McCulloch Chain Saws

[rwoods]

Stinkbait, your 800 intake should have a small slot shaped cut out about 1/2 the way across the top of the intake. I can't find the instructions on how to google within this site but there are pictures that show the differences. The exhaust port includes a "ramped" area inside the cylinder that leads to the "Q"port. Ron

 

[rwoods]

Links:View attachment 191829View attachment 191830View attachment 191831View attachment 191832

 

[rwoods]

Ron

800 Intake Top
800 Exhaust
850 Left 800 Right
850 Left 800 Right

 

[stinkbait]

Stinkbait, your 800 intake should have a small slot shaped cut out about 1/2 the way across the top of the intake. I can't find the instructions on how to google within this site but there are pictures that show the differences. The exhaust port includes a "ramped" area inside the cylinder that leads to the "Q"port. Ron

I don't think that the notch in the top of the intake port would make much difference. If it were on the bottom of the intake that might make a difference.

 

[Nardoo]

Sp-105

Hello everyone,
I do not have many Macs but recently aquired this SP 105 that I had fun getting going. I love the way they are laid out to make them easy to work on. Tuning the carb was a learning experience - why did McCulloch use a carb with no high speed adjustment? But it idles like a baby and has the most beautiful sound.
In the cut it compares very favourably to my 070, a good feat.
I think I am starting to like these yellow beasts.

Al

 

[rwoods]

I don't think that the notch in the top of the intake port would make much difference. If it were on the bottom of the intake that might make a difference.

Can't say as this is beyond me why it was cast this way. Ron

 

[rwoods]

Hello everyone,
I do not have many Macs but recently aquired this SP 105 that I had fun getting going. I love the way they are laid out to make them easy to work on. Tuning the carb was a learning experience - why did McCulloch use a carb with no high speed adjustment? But it idles like a baby and has the most beautiful sound.
In the cut it compares very favourably to my 070, a good feat.
I think I am starting to like these yellow beasts.

Al

Nice saw. If you're like me, you'll love it and start looking for more. I'm told the single jet was to cut back on warranty problems and bad fuel issues; scout out a carb from an older model 125 and you'll have more flexibility. Ron

 

[Dennis Gauge]

Can't say as this is beyond me why it was cast this way. Ron

I think the slot is supposed to replace the decompression valve and make the saw easier to start.

 

[leeha]

Nardoo, Thats a sweet 105 you have.
Nice looking saw. I bet you are hooked
on yellow now. No turning back.



Lee

 

[Nardoo]

These yellow saws do kind of grow on you. There are loads of them around here but mostly are old farm saws and have had a very hard life. I will keep my eye out for some bigger ones.

Al.

 

[Warped5]

Hello everyone,
I do not have many Macs but recently aquired this SP 105 that I had fun getting going. I love the way they are laid out to make them easy to work on. Tuning the carb was a learning experience - why did McCulloch use a carb with no high speed adjustment? But it idles like a baby and has the most beautiful sound.
In the cut it compares very favourably to my 070, a good feat.
I think I am starting to like these yellow beasts.

Hi Al -
You're hooked! Nice saw! I'm not REAL sure, but you may be able to use what's called a '10-10 conversion kit' for it, that will have a more conventional carb in it. $35 US on eBay ..... maybe StinkBait will see this and verify the info. He's the one that gave me the heads up on the kit for my SP81 project that is dragging on and on and on .... :msp_mellow:

 

[hoss]

Thanks for all the info and pic Ron. That is exactly what I was lookin for. Definately have to add an 800 to the stable.

 

[hoss]

I think the slot is supposed to replace the decompression valve and make the saw easier to start.

After reading Marks service bulliten that is what I thought too.

 

[rwoods]

I think the slot is supposed to replace the decompression valve and make the saw easier to start.

So you think the intake slot and the Q port on the exhaust were designed to work together to lower the starting compression??? I thought it was just the Q port with the intake slot designed to get a better intake charge. I know almost zil about piston porting, ports and timing. I'll look at the heights later today. Ron

 

[rwoods]

I see no way that the slot in the intake port can lower starting compression; the top of the slot is lower than the bottom of the exhaust port. Also the intake must have a vaccum draw not a pressure discharge. Am I missing something here? Thanks, Ron

 

[ChainsawmanXX]

Hey Brian, ends up I had one but it wasnt in very good shape. Sorry!

 

[Eccentric]

It's so so wrong, and prolly should be more in the poulan thread than this one, but I am trying to get my ported wild thing fix by going with a mac-labelled wild thing/4218/poulan pro etc. Let me know if you guys come across one for cheap...

Ugh. At least it's not green and purple....:jester:

Is $25 bucks normal for a 10-10 air filter (the domed one)? Seems like a lot.

McCulloch Chain Saw AIR FILTER fits 10-10,PM 55,60,700 | eBay
yea that does seem alittle steep lol

That's the wrong one it's too flat. The one I need is the domed up one, cheapest I see is $25!

I saw one of the domed early 10-10 filters on feebay for $19 or so. I've got one of those saws, but I doubt I'll run it enough to need a second filter. What's on there is in good shape. They are a lot more pricey than the flat later filters.

I don't think that the notch in the top of the intake port would make much difference. If it were on the bottom of the intake that might make a difference.

Can't say as this is beyond me why it was cast this way. Ron

I think the slot is supposed to replace the decompression valve and make the saw easier to start.

Yep. The pointed exhaust port top on the PM800 is meant to bleed down compression at cranking speeds, negating the need for a compression release. Some large displacement 2-stroke dirt bikes (such as a Kawasaki KX500) have had similar port cuts for the same reason. Older 2-stroke large displacement bikes (like my 1975 Yamaha MX400 project) have manual compression releases. I agree with Ron in that I don't believe the intake port differences are there for compression release purposes.

 

[briantutt]

Hey Brian, ends up I had one but it wasnt in very good shape. Sorry!

I'm sure I find one by the time I need it. Thanks for checking. Saws get fixed very slowly around this place.

 

[briantutt]

10-10 Automatic

Are the flywheel nut threads right or left hand on a 10-10 automatic?

 

[Eccentric]

Are the flywheel nut threads right or left hand on a 10-10 automatic?

RH Thread.