McCulloch Chain Saws

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Had a pleasant surprise today , bought a ProMac 700 from the local saw shop about 4 months ago and rebuilt the carb and it still leaned high rev , had a short needle sdc 44a on it so I got the long needle with boot from Chainsawr and rebuilt it.
I figured this saw needed seals , when I tried the short 44a on my pro 60 guess what, lean high rev.... I put the rebuilt long needle 44a on the pro 700 and BINGO!
FYI the 8 pin rim sprocket did not work with a standard size chain and I salvaged this on from the scrap yard, its a 72dl, 71dl would be perfect.
 
Check all your connections,especially the ground.Those Atom chips have been around for about 20 yrs.,maybe longer.I wonder if it's possible that after all that time it may be starting to break down?You could get a new chip for about $20 & see if that makes a difference.
Ed

I checked all connections. The wire nuts they supply with the Atom chip seemed loose. I replaced that with a crimp connector. Saw seems to run better now on top. However, having a hard time getting saw to idle and low side isn't as crisp as I'd think it should be.

Sounds like I need to get back into the carb.
 
Trying to bury my head in the sand on that thought. :dumb:

If it turns out it needs seals that'll be fine, this saw is worth fixing that for sure!

Honestly I think if you are gonna chase the rabbit down the hole , by eliminating possible malfunctions pick up a condenser and points they're cheap enuff and it'll put to rest any possibility that the chip is doing weird stuff.
Lots of people modify their saws ,after buying a bunch from scrap heaps and various places I'm suspicious of any nonfactory parts , like the sign at a garage says " 50$ an hr ,100$ if you tried to fix it"
 
Ahhh Sunday morning a hot stiff coffee and a report from blind squirrel falling. Yup every thing is right today:) thanks Ron and Brian.

Ps .What thread is your 800 studs? I lost a 7-10 nut and the 800 was wrong thread seemed kinda odd

IPL say M8. I believe the 7-10 is SAE 5/16" 24.

Ron
 
Honestly I think if you are gonna chase the rabbit down the hole , by eliminating possible malfunctions pick up a condenser and points they're cheap enuff and it'll put to rest any possibility that the chip is doing weird stuff.
Lots of people modify their saws ,after buying a bunch from scrap heaps and various places I'm suspicious of any nonfactory parts , like the sign at a garage says " 50$ an hr ,100$ if you tried to fix it"

I've got extra points and condenser from my sp80 parts. Might just try them out. I agree, hate trying to fix other people's mods, most of the time they do more harm than good.
 
IPL say M8. I believe the 7-10 is SAE 5/16" 24.

Ron

Ahh right like the 610 had gone metric. Odd buggers the rest of the 800 is imperial had me scratching my head when I went to borrow a bar nut from it lol.

I have a bag full of the 5/16 nuts now after losing 1 went down to the fastener shop and boy did they give me a strange look imperial stuff is real oddball here now. Old English and American cars and machinery would be the last users of it really
 

Had a pleasant surprise today , bought a ProMac 700 from the local saw shop about 4 months ago and rebuilt the carb and it still leaned high rev , had a short needle sdc 44a on it so I got the long needle with boot from Chainsawr and rebuilt it.
I figured this saw needed seals , when I tried the short 44a on my pro 60 guess what, lean high rev.... I put the rebuilt long needle 44a on the pro 700 and BINGO!
FYI the 8 pin rim sprocket did not work with a standard size chain and I salvaged this on from the scrap yard, its a 72dl, 71dl would be perfect.


That's a very nice 700 you have there. Bet youl bring that out with ya every time now
 
That's a very nice 700 you have there. Bet youl bring that out with ya every time now
I will more often now! The 8 pin rim sprocket is really impressive with the 20" bar I know no one can tell how hard that log is from a video but it's stout! Spalded oak.
My Every day saw is my pm700 with the 24" bar and a new loop of full skip chisel, I've been cutting some very sappy pine lately and the full skip does help alot . Over the next couple of weeks I'll be trying some different things with my saws to see what I like ,like spocket ratio and chain type , I just ordered some square cut chisel in semi skip in 70dl and 60dl .
 
Good info, but that's for a hi and lo adjustable sdc. That shows the tan diaphragm as I think #25 which is between pump diaphragm and fiber gasket. However, why is it shown off to the side? Is it not suppose to be used in some models?

So when carb is fixed hi jet, still start with lo screw out 1 turn? When I got saw it was at least 2 or so turns out.
 
Bad seals will do that also.

Well think I'm definitely leaning towards air leak on the sp81. I went through the stock fixed jet carb last night. It is spotless with good diaphragm and gaskets. Fuel line and filter are perfect. The tan check diaphragm was out of order, I fixed that. Adjusted needle arm.

Just ran saw and it doesn't idle well. You try to bring idle up and it just keeps wanting to climb. I started with lo jet 1.5 turns out. Turned it in a bit, no change. Started turning it out...2.0, 2.5, 3.0 turns out....revs just kept climbing. My guess is if it'll keep taking fuel like that then it's pulling in air.

Unless someone tells me otherwise not sure it's even worth trying points and condenser on this saw? I'm thinking carb boot under tank or crank seals are no good.
 

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