chainsaw woes ~ bad gas?

muldoon · January 31, 2011, 09:40:12 PM

I have two saws, stihl farmboss 029 (roughly todays ms 290) and a stihl ms 170. About a month ago I was cutting some brush and canopying some trees and the little saw was working fine. When I went to pick it up I pulled and pulled and pulled with nothing. I went to the other saw, topped it off in gas and bar oil, and tried to start it. Same thing, pulled and pulled and pulled. I have never had any trouble with either saw, I am 99.99% certain the gas went sour. I had a 2 gallon tank of 50:1 mix that was about 8 months old, had been using it on and off and this was the end of the tank.

I have never worked on these saws or their internals, never really needed to. I have worked on lawnmowers and edgers and of course cars. I am nervous about disassembling the carb on these little things because of all the screws and plastic moldings and little parts. I am thinking my plan is this. dump the gas, mix new gas. pull the spark plug, try to start it a few times with the plug out, if the plug looks fouled replace it, otherwise just put it back in. Add some seafoam to the new mix, gas it up and try to start it up.

Does anyone have any advice to try on top of that plan? Like I said, I am nervous about getting deep into disassembly on them.

MountainDon · January 31, 2011, 09:53:51 PM

I'd say new plug, new gas/oil and then if it doesn't start and run good take it to the shop. Some of those are difficult to get into being so small and all.

If I remember to empty the tank and run mine dry I never seem to have problems. When I forget or let it slide for a couple months I sometimes have issue. But I almost always run Stabil in my chainsaw gas even when I'm pretty sure I'll be using it more or less several times a week. That seems to help a lot. I rationalize the extra cost of the Stabil as saving me money on not having shop service or anguish over the PITA part.

Dang! I think I better check the saw in the garage tomorrow.

January 31, 2011, 10:11:25 PM

Quote from: muldoon on January 31, 2011, 09:40:12 PM
I have two saws, stihl farmboss 029 (roughly todays ms 290) and a stihl ms 170. About a month ago I was cutting some brush and canopying some trees and the little saw was working fine. When I went to pick it up I pulled and pulled and pulled with nothing. I went to the other saw, topped it off in gas and bar oil, and tried to start it. Same thing, pulled and pulled and pulled. I have never had any trouble with either saw, I am 99.99% certain the gas went sour. I had a 2 gallon tank of 50:1 mix that was about 8 months old, had been using it on and off and this was the end of the tank.

I have never worked on these saws or their internals, never really needed to. I have worked on lawnmowers and edgers and of course cars. I am nervous about disassembling the carb on these little things because of all the screws and plastic moldings and little parts. I am thinking my plan is this. dump the gas, mix new gas. pull the spark plug, try to start it a few times with the plug out, if the plug looks fouled replace it, otherwise just put it back in. Add some seafoam to the new mix, gas it up and try to start it up.

Does anyone have any advice to try on top of that plan? Like I said, I am nervous about getting deep into disassembly on them.

Sometimes Muldoon...you can get away with this trick. Pull the spark plug. Turn the saw upside down and dump all the gas. While it's still upside down, pull the starter rope a dozen or so times while holding the trigger wide open.

Turn it right side up and ill it with good gas. Try to start it. Sea Foam helps.

fishing_guy · January 31, 2011, 10:58:15 PM

Ditto on the Seafoam.

The first saw I owned was a Craftsman. It worked well for a year, and then one day I couldn't start it for anything. I ended up getting A Husky 455 for a project I was doing, and forgot about the Craftsman.

Fast forward 2 years. I was cleaning the garage and found the Craftsman. For giggles, I threw a good slug of seafoam in the saw. 3 pulls later it started right up.

Snake oil or not, I'm a firm believer.

cmsilvay · February 01, 2011, 08:57:02 AM

Check the fuel filters before you refill them They sit on the tanks on the end of the intake hose. For some reason my stihls give me the same problem unless i use the stihl mix.

February 01, 2011, 01:46:11 PM

All my saws are Dolmars and I still use the stihl mix. It's that much better than anything else I've tried.

MushCreek · February 01, 2011, 04:48:09 PM

A friend brought me his Stihl to look at- wasn't getting fuel. His fuel line was....gone! Melted! It turns out the booze they call fuel these days is very unfriendly towards fuel systems. All that was left was the fuel filter, rattling around in the tank, and brown sticky goo in the bottom of the tank.

ajbremer · February 01, 2011, 06:41:39 PM

Never use ethenal...unless:
http://www.forestnet.com/TWissues/August08/chainsaw.pdf

MountainDon · February 01, 2011, 08:24:19 PM

Can anyone actually find gasoline without ethanol added?

Does anyone know if white gas, Coleman fuel, works in a small engine? It stores very well.

I miss the "old days" when the local service station sold white gas, kerosene, bulk motor oil, etc. from barrels in the back room.

February 01, 2011, 09:49:52 PM

check with your local airport. Some airplanes have a STC (supplemental type certificate) that allows them to use auto gas in their airplane. The gas can not have ethonal in it. If there is any non blended gas available thay would know about it.

Shawn B · February 01, 2011, 11:31:23 PM

I read in a preparedness book to store the highest octane available, around here that is 91. The two reasons the author gave was:
1. Higher octane gas is more stable...does not break down as fast
2. Most 91 octane has little to no ethanol, which draws moisture and can gum up fuel systems.

peternap · February 02, 2011, 03:40:56 AM

As mentioned Don, small airports are good sources if you can talk them into filling up a can for you. That isn't always easy.

I don't know about other states but in Va, there are ethanol districts that surround Cities. The further from a city, the more likely you will find ethanol free gas. I have to look hard though.

ajbremer · February 02, 2011, 06:30:41 AM

There are gas stations around where I live that sell gas with no ethanol in it. Just get the highest octane.

MountainDon · February 02, 2011, 10:33:09 AM

Here everything has ethanol and all year now not like it was a few years ago when it was only added in winter. The nearest small )easy access) airport is a good drive. Maybe need to phone them and see.

February 02, 2011, 10:40:59 AM

Quote from: MountainDon on February 02, 2011, 10:33:09 AM
Here everything has ethanol and all year now not like it was a few years ago when it was only added in winter. The nearest small )easy access) airport is a good drive. Maybe need to phone them and see.

Just be careful and tactful about how you approach them Don. Since the Oklahoma city bombing, everyone has been seeing the sky fall when you ask if you can get a few gallons of gas.

muldoon · February 03, 2011, 09:46:36 PM

Thanks for all the ideas and knowledge posted here. I am "working from home" tomorrow due to winter weather tomorrow and plan to mix up some new gas and see what I can do with the saws. Will post back results afterwards.

muldoon · February 04, 2011, 04:36:32 PM

Got them both running again. new gas, new plugs, a bit of seafoam. The big saw sounds like the horse it always has been. But I still have a problem with the little one.

When I was last using it, it bogged down and stalled as I was trimming very small branches (no heavy load). The engine went to low rpm and the chain stopped turning. After about 5 seconds it stopped and never started back. Until today after the tuneup. It ran at low rpm about 10 seconds and died. I looked it over and noticed a bind where the chain wraps the sprocket. I took it apart and cleaned it up and put it back together. It runs again, low rpm, but the chain does not spin. Taking it apart a few times I find it is acting like the chain brake is engaged. If I have chain and bar off, I can disengage the brake and the sprocket spins. If I put the chain and bar back on it seizes up again.

I cleaned it up with simple green and put it back together a few times with no success. I think a trip to the sthil shop is in order for the brake... unless any of you guys have ideas to try?

bayview · February 04, 2011, 07:32:58 PM

Muldoon:

Does the chain work well in the bar when it is not connected to the saw? Maybe the bar is bent . . . Or the rpm's are to slow to engage the chain . . .

/.

Don_P · February 04, 2011, 08:43:19 PM

How does the engine run without the bar? There is a small fine screen inside the carb that can get fouled occasionally as well.

muldoon · February 04, 2011, 10:45:36 PM

bayview- The chain will spin on the bar when I have the bar off. I don't think anything is wrong with the bar.

Don- The engine does not leave a very low rpm with or without the bar. Without the bar, the sprocket spins, with the bar it does not. Even giving it full throttle, it does not rev up at all in either configuration. It is not like it stalls or anything under throttle, it doesn't react to the throttle at all.

I see what both of you are saying about the rpms being too low to spin the chain. ...

- 10 minutes later -

Yep. the throttle linkage has come off the carburetor. That would certainly explain the low rpm and lack of functionality. After a few minutes I got it back on and it fired right up and ran good. Thanks a bunch guys.

February 04, 2011, 11:15:21 PM

I'm glad it worked out for you.

I have had a number of craftsman chainsaws. With good luck until the last one I purchased about 2 years ago. The bar would flex, allowing the chain to come off continuously. No kidding! Every 5-10 minutes. I changed it out for an Oregon bar and chain. . . And the chains plastic tool-less, adjustment for the chain is a piece of c . . . !

I will definitely purchase a better saw in the future. Stihl?

/.

ajbremer · February 05, 2011, 07:05:15 PM

Efco is a great saw! (I have the 16" MT4000 model - cost me about $275.00). 5 year total guarantee, 14,000 RPM's, great oiler, always starts, etc. Here's one of the larger ones:

http://www.efcopower.com/Sezione.jsp?idSezione=769&idSezioneRif=441&titolo=MT7200%20&%20MT8200%20Chainsaws

(Warranty is no good if ya use ethanol though)

OlJarhead · February 05, 2011, 07:19:11 PM

Strange -- did you fix it? I haven't read the whole thread.

I routinely use gas that is that old and older in mowers and saws. Supposedly gas is ok (today) for 6 months to a year -- but a year is supposed to be pushing it however I've used gas older then that without stabil and it was fine.

Today I put stabil in any gas I'm leaving 6+ months but try to use by one year -- with Stabil I beleive you are likely safe for 2+ years. (though I think they only say 1)