Mac 640 From Brian

[GASoline71]

Wow Brian... this thing looks like it doesn't have a lot of use on it... I was not expecting it to be in this good of shape. Thanks a ton! It's gonna be one of the first projects after movin' in to the new digs...

The bar should be here tomorrow...

Just figured I would show it off here...

Gary

 

[MasterBlaster]

I've ran that sucker, nice.

 

[GASoline71]

Well... When I get this thing runnin'... I won't need to go to the gym anymore... I just need to pack this thing around for awhile.

It's heavier than my Homelite 770G... and the Homie has 15 more CC's on this one.

Gary

 

[SkwerI]

I thought the same thing at first also, Gary. But upon closer inspection it's seen a bit more use than you might think. Somebody attempted to get it running a few years back and they cleaned it up pretty good, so that might be why it looks so good.

I'm glad that you like it and that it found a good home. Looking forward to a very detailed thread with lots of pictures documenting the entire restoration process.

 

[GASoline71]

Kinda like my truck thread?

The sprocket is very worn. Don't get me wrong... I meant to say that it's seen it's share of wood. But for a 35 year old saw... it's in pretty decent shape.

Gary

 

[stehansen]

I'm looking forward to this thread also.

 

[Al Smith]

Get it running and I'll send you a sprocket if you can't find one .

 

[Al Smith]

Say I just looked up the IPL of that thing and it lists a .404 sprocket as an option . This is one of the very few Mac gear drives to do so as most were 1/2" .

 

[gf beranek]

Looks painful to operate, but no doubt a real solid piece of aluminum and iron.

 

[woodworkingboy]

Is there any anti-vibration built into that saw?

 

[Al Smith]

Yes it's heavy and doesn't shake too much .

 

[GASoline71]

Your arms provide the "AV"...

Al... this one is set up with .404... Acres site shows the same thing.

Gary

 

[Al Smith]

I wasn't even knowledgable they even offered it in .404 until I looked at the IPL of the 640,you lucked out . Unfortunately one of those I don't have .

Offer is still good though,I can carve one out on the mill when I get a chance . It will take me some deciphering to figure out the pitch diameter though .

When I carved out a 1/2" a few years back I just mounted the old one and a blank on a common arbor that way I didn't have much figuring to do . Simple things for simple minds .

Oh does that old monster have a Tilley HL or a flat back ?

 

[GASoline71]

I think it is a flatback... I'll have to look again. The outer bar mount has a crack... from what I have gathered it was a fairly common for this to happen on this model.

The bar came today... holy shit... it's one of the fairly rare bars with the big "Mc" stamped on the belly...



Gary

 

[SkwerI]

I figured you might like that.

 

[Al Smith]

I'll have to get the camera out some time and submit some pics of Mac bars .I've got some really ornate ones . Some have geese,some have McCulloch in long ornate lettering.Many are galvanized . One doesn't have an oil hole and I have no idea how the bar was lubed on that one .

 

[GASoline71]

Hey Al... any way I can get a copy of that 640 IPL?

Gary

 

[Al Smith]

Of course you can .I don't know if I have that one copied or not .My damned flatbed is busted and I haven't replaced it but somewhere I have a disc in PDF if I can find it . PM me an E-mail and I'll get it as soon as I can .

 

[GASoline71]

Thanks for the IPL Al... That will come in handy. I'm gonna try to do a little tinkering on it this weekend. But it depends on how much traveling I have to do with my daughters soccer team. We have a tourney this weekend.

Those flatback carbs... are thoes a McCulloch carb? Or did someone like Tilly or Walbro make them for Mac?

Also... you wouldn't by chance have an IPL for a 797 would you? I have one of those monsters landin' on my doorstep today...

Gary

 

[Al Smith]

Yep on the 797 ,fact is I have about any ever made but some are on micro fitche and I have no way to copy them .

The flat back is a Walbro and a chore to find parts for and then at 50 bucks a pop to boot if you do find a kit .

If the innards are stiff try soaking them in brake fluid for a couple of weeks . You might get lucky though,stranger things have happened .

I'll fire you off the IPL when I get a chance .

 

[GASoline71]

Cool thanks... I appreciate the help.

I was lookin' at the carb last night, and noticed that someone, at one time, removed it and reinstalled it with the star washers between the carb and intake... I can get a .050 feeler guage in there...massive air leak.

I'm gonna pull the muffler tonight and check out the cylinder.

Gary

 

[Reddog]

Well that air leak is one way to make sure it dosen't run after working on it.

 

[Al Smith]

You would be totally amazed at the amount of people that attempt to work on those old Macs but screw them up . They have got to be the easiest saws ever made to turn a wrench on .With the exception of those infernal Mini Macs . Those could make a preacher cuss .:what:

 

[GASoline71]

I just checked the spark... massive blue arc. The screws holding on the cover to get to the plug have never had a screwdriver in them. Not a single mark on them.

I need to move the star washers out from between the carb and the manifold and install a new fuel line. Prolly be runnin' soon. Pulled muffler and nary a blemish on the exhaust side of the piston. The bore is nice and shiny too...

Hey Al... the primer pump lever is stuck. Won't pump down. Don't wanna reef on it and bend or break anything... any idears?

Gary

 

[woodworkingboy]

I don't know what those old macs rev to, but the star washers might be
an attempt to jack them up, by someone desperate.