McCulloch Chain Saws

[heimannm]

The 3-25 has a very unique fuel/carburetion system, get an IPL and move slowly.

I have a few of the old double hook diapraghms if you need one but I can't give them away...

Mark

 

[ChainLightning]

The 3-25 has a very unique fuel/carburetion system, get an IPL and move slowly.

I have a few of the old double hook diapraghms if you need one but I can't give them away...

Mark

My plan is to save it for a project this winter when it's not deer season. I am not going to plan on replacing anything. If I find a major problem that I can not fix myself without other parts, my plans are just to put it back together and set it on the shelf for a conversation piece. But if I can get it running, that would be cool! I checked for spark today and had none. So I know that right there is a good chunk of a tear down right there to the points.
I asked the guy that I bought it from the story behind it and he told me that 30 years ago he bought it just so he could take it with him to get into tractor shows and other engine shows for free but it does turn and have good compression. Throttle is froze and no spark so thats gonna be a good project. Thanks for the offers on those diaphragms. If this saw had sentimental value then I would probably consider. Anyways I think it looks cool and it is a great piece of American logging history.

 

[heimannm]

Points are external on the 3-25, there is a cover on the top/front of the saw. Very easy to get to.

Mark

 

[ChainLightning]

Points are external on the 3-25, there is a cover on the top/front of the saw. Very easy to get to.

Mark

Ok I was wondering what that was for. Thanks

 

[promac850]

Tried adjusting the throttle stop, and it did improve a little bit. However, it still is slower than it should be.

If it wasn't getting enough fuel it would, it'd be screaming, right? It doesn't scream at all, in the cut or out of the cut. It clears up from the out of cut burble when the bar is buried.

Anyone else think that since a 36" (according to a few folks here) is the max recommended bar length, then 24" with an 8 pin may be slowing it down so much that it's not in the good power band? The ports are a little different (and higher due to the teardrop) than stock... maybe less low end torque and more upper end power resulted?


So, what I am going to do is swap a 7 pin clutch drum on, and also check the points again to make sure that hasn't changed. It is snatching the recoil handle a little more now than before, so there may be a timing issue there.


Going to have to fix the clutch cover/recoil assembly, again. It is getting beat to hell on this thing and has developed not one, but two cracks. Thankfully not in the repair area I stop drilled. The one without the hole stop drilled at the end, however...

Yes, I do pull the recoil cord out before shutting it down... it's a must with these big Macs. Still, those recoil snatch backs on attempt to get it started are hard on the recoil assembly.


It also needed to be retuned for it to idle and run. (it has gotten a lot cooler out since the last time I ran it)


But then again regarding bar lengths... IIRC, RandyMac claims to have run a 36" bar with an 8 pin on a PM850 in soft wood. So should the 790 be able to pull a 24" with an 8 pin? Or is the difference between 3/8" (.375") and .404" really enough to require a lot more torque and power to run the latter, thus require a 7 pin?

 

[RandyMac]

Oh bar maid!

36" to 42" is optimal for the 6 cube class, wouldn't go less than 30".
Whether an 8 pin will help you, depends on your chain filing ability.

 

[OREGONLOGGER]

I switched over to 3/8 and just a 7 pin on my Super 797 instead of the .404 and lets just say I'll be racing with 3/8 next year. As far as torque on your 790 with 3/8 and 8 pin....same torque and faster I say, nice to have a roller or an old Speed Mac bar for that 8 pin app. Let us know how that 8 pin works for you good info indeed

Cascade Saw

 

[ChainLightning]

Oh bar maid!

36" to 42" is optimal for the 6 cube class, wouldn't go less than 30".
Whether an 8 pin will help you, depends on your chain filing ability.

just slap a 14in on it and call it good

 

[joeymt33]

I'm hundreds of miles from my shop and saws but I must be in a good place. With a name like "Macland", I thought I was in Dike Iowa.

 

[leeha]

Throw the carb in the trash and make it run. :hmm3grin2orange:





Lee

 

[8433jeff]

Oh bar maid!

36" to 42" is optimal for the 6 cube class, wouldn't go less than 30".
Whether an 8 pin will help you, depends on your chain filing ability.

Now I have jabbed you in the past about being a greenhorn, but this isn't about that, so adjust the tude accordingly.

I believe in the pirates book of logging it also says something about the ratio betwixt operator skill vs. bar length (more experience, more bar) and I would agree with my barnacle encrusted ship swapping friends of the sea about the chain condition.

Get it to run well at a 7 pin, then experiment.

The teardrop comment has me wondering if that is a factory thing or a floor sweeper mod, not that modding is a bad thing. Its always easier to mod a runner than a fixer upper, as you have a baseline.

 

[promac850]

Oh bar maid!

36" to 42" is optimal for the 6 cube class, wouldn't go less than 30".
Whether an 8 pin will help you, depends on your chain filing ability.

Hmm... is that a promotion or another demotion? Anyhow, it sounds like another new user title...

As for the chain, it is fresh off of the grinder from a local shop. He knows what he's doing. However, I found the gullets to need some clean out, so I did that today. It seems to have made a difference, mainly with chip clearing.

I'll check the depth gauges (rakers) and see where they are at. It's possible that they may be a tad low. I'll report on that tomorrow.

8433 Jeff,

As for the teardropped ports, that was a mod I did. I really don't have much patience for pulling engines down and putting them back together to get a good mod (at least on these Macs, they require complete disassembly, unlike the 80's and 90's green machines or numerous other newer and some older saws with vertical or horizontal cylinders that come off of the crankcase)

What I should've done is been a lot more scientific in my methods, and used a ring to mark the highest spot line and grind to that rather than eyeball it. I think I may have teardropped them a little too high. Maybe the muffler is a little too restrictive? I imagine that if the muffler is holding back too much exhaust gas, it would reduce the effectiveness of slightly raised transfers since the benefit or more air/fuel is blocked by said exhaust restriction.

We'll find out for sure sometime tomorrow after I mow the inside yard and change to the 7 pin, and maybe after repairing the recoil cover and going through the carb again. I never did pull that 1" welsh plug to clean out under there. Keep reading around here that it tends to make a big difference in performance...

Anyone think I just need to get an ultrasonic cleaner and run it through that a few times? I do have money to spare on something like that as of right now...

 

[promac850]

Throw the carb in the trash and make it run. :hmm3grin2orange:





Lee

I'll throw it away if you give me 30 bucks for the wasting of a new SCS carb kit...

 

[Steve NW WI]

Am I a bad person?

From this thread: http://www.arboristsite.com/firewood-heating-wood-burning-equipment/206038.htm

First guy to laugh at the MonkeyMac gets two of his non running cousins sent to him!

Send me a broken cousin over here, Steve!

You asked for it. Prepare for a lesson in patience and temper management. We will expect to see a repair thread with pics of course.

PM me your address, and I'll wander on down to the shed and see if I can find one that looks like it might run without too terribly much grief, and I'll include a box of parts loosely resembling a saw as well.

The boys in the McCulloch chainsaws thread in the Chainsaw Stickies will offer advice, encouragement, and spare pieces if needed, in return for the humor you provide them.

Tell ya what, you get that little critter running well, and not only will I stop giving you grief about constantly asking for pics, but I might be able to find a "real" project saw for ya to wrench on.

 

[Eccentric]

Am I a bad person?

From this thread: http://www.arboristsite.com/firewood-heating-wood-burning-equipment/206038.htm

Nope. He asked for it.....

 

[psuiewalsh]

Everyone should have a mini mac attack.

 

[diggers_dad]

Mac 300 parts

I have a Mac 300 in good condition, missing the carb, linkages, etc... from the carb box. Otherwise the saw seems complete with b/c, bar scabbard, caps, etc. It shows 130 psi on my gauge and has good spark. If you need parts from this saw or all of it, shoot me a pm. I'm only into it for $20 bucks, so a few bucks over shipping or interesting trade material will be plenty.

You can also email me for a faster response. [email protected]

edit: If I posted in the wrong forum I can move it to the Swap Meet thread, I just thought this was the right place for a Mac deal.

 

[diggers_dad]

I have a Mac 300 in good condition, missing the carb, linkages, etc... from the carb box. Otherwise the saw seems complete with b/c, bar scabbard, caps, etc. It shows 130 psi on my gauge and has good spark. If you need parts from this saw or all of it, shoot me a pm. I'm only into it for $20 bucks, so a few bucks over shipping or interesting trade material will be plenty.

You can also email me for a faster response. [email protected]

edit: If I posted in the wrong forum I can move it to the Swap Meet thread, I just thought this was the right place for a Mac deal.

OK, the Mac is spoken for. I thought it might take a couple of days. I had no idea?!?!!? You guys were on that like dogs on a three legged cat!

 

[heimannm]

I found another old McCulloch dealer tonight, spent 2-1/2 hours looking through all his treasure of saws & parts, Wheel Horse lawn tractors, you name it. One of these days I'll post up some photo's of this weeks CADDITIONS.

Mark

 

[rheima]

Cadadditions

Wheel Horse? Any complete old tractors?

Ray