Heard my project 101 running today for the first time. I got all the parts I needed from Duncan's. It all but destroyed my pull starter rope and my spare recoil so any more fun and games will have to wait till I can get them fixed. I'm going to redo all my mac recoils while I'm at it. I'll be honest I'll probably have em fixed at a local shop because I hate recoils. Hopefully they'll holdup. The BDC carb works fine just a little more tuning to go, MAN will she wind! It runs good enough to start mocking up the saw and I'll post pics when I get the pipe on her, can't wait to hear that. I'm having too much fun. Jared
Mac hotsaw progress
- Thread starter GOBRDGO
- Start date
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Lawn Masters
Addicted to ArboristSite
I know how that feels, Recoils are my weak point too, I absolutely ?HATE repairing them. anything else I'm more than willing to do though.
ozflea
Good ol' BP Zoom 25-1
Gee you fellas are whimps, nothing like a replace starter spring first thing in the morning it makes ya day.
Mc Bob.
Mc Bob.
I think I broke a starter spring, I'm in the hunt for one. Hopefully I don't break the pulley trying to remove the thing that engages the pawls in order to get the spring. Only a mac guy would know what I'm talking about.
Stihl 041 super
ArboristSite Operative
3 min
I know a guy who can fix almost any recoil in 3 minutes.
I know a guy who can fix almost any recoil in 3 minutes.
ozflea
Good ol' BP Zoom 25-1
Kick starting a Mc101
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I posed the question on another forum called hand starting a Mc 101 and heres the reply i got from Steve O'Hara ace McCulloch man on Kart engines.
Starting with my question.
Well Steve this 101 i own is a brute of a thing and since i'm not built like the back end of a bus how do i start this thing by hand starter, i know that i should keep the head close to the piston but even with a decompressor fitted it near tears my arm out of it's socket as it blows the decompressor closed after the first pass that wacko Bob's on his way to hospital armless again.
Can i find a way of lowing the compression and still have a competitive engine or do i do away with the hand starter and go electric start, ie 12v car engine starter.
I feel that if i persist in trying to hand start this beast i'll only end up with a heap of broken bits and pieces.
What thickness in head gaskets are there to assist in adjusting it to something more suitable.
Mc Bob.
P.S You were right about that Galvin manifold and the BDC's i may have to make something to suit the top of my V12 reed manifold as i have one already.
How would 2 BDC's go on top of the V12 providing i got the adaptor machined up ??
_________________
The one eyed Mac Man from downunder
Steves Responce.
Bob,
If it were me I would design and fabricate an on board starter powered by a compressed gas canister like they use to charge up paint ball guns.
Of course that would take a bit of engineering and fabrication skill that may be unavailable so here is another idea.... the problem is not that there is too much compression... it is that the motor wants to fire on that first pop and you don't have enough torque or inertia to carry through the top part of the stroke and get the combustion working for you. The solution is to rig up a simple kill switch with "doorbell" type switch. Mount it so you can hold it down with your thumb or one finger of the hand you use to hold the saw and wire it to the "off" position while it is depressed. Hold the button down while you yank the recoil handle and let it up after the motor is cranking over.... basically as you are nearing the end of the full pull of the rope. I'm betting you would find that you can get a full pull of the rope without kick back if you have no spark so the trick is to disable the spark until you have the motor spinning and you are ready to let go of the handle.
Hope this idea helps..... let me know how it works out.
Regards,
Steve O'Hara
Hope this info helps out my fellow Mc 101 lovers who wish to save on starter ropes and starter components.
Mc Bob.
--------------------------------------------------------------------------------
I posed the question on another forum called hand starting a Mc 101 and heres the reply i got from Steve O'Hara ace McCulloch man on Kart engines.
Starting with my question.
Well Steve this 101 i own is a brute of a thing and since i'm not built like the back end of a bus how do i start this thing by hand starter, i know that i should keep the head close to the piston but even with a decompressor fitted it near tears my arm out of it's socket as it blows the decompressor closed after the first pass that wacko Bob's on his way to hospital armless again.
Can i find a way of lowing the compression and still have a competitive engine or do i do away with the hand starter and go electric start, ie 12v car engine starter.
I feel that if i persist in trying to hand start this beast i'll only end up with a heap of broken bits and pieces.
What thickness in head gaskets are there to assist in adjusting it to something more suitable.
Mc Bob.
P.S You were right about that Galvin manifold and the BDC's i may have to make something to suit the top of my V12 reed manifold as i have one already.
How would 2 BDC's go on top of the V12 providing i got the adaptor machined up ??
_________________
The one eyed Mac Man from downunder
Steves Responce.
Bob,
If it were me I would design and fabricate an on board starter powered by a compressed gas canister like they use to charge up paint ball guns.
Of course that would take a bit of engineering and fabrication skill that may be unavailable so here is another idea.... the problem is not that there is too much compression... it is that the motor wants to fire on that first pop and you don't have enough torque or inertia to carry through the top part of the stroke and get the combustion working for you. The solution is to rig up a simple kill switch with "doorbell" type switch. Mount it so you can hold it down with your thumb or one finger of the hand you use to hold the saw and wire it to the "off" position while it is depressed. Hold the button down while you yank the recoil handle and let it up after the motor is cranking over.... basically as you are nearing the end of the full pull of the rope. I'm betting you would find that you can get a full pull of the rope without kick back if you have no spark so the trick is to disable the spark until you have the motor spinning and you are ready to let go of the handle.
Hope this idea helps..... let me know how it works out.
Regards,
Steve O'Hara
Hope this info helps out my fellow Mc 101 lovers who wish to save on starter ropes and starter components.
Mc Bob.
Al Smith
Addicted to ArboristSite
Good idea,but timing would be the key.I've thought of something like that on my 6-10.It's only a scant 4.3 cu inch but with advanced timing and that smaller rope drum,it comes back atya worse than an sp 125,really.I hate to reset the timing to factory specs because it runs soooo good 
ozflea
Good ol' BP Zoom 25-1
Mc 101's and Dentist's have one thing in common both require a bit of pain to get the job done.
Mc Bob.
Mc Bob.
I received the tuned pipe for her today, Very cool, I still got the pullstart blues but I haven't given up yet. The carb began to puke raw fuel and I found a swelled up duckbill valve. I pulled the tip to remove it and it broke. I guess I need to hook up with Bob's source and buy a dozen or so. The real problem was a loose screw that holds the shaft that controls the needle and stuff. Sorry about my terminology. The good news is I can start building the rough draft saw while I wait for some parts (bar,chain and carb stuff) because now I know the motor is a runner.
ozflea
Good ol' BP Zoom 25-1
Yes Jareb those old origional Duckbill valves done a great job in their day but thats been long gone and the new ones are made of better material after all twenty years have transpired and are a lot less prone to swelling, anyway the break will give your body a rest till the next test.
Mc Bob.
Mc Bob.
