McCulloch Chain Saws

[edju1958]

McCulloch Kid,it's not uncommon for compression to come back up after a saw has been sitting for a long period of time (decades).You were correct in your assumption that the rings & cyl.are so dry that it caused low compression.Of course that carbon build up is most likely the contributing factor to it having low compression & the no fire.
I agree with Goinwheelin & Poge to tear it apart & clean it.I have a 1-71 that I did have run on a prime when I got it a couple of months ago,but I'm not able to work on it just yet due to having surgery last month.I also have a 1-75 (95cc) that runs strong,but the bozos who worked on the clutch didn't put the rivet spacers back in & the result is a clutch's starter pawls that don't engage on the starter drum.

 

[edju1958]

Mark,I got the throttle cable off the PM310 the other day after I had to completely dismantle the handle assembly.The cable sheathing was broken in about 3 or 4 places due to heat & old age.I was only responsible for one break as far as I know.
Would it be possible to use a small fuel line (1/16 ID) to put on over the throttle cable & re-install?

 

[edju1958]

I was the winner of 2 PM6s yesterday on Feebay ($49).The one saw is complete & runs on a prime,the other is a parts saw.This is to replace the saw that was stolen.

 

[edju1958]

Ed - the wire inside the throttle cable is 0.030" diameter and fairly stiff.

1-71 is a desirable saw but not really a kart engine. Take the time to disassemble and clean it thoroughly, one chunk of that carbon in the cylinder could be bad.

FWIW a page or two back...there were 3-10 saws before there were 310 saws.

Mark

I forgot all about the 3-10,probably because I don't have one (yet).

 

[heimannm]

I don't think fuel line would work for the sheath on the throttle cable, too soft and the wire would either drag too much or dig right into the sheath and hang up. If you could find some 1/8" I.D. nylon tubing used for air or grease lines it might work. If you can wait a few days, I hope to start on your 300 saws tomorrow and can send a couple cables with them when I send the saw(s) back.

If you want to try and McGyver something in the mean time, the sheath needs to be 8-1/2" long and the hook end needs to extend 1-7/16" (+/-) to work properly.

I am hoping to chronicle the rebuild of the SE2114 (300 Series Silver Eagle) in the Mini Mac Small Saws thread and I'll put some photos over there for reference. I'll include a helpful little tip for getting that handle put back together with the new cable in place...the throttle return spring is pretty strong and it makes holding everything in place while you assemble the handle a real challenge.

Mark

 

[heimannm]

On another note, Bob Johnson called this afternoon to talk about alternatives for the NLA 85898 lower mount used on many of the SP and PM model saws. The illustration below is from IPL #215724-R1 and is the only one I have seen that references the alternative 92704/92703 (Items 31 and 30 in the circle) to 85898 (Item 31 in the main illustration). (EDIT - 213799-R1 has the same illustration and parts list.)To add to the confusion the hub (Item 30) is AKA 94038 in the 300 Series saws where the same mount is used on both ends of the top handle. There are too many problems/inconsistencies with this illustration to try and describe them all, but I'll note a few as we carry on this discussion.



To compound the confusion, most of the IPLs use the illustration in the circle but use the 85898 part number for the mount and 84661 for the grommet which is correctly shown as Item 30 in the main illustration above. If you were not familiar with the saws and the parts I think looking through the IPL's while looking at your saw with broken/damaged/missing parts could cause you to pull your hair out.

This is what 85898 is supposed to look like.



And this is how you often find them.



On a positive note, since the rubber in the center of that mount is intact, you could just assemble the parts in the saw and it would function as intended. On many that I have taken apart the rubber inside is badly deteriorated and the mount is basically worthless as it is.

This is the mount 92704 and hub 94038 (AKA 92703). This one does not have the steel ring around the outside.



Assembled.



85898 with the washer and grommet 84661 shown assembled in the correct sequence. Note that this set up uses a normal 1/4-20 screw (they call it 2" but I find 1-3/4" works better) but the illustration calls for a shoulder screw (93096) which is actually required with 92704/92703.





I don't have any of the shoulder screws 93096 on hand but I surmised that the shoulder must be 5/16" diameter and 1" long with standard 1/4-20 threads beyond. I made my own with a 1" long spacer over a 1/4-20 screw. According to the IPL's & part lists, this is how the two different parts would appear in the saws, 85898 on top and 92704 below.



I like the larger washer with the grommet as a "range limiter" if the mount fails so I made a longer spacer and added a couple of grommets to mimic the original 85898 set up.





For anyone with fewer than 300 posts, I will charge $5.00 for every subsequent answer...

Mark

 

[edju1958]

I don't think fuel line would work for the sheath on the throttle cable, too soft and the wire would either drag too much or dig right into the sheath and hang up. If you could find some 1/8" I.D. nylon tubing used for air or grease lines it might work. If you can wait a few days, I hope to start on your 300 saws tomorrow and can send a couple cables with them when I send the saw(s) back.

If you want to try and McGyver something in the mean time, the sheath needs to be 8-1/2" long and the hook end needs to extend 1-7/16" (+/-) to work properly.

I am hoping to chronicle the rebuild of the SE2114 (300 Series Silver Eagle) in the Mini Mac Small Saws thread and I'll put some photos over there for reference. I'll include a helpful little tip for getting that handle put back together with the new cable in place...the throttle return spring is pretty strong and it makes holding everything in place while you assemble the handle a real challenge.

Mark

Thanks Mark,I'll take all the help I can get on this little devil! I thought if I put some lube in the sheath it'd reduce the drag.I saw a video on YouTube where a guy said (& showed) that he used a sheath from a #10 house wire (I think #10 is too big,more like #12 or #14 wire).I did some measurements & the wire of the cable is 1/32 in.(as you said .030),& the O.D.of the sheathing is 5/32.I do have some bits & pieces of house wiring,but it might be a challenge to get the copper wire out of it.If I went to a scrapyard they probably have a bunch of it laying around.

 

[PogoInTheWoods]

For anyone with fewer than 300 posts,...

Or more than one 300 series saw on your bench?

 

[vinnywv]

On another note, Bob Johnson called this afternoon to talk about alternatives for the NLA 85898 lower mount used on many of the SP and PM model saws. The illustration below is from IPL #215724-R1 and is the only one I have seen that references the alternative 92704/92703 (Items 31 and 30 in the circle) to 85898 (Item 31 in the main illustration). To add to the confusion the hub (Item 30) is AKA 94038 in the 300 Series saws where the same mount is used on both ends of the top handle. There are too many problems/inconsistencies with this illustration to try and describe them all, but I'll note a few as we carry on this discussion.

View attachment 949126

To compound the confusion, most of the IPLs use the illustration in the circle but use the 85898 part number for the mount and 84661 for the grommet which is correctly shown as Item 30 in the main illustration above. If you were not familiar with the saws and the parts I think looking through the IPL's while looking at your saw with broken/damaged/missing parts could cause you to pull your hair out.

This is what 85898 is supposed to look like.

View attachment 949132

And this is how you often find them.

View attachment 949133

On a positive note, since the rubber in the center of that mount is intact, you could just assemble the parts in the saw and it would function as intended. On many that I have taken apart the rubber inside is badly deteriorated and the mount is basically worthless as it is.

This is the mount 92704 and hub 94038 (AKA 92703). This one does not have the steel ring around the outside.

View attachment 949134

Assembled.

View attachment 949135

85898 with the washer and grommet 84661 shown assembled in the correct sequence. Note that this set up uses a normal 1/4-20 screw (they call it 2" but I find 1-3/4" works better) but the illustration calls for a shoulder screw (93096) which is actually required with 92704/92703.

View attachment 949137

View attachment 949136

I don't have any of the shoulder screws 93096 on hand but I surmised that the shoulder must be 5/16" diameter and 1" long with standard 1/4-20 threads beyond. I made my own with a 1" long spacer over a 1/4-20 screw. According to the IPL's & part lists, this is how the two different parts would appear in the saws, 85898 on top and 92704 below.

View attachment 949138

I like the larger washer with the grommet as a "range limiter" if the mount fails so I made a longer spacer and added a couple of grommets to mimic the original 85898 set up.

View attachment 949139

View attachment 949140

For anyone with fewer than 300 posts, I will charge $5.00 for every subsequent answer...

Mark

Also the handles for the sp40 and 510 saws as well as 155 or 165 used the same inner barrel in their handles. Part 91171. They have a skirtlike grommet on them that pulls right off. Once its off the inner part of that mount can be used. For the sp mount. Search ebay for "mccullich 91171" to see what part im referencing to. A picture is attached

 

[knightmax]

On another note, Bob Johnson called this afternoon to talk about alternatives for the NLA 85898 lower mount used on many of the SP and PM model saws. The illustration below is from IPL #215724-R1 and is the only one I have seen that references the alternative 92704/92703 (Items 31 and 30 in the circle) to 85898 (Item 31 in the main illustration). To add to the confusion the hub (Item 30) is AKA 94038 in the 300 Series saws where the same mount is used on both ends of the top handle. There are too many problems/inconsistencies with this illustration to try and describe them all, but I'll note a few as we carry on this discussion.

View attachment 949126

To compound the confusion, most of the IPLs use the illustration in the circle but use the 85898 part number for the mount and 84661 for the grommet which is correctly shown as Item 30 in the main illustration above. If you were not familiar with the saws and the parts I think looking through the IPL's while looking at your saw with broken/damaged/missing parts could cause you to pull your hair out.

This is what 85898 is supposed to look like.

View attachment 949132

And this is how you often find them.

View attachment 949133

On a positive note, since the rubber in the center of that mount is intact, you could just assemble the parts in the saw and it would function as intended. On many that I have taken apart the rubber inside is badly deteriorated and the mount is basically worthless as it is.

This is the mount 92704 and hub 94038 (AKA 92703). This one does not have the steel ring around the outside.

View attachment 949134

Assembled.

View attachment 949135

85898 with the washer and grommet 84661 shown assembled in the correct sequence. Note that this set up uses a normal 1/4-20 screw (they call it 2" but I find 1-3/4" works better) but the illustration calls for a shoulder screw (93096) which is actually required with 92704/92703.

View attachment 949137

View attachment 949136

I don't have any of the shoulder screws 93096 on hand but I surmised that the shoulder must be 5/16" diameter and 1" long with standard 1/4-20 threads beyond. I made my own with a 1" long spacer over a 1/4-20 screw. According to the IPL's & part lists, this is how the two different parts would appear in the saws, 85898 on top and 92704 below.

View attachment 949138

I like the larger washer with the grommet as a "range limiter" if the mount fails so I made a longer spacer and added a couple of grommets to mimic the original 85898 set up.

View attachment 949139

View attachment 949140

For anyone with fewer than 300 posts, I will charge $5.00 for every subsequent answer...

Mark

Good Stuff, thanks Mark!

 

[edju1958]

Last night I went scrolling on Feebay for saws & found a Monkey Wards version of the Eager Beaver 2.1 & 2 Mac 16 in.roller nose bars,brand new for $25 each.Originally the seller wanted $30 or MO.Since he only had 2 left I figured he'd accept my offer of $25 ea.Those will look nice on a couple of 10-10s I've got coming up to work on.
Since I don't have any Monkey Wards saws I thought it'd be a nice addition to my collection.

 

[edju1958]

I rebuilt a couple of carbs today for upcoming projects.The 1st carb was an SDC37 that came on the saw from the seller in Vt.It looked to be in good shape,but when I pressure tested it it wouldn't hold pressure.It's not leaking at the needle.I put nail polish on the welch plugs & it still leaks down fairly quick.Any ideas?
The 2nd carb I rebuilt was a Zama that was in the PM310.The inlet screen well was full of silt.I have no idea how that saw ran at all when I got it.I can't pressure test that carb because I can't find the adaptors for the smaller hoses.I haven't done a Zama in yrs.& I'm surprised the carb didn't get thrown up against the wall.Everything in it is so damned small.

 

[heimannm]

Ed - dunk it in water or clean solvent while under pressure. I suspect you will find it leaking around the fuel pump cover. Does yours have the stamped steel cover or the thicker die cast one? Most of the time Walbro recommended using the thick gasket with the stamped covers and the thinner gasket with the die cast covers.

Look what I found in a box today...did you want me to try and piece together a Mini Mac saw around the rear handle in the box?



I did manage to get everything cleaned up.





The short block with the white oil pump has 130 PSI compression so I'll build the saw around that one.



Mark

 

[edju1958]

Ed - dunk it in water or clean solvent while under pressure. I suspect you will find it leaking around the fuel pump cover. Does yours have the stamped steel cover or the thicker die cast one? Most of the time Walbro recommended using the thick gasket with the stamped covers and the thinner gasket with the die cast covers.

Look what I found in a box today...did you want me to try and piece together a Mini Mac saw around the rear handle in the box?

View attachment 949412

I did manage to get everything cleaned up.

View attachment 949413

View attachment 949414

The short block with the white oil pump has 130 PSI compression so I'll build the saw around that one.

View attachment 949415

Mark

Surprise,surprise!!Didn't I give you the correct parts Mark?I thought I put almost 2 complete 310s in the box?If you need parts,I've got at least 3 more almost complete saws here.I'll figure that 130 psi will come up to around 140-145 psi as that compression test was done on a dry (and I mean dry) cylinder.

As for the carb,it had the thin gasket on it when I took it apart.I didn't exactly like the kit I used,I'll try another one.

 

[edju1958]

I've been writing about the throttle cable here for thPM310 for the past couple of weeks.There the guy on Feebay who wants $60 + shipping for his precious cable.Mark H.has offered to send a couple to me when he gets finished with my saw.I ordered one from Bob J.for around $5-$7,but I can cancel that item on my order with Bob,& I thank you for the offer Mark.I was in the garage today looking for an elusive 10 series RH recoil when I spotted a 3 ft.section of 12/2 house wire & figured what the heck.Getting the black coated wire out of the sheathing was simple,but getting the black covering off the copper wire wasn't quite so easy.I put the bare copper end in the vise & then used a heat gun to gently heat the outer black covering & then pull on it.It moved a few inches at a time & I had to keep going back & reheating the covering.I did that about 4 or 5 times & the next thing I knew I had a new sheath for the PM310!
The old brittle wire covering is on the left in pieces,the new sheath is on the cable.I might have to bend the loop on the end of the cable the other way.

.

 

[edju1958]

I almost forgot - I have to thank you Mark for helping me out with that SDC37 carb.I didn't dunk it in water,but I put a different cover gasket on it & it made a world of difference.I ended up putting an entiorely new kit in it.It leaks down,but ever so slowly.It takes over 4 min.to leak down from 7 psi to 1 psi.This might be acceptable,not sure.Ideally it should hold pressure.I might have to polish the needle seat.

 

[heimannm]

Try wetting the needle with a few drops of fuel in the line before you pressure test. I find that often a wet needle will seal where a dry one will not.

Keep us informed on how the softer PVC sheath works for the throttle.

Mark

 

[bob kern]

Try wetting the needle with a few drops of fuel in the line before you pressure test. I find that often a wet needle will seal where a dry one will not.

Keep us informed on how the softer PVC sheath works for the throttle.

Mark

Great “ tip” mark!! Might be pestering you this week as I attempt to put mystery Mac back together.

 

[PogoInTheWoods]

Keep us informed on how the softer PVC sheath works for the throttle.

Small diameter rigid tubing (with an acceptable bend radius for the purpose) is readily available. Automotive vacuum line comes to mind...

 

[edju1958]

I got the 2 PM6s today.I went through them briefly.The saw that's whole has unbelievable compression,it's like the saw is new.
The parts saw is just missing the coil & fuel line.It has a good P&C though.The carb is good too,but needs a rebuild.