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262XP maybe a goner!

Started by SwingOak, March 15, 2008, 12:58:33 AM

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SwingOak

Hi folks - I'm new here.

I've been poking around for a bit, and this seem like a good place to ask this question: I was bucking up some Norway maple today - a big tree behind the house that was around 120 years old and over 36" DBH. Anyway, I had just installed a new chain, a Stihl RSC3, and was breaking it in. I'm still tweaked Stihl doesn't make my favorite chisel chip Rapid Super in 3/8" pitch anymore...

I wanted the RSC but they were out, so I had to get the green link. (BTW bore cuts really easy - I had to try it out)

Anyway - I must have hit something in the log like a nail or something, because it gave up on running through the log and revved high, signs of a dull chain and low gas level in the tank.

So I touch up the chain and top up the tank, I'm running Husky oil in Super unleaded gas at 50:1. I buck for another 10 minutes or so, when I musta hit another nail or something and my cut rate dries up again. The saw revs up high, I'm at full RPM trying to finish the cut and then it just dies out. A fair amount of smoke is coming off the outside of the motor now. Well that's never happened before. So I give it a pull or two, and it won't restart.

At least it pulls, although it feels funny - sort of mushy. I'm thinking something screwed up somewhere, maybe I burned up a reed valve, or maybe it's the ethanol in the gas?

Anyway, I bought this 262XP saw in 1994, and have cut tons of wood with it, never had a problem, and it always barks on the first pull. I've got a smaller Stihl and an Echo climbing saw, but I just love the Husky.

What do you folks think the problem might be? I'm going to get some new gas in the morning and mix up a fresh batch, I'm hoping it will start. If it doesn't, I guess I''ll have to buy another saw. That's a different post I think...

Dave Shepard

Welcome to the Forum! Too bad your first post is about a dying saw. We have plenty of chainsaw people here to help you out. Hope it isn't a total loss.


Dave
Wood-Mizer LT40HDD51-WR Wireless, Kubota L48, Honda Rincon 650, TJ208 G-S, and a 60"LogRite!

Cut4fun


SawTroll

If the P&C is shot - that saw is well worth a rebuild!
Information collector.

SwingOak

Well if it needs a rebuild, it's going to get one. It's a good saw. I was going to check it out today, but I went fishing instead. I didn't catch anything either.  :-[

So I came home, put the boat away, and split some wood for a while. Putting axe to wood always makes me feel better.

It's supposed to be rainy/snowy tomorrow so it will be a good day to see "what's what" with the saw. Anyone know if there is a shop manual for it?

Kevin

There is a manual available for the 262, it's a good saw and worth a rebuild.
Baileys has the piston, head and rings.

Cut4fun

Lurcherman, I just sent you a 262 IPL in a link in a PM. You will need Adobe Reader to open the file, just like most of them out there. Enjoy.

SwingOak

Thanks! It's printing now...  :)

SwingOak

I fought with my saw all afternoon. I took it mostly apart, pulled the muffler off, and looked inside. There was some light scoring on the piston and cylinder on each side of the exhaust port. Maybe that's normal, I just don't know. I cleaned the whole saw, put everything back together, and nearly wore my arm out tying to start it. I didn't measure it, but there seemed to be good compression.

I think maybe the plug is fouled, so I go to put my spare in and wouldn't you know it - I'm already using my spare, (oops) so I head out back and clean it with my spark plug cleaner. Back in the saw, and pull pull pull again, Not even a cough.

I take the plug out again, and it's wet with gas - I check for spark, and I've got a good spark. What the???? Gotta be the gas. So I head out to the gas station, fill the truck 'cause I know it's just going up again tomorrow, and mix up exactly one gallon of 89 octane and one bottle of Husky oil. 50:1.

Hey, and guess what? The saw fires right up, more or less. I just have to adjust the idle and throttle screws a bit. I sharpen up the chain, and have at the big log again. 1/3 of the way through, I hit a bolt or something (saw the sparks) but kept sawing. I get most of the way through the log, and hit something else- another nail or bolt or rock or something, and bwahhhh - the say dies out again. Smoke is coming off the motor again.

So I go set it on the tailgate of my truck to finish smoking and cool down. When I go to give a few pull about 1/2 hour later, it almost sounds like a squeaky/scraping noise coming through the muffler, and my one decent feeling compression now seems not so good.

Me thinks I scraped up the piston and cylinder.

So next step is to order a few parts and have a go at rebuilding it.


beenthere

Lurcherman
Hope you get it fixed.

I don't quite understand the routine you have of hitting something in a log, and then you continue sawing....apparently with a dull chain.   ::) ::) ::)
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

SwingOak

Quote from: beenthere on March 16, 2008, 07:28:14 PM
Lurcherman
Hope you get it fixed.

I don't quite understand the routine you have of hitting something in a log, and then you continue sawing....apparently with a dull chain.   ::) ::) ::)

Well, it was still cutting. It was still cutting the second time I hit something, but with only inches to go, I figured I'd finish it out.

That's why.

Yeah, I know better. Maybe it wasn't the best decision, but I don't think that caused the problem.

And as I said, this tree was behind my house, and there is probably 100 years of clothesline hooks, dog chains, and hammock ties in it. Which is why it's not a saw log, it's firewood.

Jason_WI

50:1 is too lean for that saw. We mix 40:1 no matter what the manual says. We don't live in California!

Norwood LM2000, 20HP Honda, 3 bed extentions. Norwood Edgemate edger. Gehl 4835SXT

Ed

Quote from: Jason_WI on March 17, 2008, 11:04:18 AM
50:1 is too lean for that saw. We mix 40:1 no matter what the manual says. We don't live in California!



The saw will run fine on 50:1 mix. Thats what it was designed for. There are countless numbers of saws that run on that mix every day.

Lurcherman, it sounds to me like you have an air leak, possibly a bad crank seal.

Ed

Jason_WI

QuoteThe saw will run fine on 50:1 mix. Thats what it was designed for. There are countless numbers of saws that run on that mix every day.
Or used to run......... better with too much than not enough.

To find a crank seal leak start up the saw and spray a little ether near the clutch housing. If the saw speeds up then you have a bad seal.

Jason
Norwood LM2000, 20HP Honda, 3 bed extentions. Norwood Edgemate edger. Gehl 4835SXT

SwingOak

One of my coworkers is 2-cycle guru. He has a complete machine shop in his garage and builds trials bikes & motors from the ground up.

He said you'll typically get the most horsepower at 18:1, but the more oil you add, the leaner the mixture gets, and the hotter it will run. He also said something about drilling/porting the piston skirt on the exhaust port side, something about increasing lubrication and lowering operating temperatures. I'm hoping to get a more thorough explanation when he comes into work tonight.

I ordered the parts from Baileys last night too. At $100 or so for a cylinder and piston kit, I'm OK with tinkering a little. Apparently parts for this saw are readily available, so how much damage can I do, really?  ;D

Ed

Quote from: Lurcherman on March 17, 2008, 01:25:51 PM

I ordered the parts from Baileys last night too. At $100 or so for a cylinder and piston kit, I'm OK with tinkering a little. Apparently parts for this saw are readily available, so how much damage can I do, really?  ;D

About $100 bucks worth........
Make sure find the cause of the problem first, otherwise you could junk the new parts the first time it's started after the rebuild.

Ed

SwingOak

So here's the scoop - the exhaust port side of the piston is much hotter than the intake side - by 100-200 degrees or so. By drilling a few small holes through the piston skirt just underneath the rings on the exhaust port side, it allows a tiny bit of the mixture underneath the piston to vent out at the exhaust port. This provides additional lubrication and cooling.

Interesting, isn't it? Apparently this trick is fairly common with motorcycles.

Here's what my suspicions are at the moment - I think the saw is running too hot, maybe too lean from the ethanol in the gas (10%), and is running at too high a maximum RPM. Whatever the case is, I know the saw is running too hot. Maybe also the carb is slightly fouled, causing the mix to run too lean which again will cause it to run hot. When it gets too hot, everything swells up like a tick and parts start interfering that should be just missing each other.

All only conjecture at this point, but I guess I'll find out when I tear it down in the next day or so.


mike_van

50:1 - I know theres a halfazillion people running it, but everytime I read about a siezed up, blown up or burned up saw, it had 50:1 in it.  Just my opinion, but I believe you're "seconds from disaster" with it. If you spit in a half cup of coffee, is that 50:1? Probably pretty close - Not very much oil for something thats cranking 12,000 rpm.  I run all my stuff at 32:1, I've never had to do engine work on any saw I've owned - I bought a 028 in the early 80's, I don't know how many chains I sharpened away on it. The case around the bar stud cracked awhile ago, I tore it down & sold it for parts. There was some carbon on the top of the piston, but the skirts & bore had no scoring at all after 25+ years. I buy the cheapest gas [thats a joke - huh] I can, use whatever 2 cycle oils on sale. I may be some rpm slower, take a second longer to make a cut, but I'm not on the phone buying parts.  Sorry for the rant, just had to say all that.
I was the smartest 16 year old I ever knew.

olyman

also, another unknown tip.......DONT run 50:1 with ethanol gas---alcohol is DRY---and the 50:1 makes it worse. ive run 35:1 in all my saws, with ethanol, since the day ethanol came out. and the saws are still running fine 30 yrs later!!! at 50:1--thats right on the edge, and as others have said--a bit more oil dont hurt------

SwingOak

My parts are due to arrive tomorrow.

Thanks for all the tips on the mix ratio, I do the same with a little 8hp Yamaha outboard I have that calls for 100:1.

I run it at 50:1, because I don't use it much and the advice was from the local boat shop that while it might run fine at 100:1, there just isn't enough oil in the mix to coat internal parts to prevent corrosion or other damage during storage. I don't use my saw in a lake, but it seems the same reasoning could be applied to all two strokes.

And what's more, no matter what my thought process at the time, I shouldn't have tried to force a cut with a dull chain. Duh. That was stupid times 3.  smiley_embarrased


Dale Hatfield

Check carb boot it may have a rip in it.  Also make sure that at whatever mix you run that its not boat mix oil. Ya saw wont last long with it in the tank.
Game Of Logging trainer,  College instructor of logging/Tree Care
Chainsaw Carver

SwingOak

Quote from: Dale Hatfield on March 20, 2008, 12:42:02 AM
Check carb boot it may have a rip in it.  Also make sure that at whatever mix you run that its not boat mix oil. Ya saw wont last long with it in the tank.

Thanks for the suggestion - I checked the carb boot, it's in good shape.

Yeah, I do know about that one & I've always been very careful to keep my marine gas and saw gas separate. Both types say I shouldn't use one type of oil for the other application, and I'm not sure why that is, but there must be a reason. So I don't mix my mix.

Anyway, my most recent checkup on my parts (which did not show up today) shows they might be here Saturday. Nuts.

barbender

I'm also of the opinion that 50:1 is way too lean for chainsaws. I always mix mine at 40:1 with premium non-ethanol gas. This was after I had one saw throw crank bearings and another lock up. The one that siezed had other issues, but the saw that lost the crank bearings had always been a great runner and hadn't seen much use, in fact it was just out of warranty. The mechanic in the saw shop (who has been there probably 20 plus years) told me that he never used to see that before they went to 50:1. People have told me if you mix richer you're saw will carbon up- I say bull- unless you leave it idling all day. When my saws are running they are workin. Dirt bikes that are liquid cooled are mixed at 24:1, I can't see why an air cooled chainsaw should get half that much oil. Okay, my rant is complete as well :)
Too many irons in the fire

Dale Hatfield

I think that Outboards are water cooled pulled up from lower unit. Dont Know for sure thinking and knowing  2 diff things

Dale
Game Of Logging trainer,  College instructor of logging/Tree Care
Chainsaw Carver

SwingOak

Quote from: Dale Hatfield on March 21, 2008, 10:22:19 AM
I think that Outboards are water cooled pulled up from lower unit. Dont Know for sure thinking and knowing  2 diff things

Dale

Yup, they are water cooled. The water intake is below the cavitation plate on the lower unit.

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