McCulloch Chain Saws

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Too much small talk for RandyMac :cool2: Ron
 
Anyone know exactly which gasket material I need to make gaskets for the 790 engine gaskets? I want to get it together asap.

Ordering parts from the Mac parts master doesn't work well since I simply have a hard time hearing over the phone.

As for what other parts I need, it's pretty much only that cosmetic piece, the grille on the air filter cover, and an air filter.

I have one more question... is the governor that they installed on these big Macs for the idle, or do they control top end rpm as well? I hope it doesn't choke down the latter, as this six cuber is ported... if it's the former, I'll see if I can get a flatback to work right. If it's the former, a Tilly HL will be installed.

Bump with minor correction... if no one answers, I might not have this big Mac barking for us to talk about in the next few days.

Do I use cork/rubber gasket material, the cardboardy stuff, or something else? And where is the best place to get it?
 
Bump with minor correction... if no one answers, I might not have this big Mac barking for us to talk about in the next few days.

Do I use cork/rubber gasket material, the cardboardy stuff, or something else? And where is the best place to get it?

You should be able to buy the gaskets for cheap money.
But if you insist on making them i use the Napa stuff.
It's the brown or tan colored paper. They have it in a
couple different sizes. I mostly use the thin stuff.



Lee
 
Slow but progress

I spent some time tonight putting anti-vibe on my MAC screws so they would be cured and ready to go. The hex screws are for the 125C & 101B. The allen head screws are for the PM800s. That little bottle of anti-vibe is almost $40.00!!!

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Yes, Aaron, that is a small bag of those impossible-to-find recoil cover screws. I gave up looking for a supply so I ordered the newer allen head version. What I got was one allen head and the rest were slotted.


I grew impatient with our head waiter, so I made my own heavy duty tension adjusters. The pair at the left are from a Sears 3.7 Ranger (I need to make up some proper length SAE allen head screws); the next two sets were made using the metric nuts from MAC 380s (two styles- thin and thick); and the last is from a Husky also metric (nut is narrower than the cover slot but it works). The metric allen head is close enough to SAE that I can use a SAE wrench. Sorry for the blurry picture.

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Ron
 
I spent some time tonight putting anti-vibe on my MAC screws so they would be cured and ready to go. The hex screws are for the 125C & 101B. The allen head screws are for the PM800s. That little bottle of anti-vibe is almost $40.00!!!

Yes, Aaron, that is a small bag of those impossible-to-find recoil cover screws. I gave up looking for a supply so I ordered the newer allen head version. What I got was one allen head and the rest were slotted.
Ron

Ron, where did you order the screws from? McMaster-Carr?

The anti-vibe, is that stuff the Nylok brand stuff? How good does it work?

bob
 
Lee, where can Kyle buy the gaskets without using the telephone? Or who can I call and order them for him. Thanks, Ron

Here's an important gasket I recently bought for Randy's 790. Crankcase stuffer gasket. The oil tank gasket is also on feebay, but I just used Threebond 1194 (actually Hondabond-4.....same thing) for that. Both of those gaskets are thin brown card stock type material. The intake/insulator gasket is much thicker material, but also brown card stock.

MCCULLOCH CHAINSAW GASKET COVER 65654 SUPER PRO 125 PM 105 SUPER 550 | eBay

Kyle can of course order the ebay gaskets using the computer rather than the phone. Otherwise, you'd have to call Bob Johnson or one of the Kart guys to order the gaskets for him.
 
Ron, apologies for not getting around to those adjustment screws yet. I want to get the 790 engine together at can be safely stored into a box or assembled into the complete saw before grinding away on metal in the bench vise. (I know, no excuse for slacking off and doing other stuff...)

I already have a good idea of how to mass produce those little adjustment tabs out of 1/4" plate steel. I'll be sure to get tons of them ground up, drilled, and tapped once it is all set up.

Then all that will be needed is the screws and nuts. Washers to reduce wear on the clutch cover are a good idea as well.

I will be digging around on feebay to find some gaskets.

Where do I acquire the welch plugs for the lower transfer access ports? IIRC, someone said Napa would have them. Is my memory correct?


p.s. I worked form 7:35 to 3:45 today, was at work last week Wed. - Friday as well. Probably going to have to work this Tuesday as well. Firewood contract... a national park here needs lots of bundles done.
 
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Lee, thanks for the information relay. I don't know enough about the big MACs to know what interchanges and what doesn't.

Aaron I mean Bob, big MAC screws came from eBay seller of kart parts (Vincent - Carburetor Parts, Screws items in Vintage Vixsin store on eBay!) He made me a bulk deal. The recoil cover screws and flywheel cover screws came from Lawnmower parts. Parts for Generators, Pressure Washers, Power Tools, Chainsaws, Trimmers, Leaf Blowers, Snow Blowers, ATVs. The non-MAC screws came from Fastenal as did the thread lock (Vibra-Tite made by N.D. Industries Vibra-Tite | High Quality Threadlockers, Adhesives, Sealants & More.). No one locally carries the green Loctite and all the other colors are for 1/4" and up fasteners. Fastenal gave me a 1/4 of a bottle of the vibra-tite to try. I haven't had any screws fall out yet even though I didn't let them cure (label was too small for my old eyes). I am following the directions this go around.

Kyle, I'm not sure that 1/4" mild steel will hold up to the mighty MAC. What is the factory nut thickness? I am after two things with the nut - a nut strong enough not to bend and wide enough to keep the screw from bending. Maybe the grade 8 screws I am using will solve the latter, only time will tell. I am using allen head screws not only for the strength but also so I can use a ball head wrench to gain knuckle clearance. Another flaw in the factory nut IMO is the tip is too short. If it were longer (like a Husky) it would be easier to line up with the bar and you would be less likely to tighten the cover with a misaligned adjuster as many do as evidenced by all the busted covers you see. Of course you don't want to get the tip too long or you'll bust you oil tank.

Ron
 
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Hate for some non-MAC fanatic to grab it so I'll post it here instead of the eBay thread - don't miss the $1000 MAC bar with free shipping. :msp_wink: Vintage 78" Chainsaw Bar!!! Stihl, Homelite, Mcculloch, Pioneer, Husky, Etc!!!! | eBay Ron

Looking at the tail end, I'd say that's a large frame Homelite bar. A 78" (probably more like 72-73" cut length) General RN in that mount is fantastic and hard to find.........................but a GRAND for a rusty, used bar?????????:dizzy:
 
Looking at the tail end, I'd say that's a large frame Homelite bar. A 78" (probably more like 72-73" cut length) General RN in that mount is fantastic and hard to find.........................but a GRAND for a rusty, used bar?????????:dizzy:

That could easily be a Poulan bar...think I have one like it, only shorter, on my Dayton.
 
Looking at the tail end, I'd say that's a large frame Homelite bar. A 78" (probably more like 72-73" cut length) General RN in that mount is fantastic and hard to find.........................but a GRAND for a rusty, used bar?????????:dizzy:

That would go nice on my 995G but where would I find that much 1/2 inch pitch chain?
 
Would someone here just sent me some cash and authorize me to spend it so I can satisfy CAD urgings vicariously - I just missed a $99.00 clean looking PM700 while trying to rationalize buying another saw. Ron
 
That could easily be a Poulan bar...think I have one like it, only shorter, on my Dayton.

Your Dayton has a bar tail with a profile similar to a 'downsized' version of that bar tail. Your bar will have a 5/16" slot, while the long tom in the ebay listing looks to be 3/8" slot. I have three RN bars like what you've got on your Dayton. One came to me with a Dayton Poulan, another came to me from someone who'd taken it off a Dayton, and another came to me on an early Homelite XL-12 (with the smaller 5/16" studs like a Poulan, rather than the later 3/8" studs).
 
Would someone here just sent me some cash and authorize me to spend it so I can satisfy CAD urgings vicariously - I just missed a $99.00 clean looking PM700 while trying to rationalize buying another saw. Ron

When you find somebody who'll pay for your habit you let me know Ron. Maybe they'll adopt another addict....:D
 

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