My dad has a 272xp that he rebuilt with an aftermarket p&c last fall. Even before he rebuilt it it never had the power it had when he first had it. It didnt get better after he rebuilt it. The other day I checked it with the tachometer and we couldnt get it above 10,500 rpm WOT. It seems to run good at that rpm but doesnt have good power. I no saws arent as good with cheep p&c but 3000 rpm low seems really bad. Has anyone else had a similar problem or know what could cause this.
Questions about a 272XP
- Thread starter Maplekid
- Start date
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thesawprofessor
ArboristSite Lurker
I'd check the carb first. Try re-adjusting it. If not it than I would try cleaning it out very thorough & put a rebuild kit in if needed. The ethanol in the fuel these days really does a number on those older carbs. Also, the screens in the mufflers can clog up & cause it to run slow.
gsg
ArboristSite Operative
If it ran higher before I would think a carb kit might be in order. The after market p&c should not effect rpm's.
cat-face timber
Knot Bumper
+1 on the carb kit
Especially the small screen in the carb......
Especially the small screen in the carb......
IthacaMan
ArboristSite Operative
Did you try leaning the carb to see if rpms go up?
IthacaMan
ArboristSite Operative
Also was the aftermarket P&C a 50mm or the stock 52mm?
Boleclimber
ArboristSite Guru
272xp came with a 52mm bore. 268XP and 268 came with 50mm bore. Regardless, bore diameter will not effect the ability to reach 13,500 RPM.
Porting numbers could effect tuning though. My impression is the same as others, Carb rebuild. 10,500 seems awful low for rpm, it would take very small port durations to come up with that RPM. .
Porting numbers could effect tuning though. My impression is the same as others, Carb rebuild. 10,500 seems awful low for rpm, it would take very small port durations to come up with that RPM. .
272super
ArboristSite Operative
I just had a 61 and 266 that would not rev out past 10,000. It turned out they both had air leaks at the intake block-to cylinder gasket. Did you do a vac or pressure test after the rebuild? If not you are taking a big chance that the saw is airtight. If you test the saw,do it with intake block attached to test that area. You could also have a bad seal or base gasket leak.
