McCulloch Chain Saws

[Jethro 2t sniffer]

Which model SDC is on the fixed jet 7-10's. The only two of those fixed jets I have are the PM55 and this new to me PM60. The 60 has an SDC49.

Both my 7-10's have 44's

The 80 or 81 or whatever it is had crappy paint as did a lot of saws of that era. The cover could have been a repaint.

Here's a pic as purchased. I have not tried to track down a full wrap and not likely to.

View attachment 779188

Was thinking even just a nice half wrap for it. The paint you used looks a dam good match Tim well done.

The 7-10s have tillotson carbs can't remember what model ummmm 160 or something lol I'll have a look in about an hour or two for ya
I have 1 sdc fixed jet off of a 60 like yours Jerry the aussie guy who restored that 7-10 a while back for his wall sent it to me and a whole box of screws and all the spare bits he had gathered up for the restoration and wow it's been very handy. Ya meet some good buggers on here

 

[fossil]

Was thinking even just a nice half wrap for it. The paint you used looks a dam good match Tim well done.

The 7-10s have tillotson carbs can't remember what model ummmm 160 or something lol I'll have a look in about an hour or two for ya
I have 1 sdc fixed jet off of a 60 like yours Jerry the aussie guy who restored that 7-10 a while back for his wall sent it to me and a whole box of screws and all the spare bits he had gathered up for the restoration and wow it's been very handy. Ya meet some good buggers on here

Don't other wasting your time looking for the Tilly number I had a look at the 7-10 IPL and I see two adjustable SDC's (44 and 22 ) a fixed Tillotson and a fixed SDC 58

 

[Jethro 2t sniffer]

Don't other wasting your time looking for the Tilly number I had a look at the 7-10 IPL and I see two adjustable SDC's (44 and 22 ) a fixed Tillotson and a fixed SDC 58

No worries I noticed 1 uses an external idle screw and 1 does not. The variations of these saws never ends

 

[fossil]

I have some Tillotson (very incomplete) and a couple of not bad Walbro application charts that show the customer PN's for the carbs and the model they were used on. There was a lot of mix and match as the end user decided without changing PN's.

I did see a Homelite bulletin at some point that told dealers that Tillotson carbs were being used as substitutes for Walbros due to Wallbro's failure to meet deliveries. Most end users likely had that issue as well at times.

As most of us have seen, there are plenty of deviations from what's listed by MAC. I have heard that MAC was the master of service bulletins.

After all, they are just tools.

 

[Jethro 2t sniffer]

I have some Tillotson (very incomplete) and a couple of not bad Walbro application charts that show the customer PN's for the carbs and the model they were used on. There was a lot of mix and match as the end user decided without changing PN's.

I did see a Homelite bulletin at some point that told dealers that Tillotson carbs were being used as substitutes for Walbros due to Wallbro's failure to meet deliveries. Most end users likely had that issue as well at times.

As most of us have seen, there are plenty of deviations from what's listed by MAC. I have heard that MAC was the master of service bulletins.

After all, they are just tools.

Interesting Tim wouldn't be surprised at the supply issues.

Who invented the "cube" carb?

 

[fossil]

I'm guessing Tillotson who claims to have invented diaphragm carbs but I'm going with Rubik on the cube part.

 

[Jethro 2t sniffer]

Haha Rubix cube. It's an hs123B but sure the other 1 was an hs160.

I thought mac had the honor of the diaphragm carb?

 

[Woodslasher]

Unless I see a 50's Tilly diaphragm carb, I've gotta agree with @Jethro 2t sniffer. My 47 and 73 both had diaphragm carbs, but I've yet to see a tilly that I know is older than a Model 47 Mac or a Homelite 17. After I wrote that I realized that the stinkin 17 was just as freakin old as that yaller brick and it has a diaphragm tilly on it! Doggone but Mac was behind in their tech as that 17 feels like a light little cinderblock compared to the McAnvil!

 

[Woodslasher]

I'm gonna get banned from this thread for that bit of Mac-rilege, aren't I?

 

[Jethro 2t sniffer]

Hahahaha macrilige

 

[Maintenance supervisor]

Haha Rubix cube. It's an hs123B but sure the other 1 was an hs160.

I thought mac had the honor of the diaphragm carb?

McCulloch invented the diaphragm carb.

 

[Jethro 2t sniffer]

McCulloch invented the diaphragm carb.

I always thought so too yet if ya read the tillotson web site they are claiming that

 

[heimannm]

McCulloch claimed their 3-25 was the first chainsaw with an all position carburetor, I don't believe they made any claims about inventing the diaphragm carburetor.

Mark

 

[fossil]

Tillotson says late 1940's. There is all kinds of misinformation about who was first. Stihl seems to be pretty good at that. I believe they claim the first one man chainsaw and first chain side adjust tensioner. I guess they never saw a Super 650 Homelite.

Lots of companies claim the have the first one man gas chainsaw. I can find no earlier than the IEL Beaver which I believe was introduced in 1946.

I would doubt that MAC was the first in diaphragm carburetors as they were not in the carburetor business.

I am curious if MAC built their carbs or it was farmed out.

 

[Maintenance supervisor]

Tillotson says late 1940's. There is all kinds of misinformation about who was first. Stihl seems to be pretty good at that. I believe they claim the first one man chainsaw and first chain side adjust tensioner. I guess they never saw a Super 650 Homelite.

Lots of companies claim the have the first one man gas chainsaw. I can find no earlier than the IEL Beaver which I believe was introduced in 1946.

I would doubt that MAC was the first in diaphragm carburetors as they were not in the carburetor business.

I am curious if MAC built their carbs or it was farmed out.

Well just like cars and the news feeds , as long as enough people believe it "they were the first " .
Buick was the first in alot of things but not being around now most of their (firsts) are up for grabs.
I happen to read the mac carburetor info in the History of Chainsaws, whether it is true or not is above my pay grade .

 

[ThistleIA]

There is all kinds of misinformation about who was first. Stihl seems to be pretty good at that. I believe they claim the first one man chainsaw and first chain side adjust tensioner. I guess they never saw a Super 650 Homelite.

My Homie 350,450 & 550 also have the side adjust.Never seen one on a 750.Dont have a regular 650 yet,just the Super.

 

[rarefish383]

I'm gonna get banned from this thread for that bit of Mac-rilege, aren't I?

I just spit turkey gravy all over my keyboard, so I'll vote to keep ya.

 

[fossil]

I think Mark mentioned that MAC switched to aluminum of many of their castings at some point. It's cheaper than Mag but it s 33% heavier which may explain the weight diff between a 7-10 and a 700. It may also explain why the 800, 805, 8200.... and McCinder blocks are so heavy.

I don't know what the PM850 weighs and if it's lighter by some than the later 82 cc versions. I know my 80 or 81 is a few pound lighter than the 800 series.

Question,

Is there any way to tell the difference between an SP80 and SP81?

I have one with no tag with an SP80 winter cover on it but I can see a divider in the transfers on the FW side through the plug hole.

 

[heimannm]

I have 2 or 3 of the SP80 saws but only kept photos of one cylinder that clearly shows no dividers in the transfers. One IPL calls out two different piston options, 85244 (closely follows the 85240 6-10 piston) an 87791 which McCulloch claimed to be interchangeable with the 92519 or "B" piston. I can't find 85244 in any of the McCulloch piston/rings guides but the dimensions for 87791 are slightly larger (0.0004 to 0.0006"). The SP80 IPL also shows the three shoe clutch but that is not a good tell since they are so interchangeable.

In other words, I don't have anything to help you Tim.





Mark

 

[fossil]

Thanks for the reply Mark. I suppose it doesn't matter much. I see you showed a pic of the ever elusive three shoe. Two on mine.

Slowly working on an PM60 right now. New seals in and cleaned up. P&C look great. The exhaust port looks just like a 10-10S port. I wonder if they just up'd the 10-10S design to 62 cc. It's from that era where the yellow paint stuck and the black went to parts unknown.

I need to make a new muffler cover as one corner has disappeared. Thankfully, the duct is solid.