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Hello gents, I have a friend that is in search of stage 2 Boyesen reeds for a P51. Any chance someone want to part with one? If not, can you please share a part number? Thanks!
 
Hello gents, I have a friend that is in search of stage 2 Boyesen reeds for a P51. Any chance someone want to part with one? If not, can you please share a part number? Thanks!

If you call Boysen, they will most likely still have those in stock. Not 100% positive but I thought the part number was 801.
 
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Good question for sure. I thought they ran chrome till it ended with Poulan, but I'm probably way off lol.

Not sure of the model year, but the P51 I just finished fixing up was fitted with a Mahle cylinder bore which looked like Nikasil. Beautifully made top end; piston rings are only ~ 0.040" thick. I found a NOS set, which reduced the ring end gap from 0.095" to 0.067". The ring pins abut the ring gap.

Compression after reassembly is ~ 160 PSI. V difficult to pull over without comp release

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Not sure of the model year, but the P51 I just finished fixing up was fitted with a Mahle cylinder bore which looked like Nikasil. Beautifully made top end; piston rings are only ~ 0.040" thick. I found a NOS set, which reduced the ring end gap from 0.095" to 0.067". The ring pins abut the ring gap.

Compression after reassembly is ~ 160 PSI. V difficult to pull over without comp release

View attachment 782281 View attachment 782282 View attachment 782283 View attachment 782284 View attachment 782287
It turned out great. A little timing advance makes them run better, and also easier to start.
 
It turned out great. A little timing advance makes them run better, and also easier to start.

Thanks!

"Timing Advance"....assume you mean cylinder port timing? Perhaps raising the ex port a bit?

(I do have a degree wheel, but didn't check the P51, as I had no reference port timing numbers. I also have zero experience with reed valve motors. Happy to learn, though...)
This thing is unbelievably tough to crank. Sore shoulder from a 4 pull compression test! Surprised to see "only" 160 psi - its that tough. Can't imagine when the rings bed in.
BTW, I did use a base gasket, and didn't check the squish. I believe the top end, etc is all original.

Anyone know how to interpret the (tag photo) serial number for production date?
 
Thanks!

"Timing Advance"....assume you mean cylinder port timing? Perhaps raising the ex port a bit?

(I do have a degree wheel, but didn't check the P51, as I had no reference port timing numbers. I also have zero experience with reed valve motors. Happy to learn, though...)
This thing is unbelievably tough to crank. Sore shoulder from a 4 pull compression test! Surprised to see "only" 160 psi - its that tough. Can't imagine when the rings bed in.
BTW, I did use a base gasket, and didn't check the squish. I believe the top end, etc is all original.

Anyone know how to interpret the (tag photo) serial number for production date?
Just a little off the flywheel key is all. They do respond quite well to some mild porting though. Can't tell the date of manufacture from that tag. Some will say the year, and that's as close as you can get with these. Roughly 1977 to 1982 though to give you a idea of the timeline for the p51. It's by far one of my favorite p series saws to run.
 
Just a little off the flywheel key is all. They do respond quite well to some mild porting though. Can't tell the date of manufacture from that tag. Some will say the year, and that's as close as you can get with these. Roughly 1977 to 1982 though to give you a idea of the timeline for the p51. It's by far one of my favorite p series saws to run.

Appreciate the notes!
Gosh; I should have thought that advancing the ignition timing would make this P51 even tougher to start. A couple years ago I retrofitted an old Bultaco 250 Pursang with an electronic advance module, which backed off (retarded) initial fixed timing by about 15 degrees. This made a difficult starting/rough idling old 2 stroke dirt bike into a pussycat. Maybe Pioneer saws are different?
Any way to measure actual ign timing on these without a timing light/degree wheel?
Back in the bad old days, some ported 2 stroke race bikes I messed with had exhaust ports raised so high (ie; exhaust timing advanced so much) that they would only start with a huge running bump start (not enough effective compression left to kick start)
 
looks Great, is that paint or powder coat.
Very good job.
Nothing special - PPG 2K urethane clear over rattle can base coat. Powder coating would be much better, I think.
Having now fixed up this lovely old Canadian saw, I can understand folks going to the expense and trouble of powder coating. These classic Pioneer saws are worth it, IMHO

Here's Harvey of Ironhorse - a real chainsaw expert - who certainly agrees. Worth a watch:

 
Appreciate the notes!
Gosh; I should have thought that advancing the ignition timing would make this P51 even tougher to start. A couple years ago I retrofitted an old Bultaco 250 Pursang with an electronic advance module, which backed off (retarded) initial fixed timing by about 15 degrees. This made a difficult starting/rough idling old 2 stroke dirt bike into a pussycat. Maybe Pioneer saws are different?
Any way to measure actual ign timing on these without a timing light/degree wheel?
Back in the bad old days, some ported 2 stroke race bikes I messed with had exhaust ports raised so high (ie; exhaust timing advanced so much) that they would only start with a huge running bump start (not enough effective compression left to kick start)
I know it sounds crazy, but it's worked good on my Pioneers and a couple ported Huskys.
 
Thanks!

"Timing Advance"....assume you mean cylinder port timing? Perhaps raising the ex port a bit?

(I do have a degree wheel, but didn't check the P51, as I had no reference port timing numbers. I also have zero experience with reed valve motors. Happy to learn, though...)
This thing is unbelievably tough to crank. Sore shoulder from a 4 pull compression test! Surprised to see "only" 160 psi - its that tough. Can't imagine when the rings bed in.
BTW, I did use a base gasket, and didn't check the squish. I believe the top end, etc is all original.

Anyone know how to interpret the (tag photo) serial number for production date?


The production period for P51 was 1978-1980 year. My P51 saws all have Metal Data plate on underside case half mounted and are dated 1978 thru 1980. Built here in Peterborough. the Cyls are chrome plated. l am just thinking your saw maybe late 1980 only because of the Data and cyl coating.
 
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