Nik's Poulan Thread

[zogger]

Hey Mark, thats not just any ol aluminum its alumasil , even my old 1980 and 1981 B&S 3HP Classics are still goin strong thanks to Castrol 30wt.

Ya, this alusil. first I ever heard of it. Seems to work quite well! The wikki article has a buncha high end cars using it, wonder why more saw companies don't use it?

 

[stubnail67]

cool!

I bought the small HF one. Ive done 3 carbs so far. Very happy with the results. I plan on buying one of the bigger better units Ive seen on ebay but I wanted to try the small cheap one first. The only problem with the small HF one is a very short cycle time (maybe 3 minutes), I cycle it 7 or 8 times. The tank on mine is stainless with a removable parts basket and light. I use a cup of hot water and some simple green. When Its done I give them a quick shot of carb cleaner then dry them over night on paper towels. I did it to my 2.3 micro, 3700 and 335. All run very well.

thats what i was hopin i will also look around on CL local and see if i can find an old dentle one if not HF here i come...

 

[rms61moparman]

I thought if there was chips or flakes gone from above the exhaust port it was no good, trash it? That's the status of my echo cylinder and at over 150 for a cylinder and close to 60 for a piston set, it's staying in that condition.

I cleaned it once, with the acid and sandpaper, that's how I found the missing plating, started bubbling bad. I quick rinsed it off with water. Then went to just sanding. Put in a new ring after also sanding smooth (kinda sorta) the piston and it ran for like two cuts then quit again. Fast disassembly to take a look, back to smeared galled cylinder. It sits like that now.

I wonder now if just a totally new piston and reclean the cylinder might work. A piston I can swing now, the whole deal, nope, need that freezer, proly a used one.
But..it has some lost plating for sure. I'd hate to trash a 60 buck piston on that, or have chips of stuff get down into the crankcase.

Has there ever been ANY successful attempts to patch small areas of lost plating, with any super duper like space program certified type epoxy anything? I know you can have a cylinder honed out and replated, etc, that's only for antiques or like expensive cycles etc. not worth it on a relatively cheap common saw, cost more than a new one anyway.

I just can't help but think there must be some sort of advanced chemistry out there with a metallic embedded epoxy, for real small cylinder patches. I went looking awhile back, best I found was oil and gas resistant, 1,000 F temp resistant, some shock resistant stuff. 40 bucks for a real small amount. Has to be heat cured in an oven.

Oh, found this easily enough

Alusil - Wikipedia, the free encyclopedia

That explains how the 3400s and cousins can work. If it was all through the casting, the whole cylinder, you'd only need a slight honing or good bore job and oversize rings for a rebuild! Must be expensive and about like nikasil plating. thin, real dang thin.

It just all depends on where it is, how big of an area it covers, how it is shaped etc.


Mike

 

[Showme]

Seems you think you know me. I would gladly let you pick me up on the way down there and I would gladly let a couple of my bigger saws ride in your car. In the back seat leaking oil all over it.


(just kidding)



Dont know what its supposed to be for free revs. Not sure I ever seen a listing for it. Put the tach away, tune it by ear WOT then tune it again in the wood. If you really want to know what the WOT RPM should be, you can then tach it.

Yep, that's what I'm doing just wondered since I'm not that familiar with older saws if I was about right or not. Sounded right, cleaned up in the wood. Big difference in running a screaming 562XP and turning around and running a 375 or SXL. I'm trying to educate my ears.

 

[nick 55]

thats what i was hopin i will also look around on CL local and see if i can find an old dentle one if not HF here i come...

I have the large HF one. If that's the route you go, make SURE you dig through the local Sunday paper or the car magazines and find an HF ad where they have a 20% off coupon. If you can't find one, PM me and I'll send you one as I can't buy enough tools for the coupons I get in all my car mags. Also, don't use Purple Power on carbs as it reacts with the metals and makes the pieces fizz like Alka-Seltzer and turn dark grey.

Nick

 

[redunshee]

Single Ring????

I'll re-post of sorts. Anyone experimented with only running the top ring on a two ring saw? Wonder if there would be a perf. improvements as many large saws only use one ring. Better question " are there any drawbacks?"

Bob

 

[chainsawwhisperer]

I'll re-post of sorts. Anyone experimented with only running the top ring on a two ring saw? Wonder if there would be a perf. improvements as many large saws only use one ring. Better question " are there any drawbacks?"

Bob

There was a thread on this a long time ago. Couple guys mentioned that they do it all the time with no draw backs.
Sorry, I don't remember any more than that.
jim

 

[OhioGregg]

I'll re-post of sorts. Anyone experimented with only running the top ring on a two ring saw? Wonder if there would be a perf. improvements as many large saws only use one ring. Better question " are there any drawbacks?"

Bob

Bob, I can't help ya with any technical knowledge, thats for sure. I guess there is only one way to find out for sure, and thats do it. LOL I just never liked being the guinea pig. Back when I was messing around with RC airplanes, one of the popular small gas engines that people liked to convert to RC use, was the Ryobi 31cc engine. The early ones had one ring, the later ones had 2 rings. Everybody swore the two ring model made more power, and was the one to use. Along with a carb with a slightly larger venturi. I tried both, and wouldn't swear on a stack of bibles that the two ring was stronger. I think it was. But then I went into it thinking it was going to be stronger to start with.

I think I would just stick with the two rings on the saw your working on. It was designed by smarter guys than me that way. I can't imagine leaving one ring off of it will do it any good. But do let us know how it works out.


Gregg,

 

[redunshee]

Bob, I can't help ya with any technical knowledge, thats for sure. I guess there is only one way to find out for sure, and thats do it. LOL I just never liked being the guinea pig. Back when I was messing around with RC airplanes, one of the popular small gas engines that people liked to convert to RC use, was the Ryobi 31cc engine. The early ones had one ring, the later ones had 2 rings. Everybody swore the two ring model made more power, and was the one to use. Along with a carb with a slightly larger venturi. I tried both, and wouldn't swear on a stack of bibles that the two ring was stronger. I think it was. But then I went into it thinking it was going to be stronger to start with.

I think I would just stick with the two rings on the saw your working on. It was designed by smarter guys than me that way. I can't imagine leaving one ring off of it will do it any good. But do let us know how it works out.


Gregg,

Yea Gregg, I'm not an experimenter either. I saw an old Thread where SawTroll said that two rings only adds friction. Yet, the P+C were designed for two rings. Guess I'll go with what is recommended. Thanks.
Bob

 

[OhioGregg]

Yea Gregg, I'm not an experimenter either. I saw an old Thread where SawTroll said that two rings only adds friction. Yet, the P+C were designed for two rings. Guess I'll go with what is recommended. Thanks.
Bob

Bob, I think SawTroll was probably concerned that it added 0.235 ounces of weight to the saw.


Gregg,

 

[zogger]

Bob, I can't help ya with any technical knowledge, thats for sure. I guess there is only one way to find out for sure, and thats do it. LOL I just never liked being the guinea pig. Back when I was messing around with RC airplanes, one of the popular small gas engines that people liked to convert to RC use, was the Ryobi 31cc engine. The early ones had one ring, the later ones had 2 rings. Everybody swore the two ring model made more power, and was the one to use. Along with a carb with a slightly larger venturi. I tried both, and wouldn't swear on a stack of bibles that the two ring was stronger. I think it was. But then I went into it thinking it was going to be stronger to start with.

I think I would just stick with the two rings on the saw your working on. It was designed by smarter guys than me that way. I can't imagine leaving one ring off of it will do it any good. But do let us know how it works out.


Gregg,

I've seen it mentioned several times on the saw forum that some guys leave out one ring. OK, with that said, I am of the opinion that two rings help establish and center the piston in the cylinder better and keep it from excessive rocking.

 

[nick 55]

Bob, I think SawTroll was probably concerned that it added 0.235 ounces of weight to the saw.


Gregg,

Yeah, he didn't want his 74cc saw being tail heavy after he found a 16" lightweight bar for it.

Nick

 

[Chris J.]

Bob, I think SawTroll was probably concerned that it added 0.235 ounces of weight to the saw.


Gregg,

LMAO!
I can't rep you, need to spread it around.

 

[Eccentric]

LMAO!
I can't rep you, need to spread it around.

Got him for you Chris!

 

[edisto]

I've seen it mentioned several times on the saw forum that some guys leave out one ring. OK, with that said, I am of the opinion that two rings help establish and center the piston in the cylinder better and keep it from excessive rocking.

They would need to be spaced pretty far apart to make a difference in that regard, and there has to be wiggle room behind the ring, because it is the gas pressure behind the ring that makes the ring seal.

One critical, and often overlooked, function of the rings is to transfer heat from the piston to the cylinder. I wouldn't imagine you lose half of that ability by dropping a ring, but you do lose some fraction.

That can be important from a power standpoint because less efficient heat transfer through the rings allows heat transfer to the charge, which expands the volume, allowing less fuel into the cylinder on the next go-round.

 

[edisto]

Got him for you Chris!

I got him for me!

 

[zogger]

They would need to be spaced pretty far apart to make a difference in that regard, and there has to be wiggle room behind the ring, because it is the gas pressure behind the ring that makes the ring seal.

One critical, and often overlooked, function of the rings is to transfer heat from the piston to the cylinder. I wouldn't imagine you lose half of that ability by dropping a ring, but you do lose some fraction.

That can be important from a power standpoint because less efficient heat transfer through the rings allows heat transfer to the charge, which expands the volume, allowing less fuel into the cylinder on the next go-round.

How many high end modern pro saws are using a single ring? Most or all of them? I really don't know, my edumakation and experience with any modern type pro class saws, of any size made... is...zero.

 

[rms61moparman]

How many high end modern pro saws are using a single ring? Most or all of them? I really don't know, my edumakation and experience with any modern type pro class saws, of any size made... is...zero.

I never counted it up but there are PLENTY of them, and wothout question, some of the best runners!!!


Mike

 

[edisto]

I'm not saying you can tell anything about saw quality by counting rings, I'm just saying why I wouldn't pull a ring off of a piston that had room for 2.

 

[Moparpoulan]

655bp

So as of today I have a 655bp in the mail:hmm3grin2orange:, the only problem is the previous owner has told me that the saw sat for a long time and when he put bar oil in it leaked into the fuel tank. I took a look at the IPL on the ordertree website and the gasket between the case is still available and in stock. Has anyone ever done one of these? Im expecting to have to do fuel lines and a carb kit also based on it sitting for so long, but I paid the right price for it so Im not too worried. Ill try and post some pictures up as soon as it arrives.