McCulloch Chain Saws

[briantutt]

Yes, the saw is here!!! Thread is posted.

Please link to it!

 

[betterbuilt]

P.S. Looking at the photos again, that saw appears to be in very good shape, let me know if you don't want it, I may be interested. The early McCulloch saws of that family seemd to be very popular in your part of the country, I got a 4 saw package as couple of years ago but those saws had really been used.

Mark

I just noticed you edit. I'll probably pick it up and I'll let you know If I decide not to keep it.

If the piston is scored, what should I offer?

 

[promac850]

Please link to it!

http://www.arboristsite.com/chainsaw/163638.htm

Silly me. :silly: I forgot to post a link. :silly:

 

[Brian13]

Funny story I got a saw in the mail the other day, and it was very obvious it was not the one I bid on. It was clearly a 10-10, well apparently it was sent elsewhere to another member here LOL. It seems to be in rough condition, but has a 2" bore. So it sounds like I will have a rough condition 70cc saw to redo in another week or so.

 

[stinkbait]

Several guys ran my SP125C today at the TN GTG. It didn't seem to be reving as fast as I thought it should. I believe this was also noticed by some more experienced than me but who were too polite to just come out and say it. I was asked about whether it had a fixed jet. Not having tinkered with the carb I didn't know so we checked and it is a fixed jet. I was told that this was a manufacturer's safety device to prevent tinkers like me from burning up saws. Long intro to my question. What else, if anything, could be holding this Mac back? Is a fully adjustable carb worth the expense and trouble? This is the quickest starting MAC I have ever owned. So I don't want to mess with a good thing just to get a little more speed but like most I want all the speed I can get. Ron

My SP125 had the fixed jet, but I put an adjustable carb off of a CP125 on it. It made a noticable difference in power. For one thing, if you campare the fixed jet tillotson to the adjustable walbro, you can see that the walbro has a noticeably bigger venturi. I have my SP125 tuned to 10,500, and it four-strokes a plenty.

I got to thinking about this again today Ron. I did a little looking and found that the adjustable sdc has a venturi diameter of 0.75" and the tillotson fixed jet has a venturi diameter of 0.687". That's a pretty big difference when it comes to venturi size.

 

[heimannm]

Quite a few large displacement saws utilize carburetors with .687 venturi/.812 throttle bore.

Bigger bore carburetor will only improve performance if

1) current carburetor is limiting air/fuel flow into the engine and

2) there is sufficient air flow through the larger venturi to still create the pressure drop across the venturi required to flow a sufficient quantity of fuel

You could put Neals double pumper Holly (sorry, that was another thread) on a Wild Thing, but that is not necessarily going to yield a big improvement in performance.

Mark

 

[igpoe]

Quite a few large displacement saws utilize carburetors with .687 venturi/.812 throttle bore.

Bigger bore carburetor will only improve performance if

1) current carburetor is limiting air/fuel flow into the engine and

2) there is sufficient air flow through the larger venturi to still create the pressure drop across the venturi required to flow a sufficient quantity of fuel

You could put Neals double pumper Holly (sorry, that was another thread) on a Wild Thing, but that is not necessarily going to yield a big improvement in performance.

Mark

Mark,
Have you ever run a 125 with a SDC 20 on it?
Dean

 

[heimannm]

SDC 20 anyone?

No, send me one and I'll set one of mine up with the SDC, leave the fixed jet on the other, and see how they compare.

Mark

 

[igpoe]

No, send me one and I'll set one of mine up with the SDC, leave the fixed jet on the other, and see how they compare.

Mark

You seem to be suggesting that I remove my $60 carb and send it to you.
I'm satisfied with the performance of my saw and am not really curious about yours. If you would need proof of the added performance perhaps you should obtain an SDC 20 the same way we did. If you don't see the difference it will be because your saw will not achieve the needed pressure drop you refered to in your post. I don't have a carb to spare,sorry.
Igpoe

 

[8433jeff]

Igpoe, I think he'd send it back after the test. He might even deliver it. But i might not let it out of my sight either.

 

[heimannm]

Well VA is not in the normal circles I run but I've been after the guys out there to schedule a trip again...

I'll look around to see what I can find, what saw(s) would have used the SDC 20 as original kit as a place to start looking?

Mark

 

[hoss]

Have had some nice luck with my Mac's latley. I just finished a rebuild on a pair of 795's, cleaned and swapped for a tillotson on a 550, just got a very nice 890 and swapped on a .404 gear, built my third PM1000 and recieved a near mint 1-60 gear drive that already runs great has a .404 gear and is spotless. It has been a good Mac month. Do any of you guys have one of the Mac gear drive style bucking spikes you would be willing to trade or sell? I will hopefully have some time for some videos in the near future.

 

[rwoods]

Sdc 20

Sure didn't mean to start something with my questions. If someone has a reasonable source for a SDC 20, I'll buy it send it to Mark for testing in his leisure (if he wants to test it) and when he's done he can send it back to me. I may just buy a tach as my concern could just be a mis-perception caused by the passage of forty years from when I last heard my Dad's MAC or just 40 years of use/damage to my ears since then. Ron

 

[heimannm]

Hoss - try Bob Johnson for the spike, he had one last time I checked.

Igpoe - I see the SDC 18, 19, and 20 are all listed with .750 venturi and .812 throttle bore and used on a number of different McCulloch saws. I might actually have one on a saw in the shop. This will require some investigation...

Mark

 

[stinkbait]

Hoss - try Bob Johnson for the spike, he had one last time I checked.

Igpoe - I see the SDC 18, 19, and 20 are all listed with .750 venturi and .812 throttle bore and used on a number of different McCulloch saws. I might actually have one on a saw in the shop. This will require some investigation...

Mark

The 18 and 19 would work, but you would have to drill the pump side cover to install a nipple for the impulse line to attach to. That wouldn't be too hard since there is already a raised spot cast on the back of the pump cover where you would drill.

 

[RandyMac]

Hoss, you looking for a manly set of spikes or the standard ones?

 

[heimannm]

Thank Mitchell, after thinking about last night it I realized the 10 Series have the impulse port integral in the mounting flange.

I will have a look at the saws on the shelf tomorrow to see if any have the SDC 18, 19, or 20. Before I modifiy the carburetor, does anyone know of another application where the caburetor is already set up for a remote impulse line? I can buy a new/different carburetor if someone will point me in the right direction.

Thanks,

Mark

 

[rwoods]

Welcome back, RandyMac. Ron

 

[djones]

The S44A is supposed to be a strong saw and a high reving saw for its time. I have heard nothing but good about them. I am currently looking for an oversized piston for one I have.

Brian, you PM box is full. I did contact the person in question. PM me your address and I'll get your saw to you, plus let me know about the spare parts.

 

[igpoe]

Cp125

Thank Mitchell, after thinking about last night it I realized the 10 Series have the impulse port integral in the mounting flange.

I will have a look at the saws on the shelf tomorrow to see if any have the SDC 18, 19, or 20. Before I modifiy the carburetor, does anyone know of another application where the caburetor is already set up for a remote impulse line? I can buy a new/different carburetor if someone will point me in the right direction.

Thanks,

Mark

Mark, as I understand it, the CP 125 had an adjustable carb. Have you got one of those? I don't know if that saw had the seperate impulse or not. I got my carb from Bob whatshisname in New York and he told me he had to get it from somewhere out west. According to Bob, I got the last one on the planet..........................you know how that goes.
Dean