thomas1
sodium pentothal
- Joined
- May 2, 2010
- Messages
- 3,651
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Not sure, yet. I didn't get to catch up with him yesterday, so it will probably be sometime next week.
Sorry to get everyone's hopes up.
McCulloch Chain Saws
- Thread starter Bruce Hopf
- Start date
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Not sure, yet. I didn't get to catch up with him yesterday, so it will probably be sometime next week.
Sorry to get everyone's hopes up.
Ckelp- some guys like to "sonic race" with their saws making the highest pitch noise possible. You can't do that with the fixed high jet, too rich. On the other hand, when you put it in the wood that rich saw cleans up and just keeps going...
Mark
Mark
Sounds like it might prevent a little damage also..
Warped5
WingNut
Is this the proper time line bar for the CP70? This is a nos bar I have, the one that came on it was similar, but had a bunch of paint wear.... not sure if it said Mac 10?
:beauty3:
ckelp
just being myself
dam, learn something new everyday
joeymt33
I bleed YELLOW!
I'm not a fan of them, I dont even consider those to be mcculloch. On the bright side though, they're very cheap to buy and they probably cut ok.
Warped5
WingNut
I'm no fan either. The last couple plasti-Macs I've opened looked to have made by Jenn Feng. Take a look at the coil, if it's got a big JF on it ...
Enough of the JF chinese Mac rip off crap....
1-72 CL Score!
Doug, no offense!
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Thats one clean 1-72 Doug.
Great find.
Lee
Great find.
Lee
cpr
Addicted to ArboristSite
Awesome 1-72! One of my all time favorites. Does it still have the Town & Country muffler?
Bypass the govenor and let that bad boy eat!
Bypass the govenor and let that bad boy eat!
Eccentric
Mister Wizard
My SP-81 has a fixed H-jet Walbro SDC like the one Joe pictured. IIRC it is an SDC52A. I have an SDC38A fully adjustable carb that I will swap on as soon as I can get myself to drill the carb box for the carb needle pass-through grommet. It does run pretty well with the current carb (as you've seen and heard) but I like to be able to adjust my carbs for different altitudes and other conditions.
It is funny that my SP-81 works fine both here and at the park we cut in (Bothe Napa Valley State Park), while my fully adjustable PM700 requires a retune when I go from one place to the other because of the elevation change. Tuned correctly at home, it's pig-rich at Bothe. Tuned right for Bothe, and it's very lean back at home. The SP-81 doesn't seem to care much other than seeming a tad too rich at park (on the H-side), but it needed a MAJOR retune on the L-side for it to run right at that elevation....
I agree. That saw is CHERRY.
I live in NH (Somersworth), saw lived in Needham...I have admired your saws for a while now, good stuff!
Eccentric
Mister Wizard
Ah the elusive Town and Country muffler. I believe Mark described the two settings as loud and LOUD.
As for the governor, it is an air vane type. The air vane arm (under the flywheel cover) has a spring that forces it towards the flywheel. The arm has a shaft that passes through the lower tank/carb box. On the end of that shaft is a forked arm that bears on a roller attached to the left side throttle shaft arm of the carb. Spring pressure on this governor hardware tries to open the throttle. The trigger has a strong spring that forces the trigger forward (which in turn pulls the throttle link back).
The throttle link attached to the trigger pulls back on the right side 'hooked' throttle arm of the carb because of this spring tension. The trigger spring is stronger than the governor spring, so the trigger 'wins' the 'tug of war' between the trigger and the governor. When you pull the trigger, the throttle link moves forward, allowing the throttle arm to move forward under governor spring pressure. Once the engine RPM's come up enough, the air vane is pushed away from the flywheel and the governor spring is overcome.....closing the throttle. When this happens, the hooked throttle arm rotates away from the throttle link.
Remove your flywheel cover, air filter cover, and air filter. Move the trigger and the air vane with your hand and watch everything to see how all the parts interact with each other. You'll understand it then. It's all a balancing act between two springs (trigger and governor) and the air vane.
On my saws, the governors were all disabled by prior owners cutting the vane off of the governor arm. The 'balancing act' between springs still happens (as the governor arm is still mostly intact, and still has its spring), but the governor arm no longer closes the throttle once the engine reaches a certain RPM as there's no vane to be pushed by the air coming off of the flywheel.
As for the governor, it is an air vane type. The air vane arm (under the flywheel cover) has a spring that forces it towards the flywheel. The arm has a shaft that passes through the lower tank/carb box. On the end of that shaft is a forked arm that bears on a roller attached to the left side throttle shaft arm of the carb. Spring pressure on this governor hardware tries to open the throttle. The trigger has a strong spring that forces the trigger forward (which in turn pulls the throttle link back).
The throttle link attached to the trigger pulls back on the right side 'hooked' throttle arm of the carb because of this spring tension. The trigger spring is stronger than the governor spring, so the trigger 'wins' the 'tug of war' between the trigger and the governor. When you pull the trigger, the throttle link moves forward, allowing the throttle arm to move forward under governor spring pressure. Once the engine RPM's come up enough, the air vane is pushed away from the flywheel and the governor spring is overcome.....closing the throttle. When this happens, the hooked throttle arm rotates away from the throttle link.
Remove your flywheel cover, air filter cover, and air filter. Move the trigger and the air vane with your hand and watch everything to see how all the parts interact with each other. You'll understand it then. It's all a balancing act between two springs (trigger and governor) and the air vane.
On my saws, the governors were all disabled by prior owners cutting the vane off of the governor arm. The 'balancing act' between springs still happens (as the governor arm is still mostly intact, and still has its spring), but the governor arm no longer closes the throttle once the engine reaches a certain RPM as there's no vane to be pushed by the air coming off of the flywheel.
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