Picked up a Pioneer 620 saw about a month or so ago and have been working to get it up and running again. It has good spark and 150psi compression. I cleaned/rebuilt the carb with a new carb kit, new fuel lines and fuel filter, new spark plug, etc. Got it to fire and run, but it won't run very well. It will idle pretty good and it will rev up a bit, but it will not rev out when holding the throttle open. Figured my next step was to run a pressure/vacuum test.
I blocked off the intake and exhaust ports with some rubber gasket material and used a special fitting in the spark plug hole to pump air into the engine. I picked up a Mityvac 8500 a few weeks ago so I used that to run the pressure test.
Started pumping air into the engine and immediately after just a few pumps I could hear hissing coming from somewhere. No matter how much I pumped, it would only go up to 4-5psi and then drop within a few seconds. I sprayed soapy water around the intake and exhaust ports, the spark plug hole, and around the base gasket and head gasket. No bubbles anywhere. My assumption then is the leak must be coming from the crank seals. I figured I'd run the test first just to see if there was a leak and if it was something easier to fix. Turns out it's not haha!
My next step will be to pull the flywheel off and the clutch off so I can get to each crank seal.
My questions are:
1.) What part numbers are the crank seals (assuming there are no NOS Pioneer crank seals)? I'm sure there are some available somewhere with the correct dimenstions.
2.) Is the flywheel nut regular or reverse thread?
3.) Is the clutch nut regular or reverse thread?
4.) Is there a specific puller that would work best vs a cheap Ebay one?
5.) Is there a gasket between the flywheel case half? I looked in the parts diagram and I don't see one. Maybe I could use some gasket maker?
Appreciate any help or suggestions as this will be my first time replacing crank seals on a chainsaw.
I blocked off the intake and exhaust ports with some rubber gasket material and used a special fitting in the spark plug hole to pump air into the engine. I picked up a Mityvac 8500 a few weeks ago so I used that to run the pressure test.
Started pumping air into the engine and immediately after just a few pumps I could hear hissing coming from somewhere. No matter how much I pumped, it would only go up to 4-5psi and then drop within a few seconds. I sprayed soapy water around the intake and exhaust ports, the spark plug hole, and around the base gasket and head gasket. No bubbles anywhere. My assumption then is the leak must be coming from the crank seals. I figured I'd run the test first just to see if there was a leak and if it was something easier to fix. Turns out it's not haha!
My next step will be to pull the flywheel off and the clutch off so I can get to each crank seal.
My questions are:
1.) What part numbers are the crank seals (assuming there are no NOS Pioneer crank seals)? I'm sure there are some available somewhere with the correct dimenstions.
2.) Is the flywheel nut regular or reverse thread?
3.) Is the clutch nut regular or reverse thread?
4.) Is there a specific puller that would work best vs a cheap Ebay one?
5.) Is there a gasket between the flywheel case half? I looked in the parts diagram and I don't see one. Maybe I could use some gasket maker?
Appreciate any help or suggestions as this will be my first time replacing crank seals on a chainsaw.
