Interesting on the filter problems you say you experiance. I have never run into that at all with my 2500 or my buddies 295 which are from that familey.
In fact I don't think the buddy ever cleans it till I get to it.
Nik's Poulan Thread
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Interesting on the filter problems you say you experiance. I have never run into that at all with my 2500 or my buddies 295 which are from that familey.
In fact I don't think the buddy ever cleans it till I get to it.
rms61moparman
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According to an old small engine mechanic, friend of mine, the aluminum cylinders go through some sort of burnishing process that hardens them.
He is the one who told me to NEVER bore or even hone an aluminum cylinder because if you ever break through the hardened part you have a very expensive piece of aluminum CRAP left.
This buddy of mine knew a guy who had a machine to reharden the aluminum, but my friend drank himself to death before he ever took me to meet the other man.
Mike
He is the one who told me to NEVER bore or even hone an aluminum cylinder because if you ever break through the hardened part you have a very expensive piece of aluminum CRAP left.
This buddy of mine knew a guy who had a machine to reharden the aluminum, but my friend drank himself to death before he ever took me to meet the other man.
Mike
It has been a long time but I think the process that Chevy used was an acid bath to remove the aluminum and leave the silicone.
There were other processes that used electrical discharge to vaporize hard metal and plate it to the aluminum cylinders. This was written up in some of the motorcycle magazines I used to subscribe to.opcorn:
If I'm not mistaken, GM in later Vega models used sleeves in their engines.
moparman
ArboristSite Member
unplated cylinders
The unplated Poulan cylinders are made with 390 aluminum which has a high percentage of silicon particles in it. The cylinder must be bored correctly so that the particles are not fractured & to ensure that the exposed silicon particles are not smeared over with aluminum. The silicon particles are hard enough to support the piston rings. The piston must be plated correctly with either chrome or nickel. Dis-similar materials must be ran on piston & cylinder or they will seize. Chrome was intially used on pistons by Poulan and other manufacturers with bare bore cylinders, however nickel boron plated pistons work much better - this is what most plated pistons use now. This combination works very well, except in a very few locations where there is a large amount of very fine abrasive dust.
The problem with muffler bolts coming out occurs on older saws with long mounting bolts which have been allowed to loosen. When they loosen and the loose muffler is continued to be ran, the bolt threads vibrate and wear the cylinder aluminum and it is then very hard to keep the bolts tight. The worst thing that you could do is remove the guts from the muffler. The reason that the bolts loosen is that they and muffler expand from the heat of exhaust and try to pull the aluminum threads out. When the engine cools, the bolts have been stretched a little and therefore loose some on the clamp force retaining the muffler. This allows the bolt to start backing off or sometimes break. This is a problem with any saw that has long muffler bolts. This is the reason that most newer saws now have very short muffler bolts contained in tubes in the muffler.
The unplated Poulan cylinders are made with 390 aluminum which has a high percentage of silicon particles in it. The cylinder must be bored correctly so that the particles are not fractured & to ensure that the exposed silicon particles are not smeared over with aluminum. The silicon particles are hard enough to support the piston rings. The piston must be plated correctly with either chrome or nickel. Dis-similar materials must be ran on piston & cylinder or they will seize. Chrome was intially used on pistons by Poulan and other manufacturers with bare bore cylinders, however nickel boron plated pistons work much better - this is what most plated pistons use now. This combination works very well, except in a very few locations where there is a large amount of very fine abrasive dust.
The problem with muffler bolts coming out occurs on older saws with long mounting bolts which have been allowed to loosen. When they loosen and the loose muffler is continued to be ran, the bolt threads vibrate and wear the cylinder aluminum and it is then very hard to keep the bolts tight. The worst thing that you could do is remove the guts from the muffler. The reason that the bolts loosen is that they and muffler expand from the heat of exhaust and try to pull the aluminum threads out. When the engine cools, the bolts have been stretched a little and therefore loose some on the clamp force retaining the muffler. This allows the bolt to start backing off or sometimes break. This is a problem with any saw that has long muffler bolts. This is the reason that most newer saws now have very short muffler bolts contained in tubes in the muffler.
Yup same stuff the Vega's were made out of...
This explains the aluminum bore, plated piston thingy.
Regardless of what they did with that junky 4 cylinder, I like the Vegas the way they are today...with small block Chevy V8s in them!
Mark, my former neighbors Tim Allen signature Bad Boy saw did have a unplated cylinder . Maybe it wasn't a factory cylinder, I didn't ask him about the saw history. I didn't know that the 3450 had the different pistons and cylinders.
redunshee
Addicted to ArboristSite
Poulan 245A starting issues
Saw ran but quit after 15 minutes. I figured it was either coil or carb. Rebuilt carb but still will not start. I can smell fuel so I figure it is getting gas.
Question 1: I assume metering diaphragm notch fits in metering needle and doesn't sit on top like other carbs.
Question 2: Getting spark but wonder if coil not delivering enough spark to fire saw? I cleaned and reset points and condenser seems okay. All wiring looks okay. Spark isn't blue which is why I'm questioning spark.
I'm getting another 245 parts saw and may as a last resort switch coil and/or carb and see what happens. However I thought I'd pick the brains of the experts. Thanks
Bob
Saw ran but quit after 15 minutes. I figured it was either coil or carb. Rebuilt carb but still will not start. I can smell fuel so I figure it is getting gas.
Question 1: I assume metering diaphragm notch fits in metering needle and doesn't sit on top like other carbs.
Question 2: Getting spark but wonder if coil not delivering enough spark to fire saw? I cleaned and reset points and condenser seems okay. All wiring looks okay. Spark isn't blue which is why I'm questioning spark.
I'm getting another 245 parts saw and may as a last resort switch coil and/or carb and see what happens. However I thought I'd pick the brains of the experts. Thanks
Bob
Not an expert, but I got my 245 going. Notch on yours is correct. Did you check height of lever? I imagine some people bend them up a little so they can put diaphragm in notch easier, probably not a good thing to do. Spark should be kinda blue and the more spark the better. You might check your coil to flywheel clearance. Should be about 10 thousandths.
lawnmowertech37
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i would change out the pts and condenser see what that does
Bob, the Chain Saw Service Manual specs the point gap on your 245A to be 0.017",and the magneto air gap is 0.012" .
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rinkrat311
ArboristSite Lurker
any of the poulan pro's out there know if i can swap an older 295 7 tooth .325 sprocket onto my 4218? just looking for options for B&C and it seems there are more out there for my saw in the .325 pitch than in the 3/8.
thanks:greenchainsaw:
thanks:greenchainsaw:
redunshee
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Do you have parts, Calvin?
redunshee
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Thanks, Scott. Will recheck. I did set points at .017 and used a business card for the air gap. Maybe points moved or it is bad.
redunshee
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My guess is spark is marginal which leads me to coil, points or condenser. However try and find them.
I'd bet that your condenser is leaky (bad).
redunshee
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Could be though I went to my Stihl dealer and it checked out okay. Saved me from buying one. Maybe I should have bought one anayway. Did check points and here is my question: Does the round felt pad sit on the points plate? If it does I can't get points to close anywhere near .017. More like .030. If it stays on top of the points on the crank shaft, what is its purpose?
I think they meant for you to put a drop of oil on the pad to keep the rubbing block on the points lubricated. I usually slip just a bit of grease on the side of the rubbing block though. The felt pad rubs against the cam for the points and keeps the block lubricated. I think the next thing I'd suspect would be the coil. The way you described it is the way some coils go out..when they get warmed up they open up, when they cool back off they go back together.
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Yeah, right. Who's making non factory cyls for 3750's? LOL.
No Scott, I believe your mistaken till I find documents telling me otherwise.
All my documents also match whats on the Poulan website as well.
No, not as far as I can see that 295 sprocket fitting. That 4218 is a differnt series of saws, then the 295/4620 saws.
The 4218 is more along the Wildthing family.
Bob, I have had trouble with those round felts as well, they seem to swell up with age and interfear with the points. I just throw them away! As long as the cork gasket around the case is good, its not really needed anyway.
Sounds like you are haveing points trouble, I rarely see coils go bad but it could happen.
Do you own a spark tester? If not you should as you need to make sure the spark will jump the gap on a good spark tester. I have seen them jump a plug gap and not the tester.
If they wont jump the tester, most the time they wont run.
If you can't get it right, instead of spending money on new points and condensor, you may want to try a Nova module. I worked on a guys 245 a while back with one on it and it worked great.
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