McCulloch Chain Saws

[cpr]

That's an SP-125 intake and reeds.

 

[db456]

Reeds

Should be OK in the CP 125, right?

 

[cpr]

Yes, better, I believe. I think the twin reed has more surface area than the big single, plus the twin petals are much easier to get if they let go.

 

[carldebjez]

740 Bar?

Carl we'd have to see the tail end of that bar to tell you whether or not it'd fit the 740. 30" cut length bar should take 93-94DL of .404 on these saws when using a .404-7 sprocket/rim. Depends on the exact bar however. My 31" cut length Cannon RN fits my 740 and 790 fine with 95DL of .404 on a 7 pin rim. Same chain loop fits my 30" cut length Cannon RN on my Homelite XP1020 with a .404-8 rim.

I should have attached these in the first place! Slot is 14.5mm wide.
Not sure what is going on with the worn groove and broken backing of the oil slot ? Hopefully doesn't effect function of bar/oil feed (even if it can only be used on one side). The Mrs is picking the saw up this arvo so better clean the bench so we can check it out tonight..

 

[cpr]

Definitely one-side only unless you pack it off to a bar shop...

Never seen a tail like that before. Very interesting, thanks.

 

[leeha]

Definately a modded bar. The holes are not consistant.
The oil holes look to be added. The 14mm slot looks ok
but the yellow bar tip says Mac but that could have been
painted at anytime. I would guess maybe a large Stihl or
Sachs Dolmar mount that someone got very creative and
made it work on the Mcculloch.




Lee

 

[carldebjez]

The bar has a large etched oval logo with the words "McCulloch - Fortified Tip" in the oval, on both sides. Will get close up tonight. Carl

 

[struggle]

I know this is a bit of a stretch but I am looking for another SP125 (PHO).

If there is one out within a reasonable reach drop me a PM of details. I might have something to offer in trade as well. depending on what you are intrested in.

 

[paccity]

carb question , was down playing around with my new to me super 250 . trying to get her to prime . no luck. a kit is in order. the first pick is the carb off of the super the second is on the unleaded 250. identifying the carbs is one of my questions , . i think one is the mac carb the one on the reg 250 is a tilly? i've read some of you ##### about the mac carbs . sould i try to find a tilly to replace it or go threw the mac carb.

 

[struggle]

First one looks like the dreaded flat back and the second one is the tilly.

Mark H I think has a very good write up about the flat back. I would not give up right away on it but I also have not worked on one yet.

 

[Eccentric]

Definately a modded bar. The holes are not consistant.
The oil holes look to be added. The 14mm slot looks ok
but the yellow bar tip says Mac but that could have been
painted at anytime. I would guess maybe a large Stihl or
Sachs Dolmar mount that someone got very creative and
made it work on the Mcculloch.




Lee

The bar has a large etched oval logo with the words "McCulloch - Fortified Tip" in the oval, on both sides. Will get close up tonight. Carl

Looks/sounds to me like it WAS a large frame Mac bar, and it has been shade-tree modified to run on a Sachs-Dolmar or big stihl. That's a shame.

First one looks like the dreaded flat back and the second one is the tilly.

Mark H I think has a very good write up about the flat back. I would not give up right away on it but I also have not worked on one yet.

+1.

The first carb is a choke type flatback, as used on some S-250, S-550, and 650/660 Macs. The second carb looks to be an HL63. Use it WITH the adaptor (that is between the carb and the 250) on a front-tank Mac, or WITHOUT the adaptor on a top-tank Mac.

 

[Eccentric]

Hey Fraser.......what is that bracket on the right side of the 250 carb box, over the oiler pushrod? That's not OEM...

 

[paccity]

Hey Fraser.......what is that bracket on the right side of the 250 carb box, over the oiler pushrod? That's not OEM...

i really don't know. theirs a grommet next to it you can see. thats a question i was going to ask in time. i'll take some better pic's of it and see if we can speculate over what it is or was.

 

[heimannm]

Some one had that 250 set up to run a brush cutter.

I have the IPL's for the brush cutter in hard copies but not scanned, that bracket is part of the throttle set up.

Mark

 

[leeha]

carb question , was down playing around with my new to me super 250 . trying to get her to prime . no luck. a kit is in order. the first pick is the carb off of the super the second is on the unleaded 250. identifying the carbs is one of my questions , . i think one is the mac carb the one on the reg 250 is a tilly? i've read some of you ##### about the mac carbs . sould i try to find a tilly to replace it or go threw the mac carb.



Me personally, I have about given up on Flatback carbs.
You can't find primers so you have to self prime to start
them when cold and sometimes hot. The diaphram kits
are expensive at 30 bucks. Can't find the needle and seats.
You can rebuild and install the HL Tilly and have a much
more dependable running saw. Just have to make the throttle
and choke rods. Well worth the effort.



Lee

 

[HeRoze]

Hey - what kind of carb do I have here? I tore it down, cleaned and reassembled. Replaced the inlet welch plug after cleaning inside. The gaskets look good so I just reused. Any tips on initial settings? H/L 1.25/1? Thanks! Vic

View attachment 225690

 

[Aaron441]

.404 drive link question

I just aquired a McCulloch .404 36" guide bar to fit my 380. Anybody know how many drivers the chain should be? The only number on it is36m0x63snb. Thanks

 

[heimannm]

Me personally, I have about given up on Flatback carbs.
You can't find primers so you have to self prime to start
them when cold and sometimes hot. The diaphram kits
are expensive at 30 bucks. Can't find the needle and seats.
You can rebuild and install the HL Tilly and have a much
more dependable running saw. Just have to make the throttle
and choke rods. Well worth the effort.



Lee

I was talking with Bob Johnson before I left, Bob tells me he has the diaphragm and gasket kits for the flat back for $20 now. The needle is the same as the Walbro SDC.

Primers are a bit of a problem, I was fortunate to watch e-bay and get a few spares for the saws I like to have ready to go. For a GTG saw I don't mind having to give it a shot of prime to start.

Vic - that is a bit of an oddball that only appears on some of the D-30/36 and 1-40 saws. I think it is also a McCulloch by Walbro, the fuel pump diaphragms and gaskets are on e-bay quite a lot, Bill Robinson (Fayetteville Repair) and APSE have them as well. I have a few of them myself, but no spare metering diaphragms. In fact, I am not sure what the metering diaphragm looks like since I haven't had one apart in quite a while.

Mark Heimann

 

[HeRoze]

==== In fact, I am not sure what the metering diaphragm looks like since I haven't had one apart in quite a while.

Mark Heimann

Wow - pics turned out HUGE! I scanned when I had them apart, with a 1" scale.

View attachment 225727View attachment 225728

 

[heimannm]

It sure looks like the same metering diaphragm as used in the other flat back carburetors. The fuel pump section is quite different from the other flat backs however.

If you can't find the parts you need, contact me in a few weeks when I am home again and I expect we can set you up.

Mark