Husky 261, mid cut saw dies. Won't start

[domokdow]

I originally posted this in the mills forum where I was given some great info and directed to post here. Below in quotes is my original post. Saltas and Buzz Sawyer advised me to check the flywheel key which may have sheared throwing off my timing. So I tore it down today to look at the flywheel. Problem was I couldn't get the flywheel pulled. Had the puller torqued but, not having a manual, was unsure if I was doing it right when I noticed the puller gouging into the case and flywheel. I had it plenty tight and didn't want to break the flywheel. I figured it should have come off already if indeed a puller was the way to do it. Turns out it is the way but it not coming without a fight. Buzz suggested I look at the piston via the muffler, which I did. There is a decent amount of vertical banding on the piston and a small part of the ring looks deformed. It's hard to see in the pics but it's on the left side of the piston as seen through the exhaust port. I hooked up a compression gauge to see what I could see. With the piston at the bottom of the stroke I gave it one pull. The piston made 4.5 revs with a reading of 49psi. I'm thinking that is low but I'm not sure. Does anybody have any advice or ideas about 1) getting the flywheel off, 2) what should my compression be roughly and finally, is my piston/ring shot. The cylinder wall looks ok from what I can see. Any information would be much appreciated. Can't seem to upload pics, invalid file type error.

"I'm having trouble getting my saw restarted. I stalled it trying to cut too fast through a round and it now will not start. Doesn't even sound like it wants to start. Am getting fuel and am getting spark. Cleaned plug as well.(new) I choke the saw and proceed to crank it. I crank until I smell gas and upon pulling plug I find it wet with fuel. Before this happened the saw ran great and started after 10 or so pulls. Does anybody have any ideas what the problem could be? The fact it doesn't even remotely want to start, meaning no ignition of fuel at all as far as I can tell, seems strange. Any info would be appreciated. Thank you very much."

 

[roostersgt]

Compression should be at least 125+ psi from everything I've ever read. Won't fire no matter what with only 49 psi. Somethings wrong. Probably rings / piston.

 

[nmurph]

If you are choking a hot saw you are probably flooding it. If it is taking 10 pulls on a cold saw with the choke set, you may need to turn the L screw counter-clockwise a little.
What kind of puller are you using? Are you bumping the center bolt a little? Are you holding the saw by the puller when you bump it? I have had FW that wouldn't budge if the saw was laying on bench. If I pick the saw up a couple of inches and then rap on the bolt, they will usually pop right off.
To test compression you should pull until it doesn't climb any further. Also, having the correct type of tester with a relatively short hose and the shrader valve at the point where it screws into the cylinder is critical. That said, 50psi with on pull sounds like you may be ok.

I just read where you said you have vertical stripes. That sounds like a lean seize problem. Don't do anything until you post some pics. We can go from there. Your next step may be to pull the cylinder and have a looksey. We can help you along if you have problems. I have three of these saws (262's) and can pretty much open them up my sleep.

 

[domokdow]

Thanks for the replies Rooster and murph. First, regarding compression, the highest reading I could get was 59 psi with multiple pulls. I'm using a screw in type comp. gauge with one way valve. The puller I'm using is a two arm model I bought for the car pulleys. I do get a fairly good grip.
Rooster, initial start is the only time I choke. I haven't tried bump/pull method but I will if need be. I'm leaning toward piston damage as being the culprit. Looking at the pics would you agree? Thanks again.

 

[Rustynutz]

Don't look good in there! my guess is it's time to look for a new jug and piston etc etc, about $120 £80 "ish"
my experience of flywheel probs if its u/s it would fall off, the fact that it's locked on there! probably mean's it's fine
if the muffler and gasket are in good condition then as stated probably a lean seize so make sure you set that right when you get the new bits fitted (get the recommended RPM and don't go over that!) best of luck.

 

[redunshee]

Don't look good in there! my guess is it's time to look for a new jug and piston etc etc, about $120 £80 "ish"
my experience of flywheel probs if its u/s it would fall off, the fact that it's locked on there! probably mean's it's fine
if the muffler and gasket are in good condition then as stated probably a lean seize so make sure you set that right when you get the new bits fitted (get the recommended RPM and don't go over that!) best of luck.

Agree. Comp should be at least 140 psi or more. Before running saw with new parts be sure that crankseals are good. Something caused your problem and I'd bet it was an air leak.

 

[David (saltas)]

Hello again

I agree with the guys in this thread those pics don't look good and with no compression it won't start.

The flywheel was a possible explanation, based on what you knew and posted at the time, but you have now given further information to diagnose the problem.

Open it up and find out how bad it is. If it has only lightly seized you can remove the alloy stuck to the bore with Hydrochloric acid (muriatic acid or spirits of salt) and a ball of cotton wool, acid resistant gloves too. If you are lucky you may only need rings.

I think you need this style of puller if you want to still check out the flywheel key way. At this point in time I would not bother

http://www.barrettsmallengine.com/partslist/husqvarna261epa-1999-06.PDF

http://www.barrettsmallengine.com/partslist/husqvarna261epa-1998-03.PDF

If you dont have a workshop manual ask for one in the "ask for manual thread"

 

[David (saltas)]

Agree that an air leak is posible

this means extra air is getting in and made it lean

causes crankcase seal next to the crank bearings is common but there are many.

Start reading posts on leak testing the crankcase to find the leak or follow the workshop manual

Don't leave this step out or you risk taosting it again :msp_ohmy:

 

[Cantdog]

Yep your piston is toast...you may well be able to save the cyl with the acid treatment. Hard to tell at this point. You will definately need a new piston and I would replace both crank seals while you at it and have the whole thing apart and eliminate the possibilities of an air leak there. As has already been said you need to find the cause of the damage not just fix whats ruined or it will most surely happen again to your new parts. Good luck...those are nice saws...

 

[nmurph]

Yes, the piston is toasted. As mentioned, pull the cylinder and let us see some pics. Most cylinders will clean up with muriatic acid.
I would definitely replace the dished 261 piston with a flat 262 piston. Meteor is the brand I would prefer. Baileys and Northwoods Saw both carry them. They are equivalent to OEM.

 

[Cantdog]

Yes, the piston is toasted. As mentioned, pull the cylinder and let us see some pics. Most cylinders will clean up with muriatic acid.
I would definitely replace the dished 261 piston with a flat 262 piston. Meteor is the brand I would prefer. Baileys and Northwoods Saw both carry them. They are equivalent to OEM.

Yep...what he said....

 

[domokdow]

Thank you very much guys for all the input. Rustynutz, redunshee and cantdog: I'm going to get a piston and crank seals ordered this weekend and I will pull the cylinder as well. The muffler and gasket are in good condition.
nmurph, thanks for the recommendations. I will check them out. I will get a flat head piston if it's not too much more expensive. I assume a flat piston will generate more power compared to a dished head? I suppose removing the screen from the exit hole of the muffler would help too. I will post pics of the pulled parts as soon as.
Thanks saltas for your time. My story did change upon a closer look. I hate when that happens. I do have some muratic acid. I have some sulfuric as well but probably shouldn't go there. I'm keeping my fingers crossed and hoping I don't need a new cyl.
Thanks again all.

 

[masculator]

looks like you cooked that piston good and proper. pull the top off and you will see just how bad. the cylinder may be salvageable but the piston is beyond it by what I can see from your pics. Now you need to know what caused it so it doesn't happen again!

 

[masculator]

Thank you very much guys for all the input. Rustynutz, redunshee and cantdog: I'm going to get a piston and crank seals ordered this weekend and I will pull the cylinder as well. The muffler and gasket are in good condition.
nmurph, thanks for the recommendations. I will check them out. I will get a flat head piston if it's not too much more expensive. I assume a flat piston will generate more power compared to a dished head? I suppose removing the screen from the exit hole of the muffler would help too. I will post pics of the pulled parts as soon as.
Thanks saltas for your time. My story did change upon a closer look. I hate when that happens. I do have some muratic acid. I have some sulfuric as well but probably shouldn't go there. I'm keeping my fingers crossed and hoping I don't need a new cyl.
Thanks again all.

There are better things you can do than remove the spark arestor screen and if you cut any where that rangers roam you need that screen in place.

 

[Cantdog]

Thank you very much guys for all the input. Rustynutz, redunshee and cantdog: I'm going to get a piston and crank seals ordered this weekend and I will pull the cylinder as well. The muffler and gasket are in good condition.
nmurph, thanks for the recommendations. I will check them out. I will get a flat head piston if it's not too much more expensive. I assume a flat piston will generate more power compared to a dished head? I suppose removing the screen from the exit hole of the muffler would help too. I will post pics of the pulled parts as soon as.
Thanks saltas for your time. My story did change upon a closer look. I hate when that happens. I do have some muratic acid. I have some sulfuric as well but probably shouldn't go there. I'm keeping my fingers crossed and hoping I don't need a new cyl.
Thanks again all.

Northwoods Saw (site sponsor top of page) has the 262XP pistons (Meteor flat top) for $31.95 and they are great to do business with and ship very quickly and inexpensively....that said I would advise against using their seals...I was not impressed with the ones I got from them. I am sure they would have made it right but it was such a small number of seals I didn't whine about it. I would either go to a bearing supply place (take an old seal with you) or a husky dealer for the seals. I doubt you could even find an aftermarket dished (261) piston for this saw...everyone always goes for the 262 flat top.

You will have to be patient with the acid...it isn't instant and requires some elbow grease. I usually apply with a q-tip and let set 10-15 minutes then flush with water and rub with scotchbright and/or 400 wetndry repeat as needed. Don't get discouraged...It may an hour or more to get it cleaned up. Good luck...

 

[ncfarmboy]

Northwoods Saw (site sponsor top of page) has the 262XP pistons (Meteor flat top) for $31.95 and they are great to do business with and ship very quickly and inexpensively....that said I would advise against using their seals...I was not impressed with the ones I got from them. I am sure they would have made it right but it was such a small number of seals I didn't whine about it. I would either go to a bearing supply place (take an old seal with you) or a husky dealer for the seals. I doubt you could even find an aftermarket dished (261) piston for this saw...everyone always goes for the 262 flat top.:

That's funny I just bought a box of cylinders and a couple of pistons. Low & behold there is a NOS OEM 261 piston in the group. guess I'll use it for a paper weight. I've been throwing good used 261 pistons in the scrap cause I change em all to a Meteor 262.
Shep