JT78
ArboristSite Guru
You know we all want to see some video of that thing running.
You know we all want to see some video of that thing running.
I'll try to do that this week.
Wish I had a chance to run one (not just hear it idle and the throttle blipped) Brad got his mitts on.
Come on back up here and we'll go put that bad boy in that Oak we cut a few weeks ago. We could get some video of it.
Tomorrow evening sound good to you?
I'l give 'em a call. He's always up for a trip to Franklin.
Brad,No I wouldn't. He's no longer porting saws. I'm really just looking for clarification of my hunches.
Disclaimer: I did not do the port work on this saw!!!
A quick history here. This 3120 was bought brand new back in '04 by another forum member. It was ported, muffler modded, and the timing advanced. Shortly there after the offset keyway sheared. It hasn't run right since that time and has just sat all these years. I have it to sort it out and get it running good. I pulled a compression check and only got 110-115 PSI. However, the rings still look like brand new, with the little machine lines still in them. This saw never even got broken in.
None of the ports were widened. However, the exhaust was raised A LOT. The transfers were also raised considerably, and the intake lowered. I will be putting a degree wheel on it to see where it sets.
What happened to this saw? Notice all the odd markings in the cylinder and piston. Did this saw get real hot at one time, but not enough to seize? You can see the shape of the exhaust port roof on the piston skirt where the piston is at TDC. Was the port not deburred and beveled after porting, and marked the piston? There's one line to the right of the exhaust port on the cylinder wall that I can feel. Why is the compression so low? Exhaust too high?
It was only raised at the cylinder wall, and not tapered out to the flange.
Not widened at the cylinder wall at all. You see some finish sanding marks towards the flange. It was not widened.
Markings above the intake.
The transfers were the ugliest. There were a couple knicks I didn't quite remove. I didn't want to raise them any more. I did widen them towards the intake.
Very nice work in the transfers, did you get a 90° hand piece??
BTW I was right that 044 did out run the ole 460.
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