Dan hensley
ArboristSite Lurker
Hello all!
First time poster here, however I have used this site and its many forms so many times. This has been so helpful over the years and usually with enough digging I can find exactly what I’m trying to trouble shoot with a saw!
This past year I received an ms 084 av from an older gentleman that happened to take notice of my love for all things forestry. According to the guy that saw had sat for 10 years at least. Well this year I finally got around to tearing into this big boy.
Findings
The good- upon inspection I have found a perfect OEM piston( still has machine marks) and cylinder. Compression tested out at 185 psi and I can start to understand why the old timer didn’t pick it up much in his last years of logging here in the mid west hardwoods. The spark seemed good visually, but I was concerned as I had read that the coils with an additional igniter module while unlimited a lot of times would give out more rapidly. The concern I had for the coil caused me to take it a step further and to test the resistance which checked out perfectly.
The bad- fuel line was rotted out from old gas and carb gummed up as well. Unfortunately this old hog lost its muffler apparently in the woods a few years before its retirement and now sports a piped exhaust which scares the crap out of me on a saw this big! Good buy some good ear plugs for the first time.
The ugly- I went ahead and pressure tested the saw and it had leaks yes leaks not just one. Both oil seals had gone bad and there was pass through from the crank case gasket into the oil tank.
So I split the case and put in a new gasket as well as a new cylinder gasket and new set of rings. I replaced the fuel lines, impulse hose, and put a carb kit in it. Put in new oil seals retested pressure and it tested out good. I went ahead and changed out the tank vent as well as I read the garb screw style have been know for trouble
Now I’ve been beating my head off of the work bench for about two weekends worth of work now from this next part. I put the carb to factory settings put in fresh fuel a little rich for break in 40:1 ams oil saber. Pushed in the decomp and pulled to eternity. Got zero fire so I finally put a shot fuel down the carb and BANG! She went. Burned up that fuel and died out. Went again shot down the pipe of fuel bang then dies out. I sat down on the bench tonight and watched the fuel line closely as it is a more see through line I installed. I’ve never experienced this before but every time I pull the saw over on choke the fuel starts to rise in the fuel line but then actually gets further away. When switched to just regular run and pulled over the fuel just sits still in the fuel line and doesn’t move. I believe it or not already had a spare OEM carb for an 084 parts saw so for ***** and gigs I swapped it out and yes it had a fresh carb kit in it as well. Unfortunately swapping the carb some I still am having the same problem. I don’t understand how this can be acting this way after all new rubbers and a carb rebuild kit has been installed amongst all the other things that I have done for the saw.
If someone can help me out with this one before I go insane I would greatly appreciate it!!!!!
Side not these are both the very first style of carbs offered on the ms 084
First time poster here, however I have used this site and its many forms so many times. This has been so helpful over the years and usually with enough digging I can find exactly what I’m trying to trouble shoot with a saw!
This past year I received an ms 084 av from an older gentleman that happened to take notice of my love for all things forestry. According to the guy that saw had sat for 10 years at least. Well this year I finally got around to tearing into this big boy.
Findings
The good- upon inspection I have found a perfect OEM piston( still has machine marks) and cylinder. Compression tested out at 185 psi and I can start to understand why the old timer didn’t pick it up much in his last years of logging here in the mid west hardwoods. The spark seemed good visually, but I was concerned as I had read that the coils with an additional igniter module while unlimited a lot of times would give out more rapidly. The concern I had for the coil caused me to take it a step further and to test the resistance which checked out perfectly.
The bad- fuel line was rotted out from old gas and carb gummed up as well. Unfortunately this old hog lost its muffler apparently in the woods a few years before its retirement and now sports a piped exhaust which scares the crap out of me on a saw this big! Good buy some good ear plugs for the first time.
The ugly- I went ahead and pressure tested the saw and it had leaks yes leaks not just one. Both oil seals had gone bad and there was pass through from the crank case gasket into the oil tank.
So I split the case and put in a new gasket as well as a new cylinder gasket and new set of rings. I replaced the fuel lines, impulse hose, and put a carb kit in it. Put in new oil seals retested pressure and it tested out good. I went ahead and changed out the tank vent as well as I read the garb screw style have been know for trouble
Now I’ve been beating my head off of the work bench for about two weekends worth of work now from this next part. I put the carb to factory settings put in fresh fuel a little rich for break in 40:1 ams oil saber. Pushed in the decomp and pulled to eternity. Got zero fire so I finally put a shot fuel down the carb and BANG! She went. Burned up that fuel and died out. Went again shot down the pipe of fuel bang then dies out. I sat down on the bench tonight and watched the fuel line closely as it is a more see through line I installed. I’ve never experienced this before but every time I pull the saw over on choke the fuel starts to rise in the fuel line but then actually gets further away. When switched to just regular run and pulled over the fuel just sits still in the fuel line and doesn’t move. I believe it or not already had a spare OEM carb for an 084 parts saw so for ***** and gigs I swapped it out and yes it had a fresh carb kit in it as well. Unfortunately swapping the carb some I still am having the same problem. I don’t understand how this can be acting this way after all new rubbers and a carb rebuild kit has been installed amongst all the other things that I have done for the saw.
If someone can help me out with this one before I go insane I would greatly appreciate it!!!!!
Side not these are both the very first style of carbs offered on the ms 084