|
Post by daveyj65 on Jul 26, 2011 18:33:40 GMT -5
I have an XL12 I, rebuilding the carb, and while its apart checked compression it was 90lbs. What should it be? I'm a newbie here read alot of other post very glad to of found you guys thanks
|
|
|
Post by MCS on Jul 26, 2011 19:08:51 GMT -5
Compression should be quite a bit higher than 90. Homelite Shop Service Manual's state that at 90 it's time for some work. Have you pulled the muffler and looked at that side of the piston? Are you sure your compression gauge is accurate? Is it a screw in gauge?
|
|
|
Post by tribulation138 on Jul 26, 2011 20:17:54 GMT -5
On my pioneer i did a compression test with the carb out, reeds out and no carb box. i figured it would read a good psi after rebuilding the engine. it didnt at all 110psi. so put the reeds and carb back on along with carb box. it read 185psi
|
|
|
Post by MCS on Jul 27, 2011 6:51:59 GMT -5
Yup, the reeds have to be in place so the crankcase can charge the cylinder on the down stroke.
|
|
|
Post by daveyj65 on Jul 27, 2011 11:14:52 GMT -5
I do have the carb out didnt know this would change measurement on compression.m Also I'm using my auto compression guage. it is a screw in . I will get back soon as i put carb in. tHANKS dAVE
|
|
|
Post by daveyj65 on Jul 27, 2011 12:59:11 GMT -5
Ok I put good carb back on saw, Checked piston thru exhaust Dark in color at top, probably running too rich or something, The rest of the piston looks decent for the age. No signs of scalding or groves. Because the rest of the saw was apart, I just used my cordless drill with socket and from pull cord side used drill to rotate cam. It started out with a quick 30# then as I kept the revolutions going it climbed to a 120# thats where it held. it actually held compression for a couple min. did'nt wait to see how long it would hold. Any ideas need to get running up to snuff soon Thanks Dave
|
|
|
Post by MCS on Jul 27, 2011 14:20:16 GMT -5
It held compression? Did you release the valve on the gauge? It should be fine. The maximum compression reading is somewhat dependent on how fast the engine is spun around and did you lock the trigger open? I'd put it together and run it...
|
|
|
Post by daveyj65 on Jul 27, 2011 18:49:01 GMT -5
I released the valve to put the spark plug back in I have an identical sister to this saw. I tested it pulling by hand on pull cord and it read 120# also They both have been used about the same amount. I bought these many many years ago and have used them religiously , Generally about 14- 17 cords of wood each year. They don't seem to be as agressive as they used to be And I thought maybe it was the compression. What are your thoughts
|
|
|
Post by tribulation138 on Jul 27, 2011 21:37:29 GMT -5
make sure chain is sharpened... tune carb for max power. To rich on high speed needle will bog the engine at full throttle. Just dont make it to lean.
the xl-12 is great saw at 54cc's. But remember its only a light duty saw. I know xl-12 series saw run decent at 120-150psi. But 120 is just alittle bit to low for me IMO. I like my saws to run at 165-190psi. The result is the saw cuts bigger, faster, and just torquier.
|
|
|
Post by daveyj65 on Jul 28, 2011 7:20:23 GMT -5
Tribulation, Thanks For The Tip I belive I am going to re-ring the saws And hopefully boost compression. I have a Super 1050 and boy you talk about compression. If you aren't careful and don't have a good hold on pull cord it will hurt you. Again thanks
|
|