Nik's Poulan Thread

[Eccentric]

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.

That gasket goes between the case halves. Doesn't seperate the oil and fuel. There's a glued-in divider between the two tanks. That gasket will come in handy if you split the case to repair the tank divider however. This is a common problem with the PP655 and the earlier saws in the family. Some guys have fixed it without splitting the cases. Others have gone whole hog and split the cases to deal with it......

 

[cbfarmall]

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.

I have tried and failed 3 times to reseal this divider without splitting the saw. It'll last for a while, but one day you'll find fuel in the oil tank. Bottom line, you cannot get it clean enough due to limited access thru the fuel/oil caps. I have all the gaskets and a genuine BP topend for mine. Just waiting find the motivation.

Chris B.

 

[Modifiedmark]

I have not split a 655 but I plan on doing it with Chris soon on his as the divider in it fell out again. It was repaired last time working through the tank fill hole and thats just a damn hard way to do it and get it right.

I look forward to overseeing him do it just to see whats in them. I have a Poulan service bulletin about that divider somewhere and it said the case needs to be split to do it. I'll see if I can find that bulletin.

 

[Modifiedmark]

Found it!

Dang Chis we posted at the same time!!!!

 

[crowellmachine]

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


Mike

FWIW, In the 2 stroke sled world, Most high performance applications use a single "L" ring right at the tippy top of the piston. From what I have learned, read, and studied, This is a 2 fold benefit......

1) The top lip of the ring being exposed to the explosion creates an excellent ring seal, because of the force pushing down the crown of the piston, and shoving against the lip sticking up......

2) Minimal friction, heat and drag are less than a 2 ring setup.

The bad.... it is extremley easy to burn the ring, and lose the temper (springy-ness) of it. "piston slap" occurs prematurely. (personal experience ) I see no advantage to using only 1 ring on a piston designed for 2.

My .02 KJC

 

[crowellmachine]

Fuel tank fittings

To Mark mostly, and others also:

The lathe work is done on these, I took some video. I can't mill the hex this week, Mill dept. is booked solid until mid next week. I will post a
youtube video after they are complete. made 50 of them. ......They're pretty shiny......

Bought a new "forklift" today, Its 70hp, orange, 4wd cab,air,heat......3pt hitch. M7040, hydraulic shuttle, like this one..........

Kubota M7040 HDC Tractor - YouTube

Having a pretty good day,

KJC:cool2:

 

[zogger]

Alternative mod

That gasket goes between the case halves. Doesn't seperate the oil and fuel. There's a glued-in divider between the two tanks. That gasket will come in handy if you split the case to repair the tank divider however. This is a common problem with the PP655 and the earlier saws in the family. Some guys have fixed it without splitting the cases. Others have gone whole hog and split the cases to deal with it......

Just a thought..instead of redoing the tank divider, go through the junk pile, find two plastic oil/fuel tanks from something else, the approximate size needed, from anything, who cares, old busted trimmer or blower or cheap saw, anything, just mix and match, drop them in that space, and skip the divider. It's a weak link, go higher tech, more modern for the mod.

 

[Modifiedmark]

To Mark mostly, and others also:

The lathe work is done on these, I took some video. I can't mill the hex this week, Mill dept. is booked solid until mid next week. I will post a
youtube video after they are complete. made 50 of them. ......They're pretty shiny......

Bought a new "forklift" today, Its 70hp, orange, 4wd cab,air,heat......3pt hitch. M7040, hydraulic shuttle, like this one..........

Kubota M7040 HDC Tractor - YouTube

Having a pretty good day,

KJC:cool2:

Karl that sounds great on the fittings. Your the man!

As for the forklift, that thing is sweet! Nice, nice, nice...

I was hopeing to get my NH TC-29's loader converted over to a skid steer bucket setup on it and get forks for it for helping with the wood cutting but.... the tax check wasnt that big and I ended up haveing to replace the outside french doors on the kitchen and redo the floor since the other door went bad so I'll have to wait a bit for the forks.

 

[Modifiedmark]

Just a thought..instead of redoing the tank divider, go through the junk pile, find two plastic oil/fuel tanks from something else, the approximate size needed, from anything, who cares, old busted trimmer or blower or cheap saw, anything, just mix and match, drop them in that space, and skip the divider. It's a weak link, go higher tech, more modern for the mod.

Sorry, you dont really understand this do you? :hmm3grin2orange:

 

[zogger]

FWIW, In the 2 stroke sled world, Most high performance applications use a single "L" ring right at the tippy top of the piston. From what I have learned, read, and studied, This is a 2 fold benefit......

1) The top lip of the ring being exposed to the explosion creates an excellent ring seal, because of the force pushing down the crown of the piston, and shoving against the lip sticking up......

2) Minimal friction, heat and drag are less than a 2 ring setup.

The bad.... it is extremley easy to burn the ring, and lose the temper (springy-ness) of it. "piston slap" occurs prematurely. (personal experience ) I see no advantage to using only 1 ring on a piston designed for 2.

My .02 KJC

I was reading the other day not about sleds, but racing two stroke bikes, then the small single ring at the top, I guess similar to what you are talking about. Those things only last for hours! Those guys rebuild the engines all the time. I was reading on some forum, guys talking about being able to squeeze out six hours between rebuilds. Say whut??

I think I'd rather shoot for longevity design over squeezing the last possible eenie little bit of potential horsepower/torque out.

Not into racing much at all. with anything. I like solid, works, works for years, type stuff. As in, I know this site has a hotsaws forum, but I never go there. I can understand the concept of a woodsport, sounds OK, saws now come stock de-tuned to a ridiculous amount, the woodsport and MM gets them back to "normal" good working condition, but much past that....ain't seeing the point much, so I don't have a lot of interest in those extreme designs.

Now modern metallurgical and chemistry advances, sure, like to see that. Ceramic bearings, someday ceramic pistons and cylinders, graphite impregnated alloys, etc. But way over stressed components designed to barely make it to the end of some race...nope.

Different strokes for different folks, pun intended.

 

[edisto]

FWIW, In the 2 stroke sled world, Most high performance applications use a single "L" ring right at the tippy top of the piston. From what I have learned, read, and studied, This is a 2 fold benefit......

1) The top lip of the ring being exposed to the explosion creates an excellent ring seal, because of the force pushing down the crown of the piston, and shoving against the lip sticking up......

2) Minimal friction, heat and drag are less than a 2 ring setup.

The bad.... it is extremley easy to burn the ring, and lose the temper (springy-ness) of it. "piston slap" occurs prematurely. (personal experience ) I see no advantage to using only 1 ring on a piston designed for 2.

It sounds like the situation you describe in 1) is atypical, and called "flutter". Under normal conditions, Dykes rings functions the same as a normal ring, but if flutter does occur, the expanding gas can still act from behind the ring, even though it can't get into the ring groove.

I don't quite follow the "piston slap" problem though...seems like the high placement of a Dykes ring wouldn't prevent that, regardless of radial tension? The outward pressure exerted by the ring itself is pretty minimal to begin with (which is why you need the gas pressure behind it to generate a seal).

 

[zogger]

Sorry, you dont really understand this do you? :hmm3grin2orange:

If you mean a stock restoration over something else, sure I do. Just thought I would throw that alternative out there if it might be useful.

maybe there's something here I shoud clarify about myself. Although I hang out here and am enjoying the old poulans, I am not a collector per se, I just accumulate good deals on quality old used saws, as this is what I can afford, and they are simple to work on and work well when running. I'm not interested into having say a full collection of every variant of a saw/model run/brand/ re baded color, etc. I own an old wheelhorse, I like it. I am not real interested in having a barn full of them, all the variants, all restored, to take to the show a few times a year. I just like having a cheap small tractor that is useful and functional.

I have nothing *against* that at all, the collecting and pristine restoring and etc, just not exactly what I am into.

Now, if you meant something else, nope, I don't get it then. I fully admit to being quite dense sometimes.

 

[Modifiedmark]

If you mean a stock restoration over something else, sure I do. Just thought I would throw that alternative out there if it might be useful.

maybe there's something here I shoud clarify about myself. Although I hang out here and am enjoying the old poulans, I am not a collector per se, I just accumulate good deals on quality old used saws, as this is what I can afford, and they are simple to work on and work well when running. I'm not interested into having say a full collection of every variant of a saw/model run/brand/ re baded color, etc. I own an old wheelhorse, I like it. I am not real interested in having a barn full of them, all the variants, all restored, to take to the show a few times a year. I just like having a cheap small tractor that is useful and functional.

I have nothing *against* that at all, the collecting and pristine restoring and etc, just not exactly what I am into.

Now, if you meant something else, nope, I don't get it then. I fully admit to being quite dense sometimes.

It was the something else. Dont have any idea what you were talking about, but its near impossable to put another tank inside the tank through the fill hole, if that was what you were implying.


Fixing something right dont have anything to do with collecting etc and its not a really expensive fix for a saw that is worth more then a couple bucks...

 

[crowellmachine]

I was reading the other day not about sleds, but racing two stroke bikes, then the small single ring at the top, I guess similar to what you are talking about. Those things only last for hours! Those guys rebuild the engines all the time. I was reading on some forum, guys talking about being able to squeeze out six hours between rebuilds. Say whut??

I think I'd rather shoot for longevity design over squeezing the last possible eenie little bit of potential horsepower/torque out.

Not into racing much at all. with anything. I like solid, works, works for years, type stuff. As in, I know this site has a hotsaws forum, but I never go there. I can understand the concept of a woodsport, sounds OK, saws now come stock de-tuned to a ridiculous amount, the woodsport and MM gets them back to "normal" good working condition, but much past that....ain't seeing the point much, so I don't have a lot of interest in those extreme designs.

Now modern metallurgical and chemistry advances, sure, like to see that. Ceramic bearings, someday ceramic pistons and cylinders, graphite impregnated alloys, etc. But way over stressed components designed to barely make it to the end of some race...nope.

Different strokes for different folks, pun intended.

I would not have agreed with you 10 years ago, But I have learned a bit since then...(leave it alone)..one last note on the topic, I have seen dyno sheets studying the single/dual ring question. The single ring can produce as much as 15 lbs. compression over a dual ring setup. Cold engine, all conditions equal. The dyno sheets comparing the two showed not so much a gain in peak hp; but a boost in midrange torque, using the single ring. The increase was enough to be measured, but only noteworthy in a competitive situation.

KJC

 

[homelitejim]

If you mean a stock restoration over something else, sure I do. Just thought I would throw that alternative out there if it might be useful.

maybe there's something here I shoud clarify about myself. Although I hang out here and am enjoying the old poulans, I am not a collector per se, I just accumulate good deals on quality old used saws, as this is what I can afford, and they are simple to work on and work well when running. I'm not interested into having say a full collection of every variant of a saw/model run/brand/ re baded color, etc. I own an old wheelhorse, I like it. I am not real interested in having a barn full of them, all the variants, all restored, to take to the show a few times a year. I just like having a cheap small tractor that is useful and functional.

I have nothing *against* that at all, the collecting and pristine restoring and etc, just not exactly what I am into.

Now, if you meant something else, nope, I don't get it then. I fully admit to being quite dense sometimes.

I hear what you are saying, I also like a good deal on any saw, it is hard to pass up a Poulan 8500 for $20, let alone 3. The fun for me is getting my POS $20 saw to run and cut wood as it was originally intended, unfortunately having as many saws as I do either makes me a collector or a hoarder and luckily for me people collect chainsaws and guns so I am a collector. Some day I would like to get into the restoration side of collecting.

 

[crowellmachine]

It sounds like the situation you describe in 1) is atypical, and called "flutter". Under normal conditions, Dykes rings functions the same(better than) as a normal ring, but if flutter does occur, the expanding gas can still act from behind the ring, even though it can't get into the ring groove. (why does the expanding gas want to end up in the ring groove?)

I don't quite follow the "piston slap" problem though..(not referenced as a problem).(I meant that as a separate issue, independent of the ring condition)seems like the high placement of a Dykes ring wouldn't prevent that, (the ring losing its springy-ness was related to more critical jet adjustment) regardless of radial tension? The outward pressure exerted by the ring itself is pretty minimal to begin with (which is why you need the gas pressure behind it to generate a seal).

I understand how dyke-style rings work. I was trying to compare the two (L rings vs. Conventional), from a performance standpoint and show the pro's and con's of each. My post was not diagnosing a problem. Piston slap occurs in a shorter period of time with a single ring piston. The reason its a "problem" is, if you let it go too long, your skirts start to break off, and go up the transfers, and grenade the motor.

I think you either didn't read all the posts about discussion, or are mis-interpreting what I've tried to say.
I am experienced enough to understand all of the technical jargon used above, but for the good of the group and the intention of this forum, I feel it is somewhat un-neccessary. It is probably best if we put this topic to bed.

Best regards, Karl

 

[a. palmer jr.]

It was the something else. Dont have any idea what you were talking about, but its near impossable to put another tank inside the tank through the fill hole, if that was what you were implying.


Fixing something right dont have anything to do with collecting etc and its not a really expensive fix for a saw that is worth more then a couple bucks...

I was kinda wondering that too. Maybe take a hacksaw and cut a big window in the saw and slip a couple of weedeater tanks in there...Just kidding...better do what the manual says, can't be much worse than a 330 homie boot replace.

 

[Nardoo]

When we were kids my younger brother tried to build a sailing ship in an old sherry flagon. Spent hours poking little sticks and glue down the neck. He ended up smashing the bottle in frustration and while I always figured it was impossible, I kind of admired his ambition.

Al.

 

[redunshee]

Just a thought..instead of redoing the tank divider, go through the junk pile, find two plastic oil/fuel tanks from something else, the approximate size needed, from anything, who cares, old busted trimmer or blower or cheap saw, anything, just mix and match, drop them in that space, and skip the divider. It's a weak link, go higher tech, more modern for the mod.

You mean after splitting the case.?

 

[nick 55]

I'm pretty sure he did mean after splitting the case. I thought it was a pretty good idea if anyone has had a baffle come loose after a repair. I don't know how durable the "approved" repair is though either(whether the adhesive used is truly fuel proof).

Nick