McCulloch Chain Saws

[heimannm]

The cylinder on the mower is reminscent of the drone engine or the engines McCulloch was building for Reed Prentice before they went into chainsaws on their own.

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Dave86 - if you happen upon a stash of carburetors for the BP-1 saws I am in need of three.

I spent most of the day yesterday trying various things on these two, one is my runner from years ago and the other was put together from a large parts lot I picked up a few years ago. Both saws will run with the one good carburetor that I have, the other carburetor will seem to work for a while then the saw floods out. Either the material they used for the carburetors was low quality, or the carburetors that I have were stored in less than ideal conditions as they all seem to leak along the seams even with new gaskets and diaphragms. I can live with a little bit of seepage but fuel running out does not work.

At one point I even tried to use the carburetor from a 170 welder which looks the same externally, but when I tried to swap the throttle shafts (the arrangement on the welder is different than the saw) I discovered the welder carburtor has a much larger throttle bore.

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One reliable runner, one almost runner, and one really bad carburetor.

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I found it interesting that on several of the McCulloch/MAC carburetors (flat back and the BP-1) they opted for a fine screen rather than a more conventional high speed check valve. I know for some of the flat back models McCulloch offered a coversion kit to add a check ball in place of a sintered metal screen.

Mark

Brian Genrich sent me some additional gasket/diaphragm sets after the first round of testing. The updated parts worked much better, we were even able to get the second saw running and cutting today. It still has some issues as the primer is quite sticky, and it will tend to flood out if it sets and idles for too long, or comes down too quickly after a hard run. None the less, I now have two runners and pretty happy about it.



Mark

 

[bob kern]

Brian Genrich sent me some additional gasket/diaphragm sets after the first round of testing. The updated parts worked much better, we were even able to get the second saw running and cutting today. It still has some issues as the primer is quite sticky, and it will tend to flood out if it sets and idles for too long, or comes down too quickly after a hard run. None the less, I now have two runners and pretty happy about it.

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Mark

That's great Mark congrats.
By the way, I may be the owners of a poulan 5400 Friday. When you compared them to an 850 Mac it got me thinking. Then one came up for sale!

 

[Jethro 2t sniffer]

Brian Genrich sent me some additional gasket/diaphragm sets after the first round of testing. The updated parts worked much better, we were even able to get the second saw running and cutting today. It still has some issues as the primer is quite sticky, and it will tend to flood out if it sets and idles for too long, or comes down too quickly after a hard run. None the less, I now have two runners and pretty happy about it.

View attachment 1083513

Mark

What's the grunt like on those Mark?

 

[heimannm]

Being only 44cc, they will cut pretty fast for a gear drive but you have to hold them in the RPM range to work well.

Mark

 

[Jeffrey F.]

Brian Genrich sent me some additional gasket/diaphragm sets after the first round of testing. The updated parts worked much better, we were even able to get the second saw running and cutting today. It still has some issues as the primer is quite sticky, and it will tend to flood out if it sets and idles for too long, or comes down too quickly after a hard run. None the less, I now have two runners and pretty happy about it.

View attachment 1083513

Mark

What do you feel is the difference as to working better ?

 

[heimannm]

The other gaskets were too hard and so did not seal properly. The carburetor would leak internally and externally so it was impossible to control the fuel/air mixture into the saw.

With the proper gasket material and the carburetor sealed up, control was possible and so the saw could now run.

Mark

 

[Jeffrey F.]

The other gaskets were too hard and so did not seal properly. The carburetor would leak internally and externally so it was impossible to control the fuel/air mixture into the saw.

With the proper gasket material and the carburetor sealed up, control was possible and so the saw could now run.

Mark

So the 3D printed ones, was it the filament material, I’m assuming, or printed wrong. Just curious.

 

[j-jock]

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About 10 years ago, I bought a new McCulloch straight shaft trimmer from Walmart. It was a wonderful machine until the coil died. I could not find a replacement for it anywhere, so I moved on. I was really pissed that the machine was in beautiful condition but unusable.
Bob

 

[heimannm]

So the 3D printed ones, was it the filament material, I’m assuming, or printed wrong. Just curious.

The gaskets were cut from paper, but evidently this particular paper was impregnated with resin of some sort making it too hard and not resiliant at all. The newer ones were more conventional gasket stock and could conform to the minor irregularities in the surfaces of the carburetor.

Mark

 

[bob kern]

Bringing it home!

 

[Maintenance supervisor]

Bringing it home!View attachment 1083992

I thought you were bigger?

 

[edju1958]

Is there an "easy way" to put a new oil line in a 10-10?

 

[heimannm]

Still working on getting saws cleaned up in preparation for moving them in to the display. This 1-70 was pretty bad...











Mark

 

[bob kern]

I thought you were bigger?

Lol you are the second one to say that.

 

[vinnywv]

Not for me either ed. They are pretty difficult to do. Id rather work on a mini mac. Lol

 

[Yukon Stihl]

Bringing it home!View attachment 1083992

Nice Burb

 

[bob kern]

Nice Burb

Ya we like it. '92 with 222,000 but still going strong.

 

[edju1958]

I picked up 2 more saws,not that I need 'em,just like working on 'em.I got a PM605 for $40 & a Timber Bear for $20.50.As for ease to work on,they're comparable to the 10 series IMO.About the most involved thing to do is replace the oil line in the tank.As one member here put it a few yrs.back "McCulloch took an oil line & built a saw around it",Lol.

On another note,I stripped down a Super 10-10 yesterday & proceeded to swap everything onto a different short block.My 1st order of business was to swap the oil line over- easier said than done.I ruined the original oil line,but found another one.With a lot of persistence & cussing I finally got it into place & the oil pumps installed.Kinda tough to do with only 1 1/2 hands.If my P.T.saw what I was doing she'd probably have a stroke,Lol.

 

[bob kern]

Nice Burb

As of 2 hrs ago, I may be selling it. Found a 98 with 60,000 less miles that mama likes. She does the cookin so if she likes it here ina few I imagine we'll be driving it home.

 

[bob kern]

As of 2 hrs ago, I may be selling it. Found a 98 with 60,000 less miles that mama likes. She does the cookin so if she likes it here ina few I imagine we'll be driving it home.

Well she likes it