MCCULLOCH The official McCulloch thread

[Rio95]

Thanks everyone for the tips - we've got spark!!!

Everything checked out well with 0.20 gap on the points, set the air gap to the flywheel to 0.10 with a feeler guage, points clean, multimeter showed them opening and closing, etc. Except the secondary coil, no matter the range on the multimeter, I couldn't get a reading, but Al's comment about them being bulletproof made me check everything again... Turns out you've got to spin the flywheel the right way... I underestimated my own stupidity.

Anyway, I've got a hot blue spark when I put the drill in reverse...

 

[hacskaroly]

Al's comment about them being bulletproof made me check everything again... Turns out you've got to spin the flywheel the right way... I underestimated my own ability.

I fixed it. Congrats on getting everything squared away. Stuff happens! I was working on a new (new to us) antenna we received from an Air National Guard unit for a Tacan in Iraq. Spun it up and everything was good except for where our monitor antenna was wanting to be positioned and still would not dial in. Finally I had a thought it might be running backwards. Swapped two power leads, got it spinning the other way and bam, everything was working as it should. It appeared that someone did some maintenance at some point and got the two black leads mixed up....oops!

 

[Rallyeguy]

I fixed it. Congrats on getting everything squared away. Stuff happens! I was working on a new (new to us) antenna we received from an Air National Guard unit for a Tacan in Iraq. Spun it up and everything was good except for where our monitor antenna was wanting to be positioned and still would not dial in. Finally I had a thought it might be running backwards. Swapped two power leads, got it spinning the other way and bam, everything was working as it should. It appeared that someone did some maintenance at some point and got the two black leads mixed up....oops!

Any time I have a 50/50 electrical connection option.....There's a 95% chance I get it wrong

 

[Al Smith]

As far as the coil on a 105 it could be the large coil like a 250 or a small coil like a 10-10 .One of my 125's had an "atom arc " solid state trigger device and a 2.5 degree off set key which should have advanced the timing to around 28 or so advance from the original 26 advance .The device was basically glued in place and became loose rendering it not functional .As luck would have it the points and condenser were still in place which I then used . As far as the additional advance compaired to my other 125 I really can't tell the difference .Both start relatively easy and seem to produce about the same power . But keep in mind those old school Paul Bunyan saws are not cant cutters more so old school redwood slayers ,torque monsters .

 

[Sloughfoot]

Got all the parts gathered, cleaned and am ready to start building this 10-10 when time allows. I'll do some light porting on this weird cylinder beforehand. I'm seeing reputable builders bring the 4 larger transfers down 3/4" or so and open up the exhaust port. Any of you done more than that on one of these?

 

[Rallyeguy]

Mark Heimann will appreciate this..... Added Viton Fuel Tank 10 series Gasket as an option in my store. Can go with either Cork (OEM style), or the newer Viton. Selection is available with any kit that carries the cork. https://www.oldsawshop.com/McCulloch-Gasket-Seal-&-Carburetor-rebuild-kit-p714508763

 

[Sloughfoot]

Mark Heimann will appreciate this..... Added Viton Fuel Tank 10 series Gasket as an option in my store. Can go with either Cork (OEM style), or the newer Viton. Selection is available with any kit that carries the cork. https://www.oldsawshop.com/McCulloch-Gasket-Seal-&-Carburetor-rebuild-kit-p714508763

Viton is good stuff. Just got a kit from you and have cork. May have to get a viton one from you in the future.

 

[Rallyeguy]

Personally I've always liked the cork but if you store your saws dry, I believe that over time it could potentially dry out which might break the seal. Figured I had access to the Viton, so I may as well offer both....

 

[Bigmac]

As far as the coil on a 105 it could be the large coil like a 250 or a small coil like a 10-10 .One of my 125's had an "atom arc " solid state trigger device and a 2.5 degree off set key which should have advanced the timing to around 28 or so advance from the original 26 advance .The device was basically glued in place and became loose rendering it not functional .As luck would have it the points and condenser were still in place which I then used . As far as the additional advance compaired to my other 125 I really can't tell the difference .Both start relatively easy and seem to produce about the same power . But keep in mind those old school Paul Bunyan saws are not cant cutters more so old school redwood slayers ,torque monsters .

The timing isn’t advanced when using points, only when using the chip and the advanced key

 

[Al Smith]

That is a difference of opinion and theory .The off set key controls the position of the flywheel which is shifted forward .However the atom arc device fires when it reachs the highest voltage in the wave form so it fires advanced .However if you "maverick" " the points ,set them wider by a few thou they open slightly advanced and also fire early .I figured by maybe 2.5-3 degrees .Much more they won't close all the way and thus never fire .I've got a real early 6-10 which is a variation of the 10-10 but right hand start and 70 CC's .I have it around 30-31 degrees advance and it will dead stick at slightly over 15,000 RPM . It some times is rather hard to start which is a little tough on your fingers to say the least .That saw BTW is only an experiment that I seldom use because running that fast it won't last very long if used a lot .

 

[Bigmac]

That is a difference of opinion and theory .The off set key controls the position of the flywheel which is shifted forward .However the atom arc device fires when it reachs the highest voltage in the wave form so it fires advanced .However if you "maverick" " the points ,set them wider by a few thou they open slightly advanced and also fire early .I figured by maybe 2.5-3 degrees .Much more they won't close all the way and thus never fire .I've got a real early 6-10 which is a variation of the 10-10 but right hand start and 70 CC's .I have it around 30-31 degrees advance and it will dead stick at slightly over 15,000 RPM . It some times is rather hard to start which is a little tough on your fingers to say the least .That saw BTW is only an experiment that I seldom use because running that fast it won't last very long if used a lot .

Setting the points gap larger will advance the timing. Maverick timing is essentially the points floating open at rpm, difficult to quantify, would need to check with a timing light to know The timing when checked with a degree wheel have usually maxed out at 28° before they hang open, checked with a degree wheel. Most are 26° with standard settings. A standard flywheel is centered up in the coil at about 26° and the 5° flywheel is 31°
If your saw is starting and preforming the same you’re not achieving any advance. It’s a noticeable difference in standard to 5° flywheels with a chip, both in starting and preforming. As an fyi every .010 off the key is 2.5°
With a chip a 5° flywheel and .010 off the key should get you 33.5° on the 125 and 101’s 5° flywheels with a chip can be hard to start on the karts.

 

[Al Smith]

--which is why back in the day on the kart 101'is they used a starter cup with a long shaft Ford starter and a vee belt .That goes back in time a day or two .Like I said I only bumped up the one 125 a little bit which is the one I sleeved with a cast iron sleeve .That goes back at least 15 years and since I have not ran that saw enough to seat the rings .I have no idea what that saw RPM's are ,fast enough for me .That said the novelty of a large saw does not last that long ,danged things are heavy. Plus there aren't that many 4 foot trees in Ohio . The stump I'm on in the avatar picture was one and the saw is a rare
2100 S Homelite,.

 

[NZsaws]

Picked up a 850 at $180 US looking worse for wear.
Rubbers are worn and smokes like a train but has great compression and seems to oil.
Maybe im a sucker

 

[hacskaroly]

looking worse for wear.
Rubbers are worn and smokes like a train but has great compression and seems to oil.

Shoot, that one doesn't look too bad at all. Looks like it needs a little TLC, but otherwise it appears to be in great shape!!

 

[NZsaws]

Yeah she's a bit rough but if can find new mounts should fix up ok.
Starts fine,

 

[heimannm]

I have the AV mounts if you can't find them locally. White smoke normally indicates the automatic oil pump is not properly sealed and it is pulling some bar oil into the crankcase.







Mark

 

[NZsaws]

Howdy Mark.
This is the saw I asked you about a few weeks back.
So going by that, I'm missing the spring and also the eyelets?
Also see the little round plug that came out of the oil tank, is this a stray part?
I presume you can make the spring out of some steel sheet?
Cheers.

 

[NZsaws]

Found you thread on AS re the oiler so this covers it all.
You should write a book!

 

[Al Smith]

Often times on those Mac impulse pumps on a cold start they will puff smoke until it burns the residual left in the crankcase .Then just clean up and run normal .Some times the good old kerosene flush will help them,some times not .Rebuild kits used to be available but I'd imagine by now they are in short supply .That said usually the 82's are good cutters,fast enough although not like a more modern design .They will handle a 32" bar with relative ease .I was gifted a 36" bar with a 50 thou groove fitted with a .404 sprocket nose which I changed to 3/8" nose .I suspect it was once a west coaster . However I've never used it .Usually my 3 82's wear 24" bars running 7 tooth rims .

 

[heimannm]

The round plug that was rattling around loose came out of the oil cap.



Seems you have answered the rest of the questions.

Knightmax has invested and has the eyelets and spring clip kits, hopefully your 92818 seal is still in good condition.

I have a few of the full 215246 kits with the 92818 seal, eyelets, and spring clip.

Mark