I'd be looking for. A new plug is always a good place to start. Since both 023 and 025 share everything, it wouldn't hurt to get a cheap ignition in case one of them needs one, they cost next to nothing - https://www.amazon.com/PARTSRUN-Ignition-Chainsaw-0000-400-1306-ZF-IG-A00148-B/dp/B085BQF1MT
I've had people tell me Stihl ignitions rarely go bad and steer me away from that when it was the problem and an easy cheap fix. I had a veteran small engine guy tear my saw apart multiple times and tell me he really doubted my ignition was the problem in one of my first big saws, when it turned out the saw was infamous for its ignition problems. It's one thing a shop will never be able to diagnose easily if it's working but not quite right, and the only way to really know is switch out the ignition and see if it works better. Also one of those things that if it's failing, it changes the timing as it warms up and makes the saw run worse.

 

[Sub-arctic]

Today I got the chain that I ordered for the Poulan. I put it on and did just a little bit of cutting. I didn't give it a good test, but I think enough of a test. It cuts well as long as I don't get too aggressive with it. It kept running when I let it idle. Good enough for now at least. I probably shouldn't expect too much from it.
It's been unusually warm here, so I've been getting some things done outside instead of working on saws. I'll probably start looking at the 023 next, in a about a week. I'm glad to have one saw that seems to be working well.

 

[Coralillo Lo Pro]

Today I got the chain that I ordered for the Poulan. I put it on and did just a little bit of cutting. I didn't give it a good test, but I think enough of a test. It cuts well as long as I don't get too aggressive with it. It kept running when I let it idle. Good enough for now at least. I probably shouldn't expect too much from it.

Get some SeaFoam engine/fuel system cleaner and put a capful in each tank of gas you run in it. Like my Poulan, the carb is probably a bit dirty and doesn't always want to run at full power. I used to put it in my fuel for outboard motors but never occurred to me until recently to do it for chainsaws. Changed my mind about Poulan and Ryobi only being just poor fuel lines and carbs, maybe not so bad otherwise. Lightly used Ryobi bought new by my MIL a few years ago was having trouble starting the other day, finally got it going and revving and after a minute it stopped with a thunk and is totally locked up now. They're just plain cheap. Then again, who knows what her incompetent handyman did to it using it so can't totally blame the saw.

 

[dboyd351]

I'm really sorry you have one saw thats cutting with minimal effort expended on it and it is embarressing the 2 Stihls. Maybe you should just throw it away and start working on the two Stihls.

 

[Sub-arctic]

Get some SeaFoam engine/fuel system cleaner and put a capful in each tank of gas you run in it. Like my Poulan, the carb is probably a bit dirty and doesn't always want to run at full power. I used to put it in my fuel for outboard motors but never occurred to me until recently to do it for chainsaws. Changed my mind about Poulan and Ryobi only being just poor fuel lines and carbs, maybe not so bad otherwise. Lightly used Ryobi bought new by my MIL a few years ago was having trouble starting the other day, finally got it going and revving and after a minute it stopped with a thunk and is totally locked up now. They're just plain cheap. Then again, who knows what her incompetent handyman did to it using it so can't totally blame the saw.

Sounds like a good idea. It makes me wonder too if SeaFoam might do a lot for the 025. I know it hasn't gotten used much for the 5 years, and I seriously doubt that the owner stabilized the fuel.
Does anyone add Marvel Mystery Oil to their fuel mix? I know a number of people who do that for their plane engines, they claim it helps a lot to prevent valves sticking, and keep the crankcase clean. Those are 4 strokes though.
I will rarely use the saws, so I need to look into how to store them, whether I should just add a fuel stabilizer, or drain the fuel when I'm done, or ?

 

[Sub-arctic]

I'm really sorry you have one saw thats cutting with minimal effort expended on it and it is embarressing the 2 Stihls. Maybe you should just throw it away and start working on the two Stihls.

Well, hopefully I'll get the Stihl's running well at some point, then I'm sure they will be the preferred saws to use. At that time, the Poulan will probably sit, or go away. For now, I'll take the easy win and be happy with the Poulan.

 

[J D]

Lightly used Ryobi bought new by my MIL a few years ago was having trouble starting the other day, finally got it going and revving and after a minute it stopped with a thunk and is totally locked up now. They're just plain cheap. Then again, who knows what her incompetent handyman did to it using it so can't totally blame the saw.

Regardless of what the handyman may have done, a saw thats sat a lot & then doesn't want to start &/or run properly needs the fuel system/carb going over or you have a good chance it will be under fueling & then lean seize. In this case I'd be thankful it was a disposable saw & not something of real value

 

[Coralillo Lo Pro]

Sounds like a good idea. It makes me wonder too if SeaFoam might do a lot for the 025. I know it hasn't gotten used much for the 5 years, and I seriously doubt that the owner stabilized the fuel.
Does anyone add Marvel Mystery Oil to their fuel mix? I know a number of people who do that for their plane engines, they claim it helps a lot to prevent valves sticking, and keep the crankcase clean. Those are 4 strokes though.

My impression is MMO isn't really suited to 2 stroke engines, haven't seen much about people putting it in saws.