Ax-man
Addicted to ArboristSite
I have been dragging my heels about posting this thread but here we go for a better or worse discussion.
I was going to sell this saw last year but the deal went south because the buyer never showed up . I got the saw running after sitting around for a long time. I told the buyer it was going to need work because it didn't run right . The guy never showed up so I just drained the gas shelved the saw with a tag saying needs carb work , air leak.
I pulled it back off the shelve recently . Carb air tested ok . I decided to see if it had an air leak . I had the gaskets made because I have been down this road before with these old Homelites. Blocked off the carb and muffler , piston on BDC, hooked up spark plug air line adaptor to the M/V and came up with a big fat O on the gauge. No big surprise there either because I have never had any luck with a P/V test on these Homelites going through the spark hole. I have never messed around with the seals on these old Homelites or anything to do with engine because they don't bring much for resale . I changed a piston once on a EZ . The most I do to these old saws is carb work , fuel lines and filters. This is usually enough to get them to at least run decent but not perfect.
I didn't want to tear this saw down any further just to find a seal leak because these saws aren't as easy to do like a Stihl to remove the flywheel and clutch. I have the tools to do it but I am not really planning on fixing it . The only reason I have the saw is because it has one of those trail clearing bow bars on it . The bar is worth more than the saw .
Where is all this going . I decided to do something different to see where it is leaking . I got my leak down tester out to see if I could hear where it was leaking . The tester in the pic is not a true " leak down tester for 4 stoke engines" . I do have the restrictor or damping valve and 2nd gauge that couples to the tester in the pic to do an actual leak down test on a 4 stroke. You don't need that stuff for a chainsaw . You can do the same thing with a regulator on an air compressor and the right fittings . I just don't like messing around with my compressor gauges so I use this set-up and it is easier to read.
Now for the big moment. I get my tester hooked up to the compressor bring the pressure up to a little less than 10 lbs. Then I hook the airline up and the gauge goes down to O again , just like the M/V test . This time I hear air rushing out just behind the clutch and a little on the flywheel side . If I wanted go to the extreme I could dunk the engine in a 5 gallon bucket of water to see exactly where it is leaking but I didn't . I always wanted to do that but this isn't the engine to try that on.
Now where is all this going , no where really except that I have always wanted to do this to a saw but never had the need to and might be helpful to someone else if they encounter the same problem. It just saved me from tearing the saw down any further and I was for the most part able to find the leak without soapy water and didn't have to pump on the M/V. If I was serious I would tear the saw down further and use this testor method to find the leak because the M/V method probably wouldn't be able to pump enough air to keep up with the leak.
Here are some pics to look at . I can add a little more to this thread if anyone is really interested because I actually did an actual leak down test on the piston and cylinder to see if it corresponded to the compression test I did on the saw. I think this is enough for now.
I was going to sell this saw last year but the deal went south because the buyer never showed up . I got the saw running after sitting around for a long time. I told the buyer it was going to need work because it didn't run right . The guy never showed up so I just drained the gas shelved the saw with a tag saying needs carb work , air leak.
I pulled it back off the shelve recently . Carb air tested ok . I decided to see if it had an air leak . I had the gaskets made because I have been down this road before with these old Homelites. Blocked off the carb and muffler , piston on BDC, hooked up spark plug air line adaptor to the M/V and came up with a big fat O on the gauge. No big surprise there either because I have never had any luck with a P/V test on these Homelites going through the spark hole. I have never messed around with the seals on these old Homelites or anything to do with engine because they don't bring much for resale . I changed a piston once on a EZ . The most I do to these old saws is carb work , fuel lines and filters. This is usually enough to get them to at least run decent but not perfect.
I didn't want to tear this saw down any further just to find a seal leak because these saws aren't as easy to do like a Stihl to remove the flywheel and clutch. I have the tools to do it but I am not really planning on fixing it . The only reason I have the saw is because it has one of those trail clearing bow bars on it . The bar is worth more than the saw .
Where is all this going . I decided to do something different to see where it is leaking . I got my leak down tester out to see if I could hear where it was leaking . The tester in the pic is not a true " leak down tester for 4 stoke engines" . I do have the restrictor or damping valve and 2nd gauge that couples to the tester in the pic to do an actual leak down test on a 4 stroke. You don't need that stuff for a chainsaw . You can do the same thing with a regulator on an air compressor and the right fittings . I just don't like messing around with my compressor gauges so I use this set-up and it is easier to read.
Now for the big moment. I get my tester hooked up to the compressor bring the pressure up to a little less than 10 lbs. Then I hook the airline up and the gauge goes down to O again , just like the M/V test . This time I hear air rushing out just behind the clutch and a little on the flywheel side . If I wanted go to the extreme I could dunk the engine in a 5 gallon bucket of water to see exactly where it is leaking but I didn't . I always wanted to do that but this isn't the engine to try that on.
Now where is all this going , no where really except that I have always wanted to do this to a saw but never had the need to and might be helpful to someone else if they encounter the same problem. It just saved me from tearing the saw down any further and I was for the most part able to find the leak without soapy water and didn't have to pump on the M/V. If I was serious I would tear the saw down further and use this testor method to find the leak because the M/V method probably wouldn't be able to pump enough air to keep up with the leak.
Here are some pics to look at . I can add a little more to this thread if anyone is really interested because I actually did an actual leak down test on the piston and cylinder to see if it corresponded to the compression test I did on the saw. I think this is enough for now.
