McCulloch Chain Saws

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The spacer in the front of the tank is dependent on the tank itself, not so much related to the cylinder.

Some of the 6-10 tanks with the spring loaded H/L adjusters uses a substantial spacer between the fuel tank and oil tank (68219, 1/4" high), most just have and insulating washer there.

Mark
 
Tanks are cross cross compatible. The handle brace is different and guessing the shield is different on a 70CC saw. If you could find a mostly there 7-10 or 700 you could swap the tank, but at that point you may as well go for the 70 cc option :)

Nothing on ebay for those which surprises me since they made them into the late 90's......Figured they'd still be popping up.

Pretty sure Max would have a short block of a 57CC saw too, but his stuff is all NOS and being so is not a low cost option. Would literally be a new saw though....

Not the first time I've heard about LRB pistons being problematic (wish it wasn't so). I've mostly heard the pins they supply walk out and the bearings come out and damage everything but the bottom end. I understand the solution is using the original piston pin so it doesn't walk out.

If I see anything pop up, I'll give you a holler.

Brian
Thanks I'd go NOS but $$$ are not my friend. Being retired and a limited income monthly makes it cost prohibitive. I've been dicking around with a guy about a 1/2hr away he has a complete saw for $30 but rarely returns my messages. So I wait it out. 👍
The crank bearing and bushing are different as well as other areas unless I use complete engine.
Swapping out top end is what I'm talking about when I say a lot of work.
 
Thanks I'd go NOS but $$$ are not my friend. Being retired and a limited income monthly makes it cost prohibitive. I've been dicking around with a guy about a 1/2hr away he has a complete saw for $30 but rarely returns my messages. So I wait it out. 👍
The crank bearing and bushing are different as well as other areas unless I use complete engine.
Swapping out top end is what I'm talking about when I say a lot of work.
Best of luck on the $30.00 option Jeff, It sounds promising if he'll get it done...

Brian
 
Black full wrap handlebar and the holes in the AF cover would indicate a Super 250. He mentioned a 650 but the 660 (gear drive) also has that AF cover. You could see it is in fact a direct drive saw when he briefly rolled it over to look at the numbers on the bottom. My notes say the block number for a Super 250 are 62481 which doesn't agree with 63436 that he reads off the bottom. He also say 2 1 5 but maybe he's a bit dyslexic and it is actually a 1-52 with the Super 250/660 AF cover and the serial number is 63436???

Mark
 
I got a question I have a mac 650 the one that looks like a 610, the manual oiler seems to be fine but the auto oiler portion of the pump is acting up , where should look first and is there a number of turns in or out on the oil adjustment screw as to where it should be?
 
The piston in the pulse (automatic) pump is probably stuck. You may be able to free it by turning the screw fully clockwise then backing it back out 5 or 6 turns. Turning the screw clockwise limits the travel, but if you go all the way you might just push the piston far enough to break it free then back the screw off again to allow the piston to cycle from the impulse signal.

If that doesn't do it you will need to take the oil pump off the top of the tank (4 screws) and work the pump out so you can turn it over and cycle the piston manually to free it up.

Mark
 
I have come across a saw which is missing a lot of parts. It still has the clutch and flywheel so I can tell it is RH start. It has the 2-10/6-10 etc. compression release which is operated by the black stop switch in the rear handle. The only numbers on the saw are at the base of the cylinder. They read "A16-4800"

Except for missing the starter, filter cover and exhaust, it would look just like the 6-10 Mark recently posted (see image below). Can this be ID'ed?

 
Which carburetor Matt? There were 2-10's and 6-10's with cube type carburetor and 3-10's and 5-10's with the bullfrog carburetor. The "Pro Mac" style tank top would certainly suggest that it is a 6-10 but so many parts are interchangeable.

Check the bore (probably easier through the intake side than exhaust), 1-3/4" is a 54cc and 2" is a 70cc.

The cylinder on the 70cc saws are larger in diameter and have extra fins, but that can be hard to see when the saw is fully assembled.

I presume the 7-10 has an auger drive attachment, but I would have expected another handle/extension to accommodate the torque generated.

The exposed chain with the spike makes it look like something Mad Max would have used...

Mark
 
I have come across a saw which is missing a lot of parts. It still has the clutch and flywheel so I can tell it is RH start. It has the 2-10/6-10 etc. compression release which is operated by the black stop switch in the rear handle. The only numbers on the saw are at the base of the cylinder. They read "A16-4800"

Except for missing the starter, filter cover and exhaust, it would look just like the 6-10 Mark recently posted (see image below). Can this be ID'ed?


Post a picture of the underside please.
 
Hi Mark, the carb is missing but it is setup for the SDC style carb, not the bullfrog and, as you say, has the "Pro Mac" style tank. The tank is what made me think it probably isn't a 2-10. I don't have access to the saw to measure the bore, so I might just have to buy it and see if I can get it cheap enough. I will have to take a good look at the saws I have and see if I can identify the fin differences when assembled.

I thought similar about the 7-10. The torque would be interesting. It is coming from Queensland Australia. Mad Max would be no match for some of our men up there! I bought it for the saw, but the attachment is a bonus.

Hi Rocker59, I would, but I don't have access to the saw. What are you expecting to see other than the number I posted?
 
Hi Mark, the carb is missing but it is setup for the SDC style carb, not the bullfrog and, as you say, has the "Pro Mac" style tank. The tank is what made me think it probably isn't a 2-10. I don't have access to the saw to measure the bore, so I might just have to buy it and see if I can get it cheap enough. I will have to take a good look at the saws I have and see if I can identify the fin differences when assembled.

I thought similar about the 7-10. The torque would be interesting. It is coming from Queensland Australia. Mad Max would be no match for some of our men up there! I bought it for the saw, but the attachment is a bonus.

Hi Rocker59, I would, but I don't have access to the saw. What are you expecting to see other than the number I posted?
If the shroud is flat on the bottom, it is likely a 5/6/7-10 (early 7-10s had the DSP and a keyway on both ends of the crank). If it has a depression towards the front, it is a 2/3-10. The Super 2-10 had the Super tank that became the Pro Mac tank. The 5-10 had the cast aluminum handle brace (similar to the 2-10). The 6/7-10 has the steel brace with the second bolt at the rear. That being said, there are very few stock working saws out there.
 
Also, there was a factory conversion kit available. to convert a 5-10 to a super tank and a walbro or tillotson carb.
 
If the shroud is flat on the bottom, it is likely a 5/6/7-10 (early 7-10s had the DSP and a keyway on both ends of the crank). If it has a depression towards the front, it is a 2/3-10. The Super 2-10 had the Super tank that became the Pro Mac tank. The 5-10 had the cast aluminum handle brace (similar to the 2-10). The 6/7-10 has the steel brace with the second bolt at the rear. That being said, there are very few stock working saws out there.
Thanks. I will try to check those details. I have a fair range (10 or so) of 10-series saws here that I can look at to familiarize myself with those differences.

I am starting to get more into these smaller frame McCullochs, I am pretty good with the front tank large frame saws (e.g. 250, 380, 450, 550, etc.) but I am not fully up to speed with all the differences in these later saws, seems the more I learn the less I know. The differences minor in these things seem vast.
 
Going thru this S550. Internals were better than I expected. There was no sign of moisture just stuck rings. Piston bearings were loose so I installed a NOS piston assembly. Gave the bore the old scotchbrite deglazing and put it all together with new main bearings and better rod needles.

IMG_20240223_12228.jpgIMG_20240223_14102.jpgIMG_20240223_13832.jpgIMG_20240222_3747.jpg
 
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