McCulloch Chain Saws

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
That one that Rockcrusher 402 is offering is the one I have that doesn't have a part number. I am not sure what the part number should be, maybe Dan can tell you what he has for a part number.

Mark
From the listing, "This is very early, P/N 65608. There were two very similar variations, so make sure this is the part number you need."
 
OK,today was a bit better out cutting.I got the 10-10S fixed this A.M.but when we got to the wood lot I had a helluva time getting it started,but once it was running it cut great.It stalled out because the idle was set too low & it wouldn't restart.After it cooled off a while It started,but I had to hold the throttle trigger on all the way.My son used it to drop a good sized ash tree & cut on the main part of the trunk.He said it had good power & liked it.

I got to use the 5-10 for the first time today & it ran well too till I hit a rock after only about 8 cuts with a brand new chain.Needless to say I wasn't happy.After we got home with our load of wood I tried to restart the 5-10 & it wouldn't start at all.I sharpened up the chain & tried again.I'm finding out that for some reason that if I use the choke it wants to flood.Only by putting the choke off & holding the throttle trigger wide open will it start.I like the 5-10 better than the 10-10S because it's lighter & is more powerful.
Depending on the carburetor I usually just start "no choke, high idle" first, which most of the year its 70° or above here so not necessary to start the McCulloch saws on choke.
If I haven't started them in a while (month or longer) I'll choke them.
Thing is I've gotten better at building the cube carbs so the pop off pressure of the needle is better on my more recent rebuilds and they usually need a choke.
Are you gaping your coil to flywheel with a index card or business card?
 
I wish I could tell you my part numbers were completely accurate but some of the parts I received were not in original packing so I could be in error.

The only difference I see between the two is the slot vs. two holes around the 2:00 position. It should be easy to convert no number into 65608 if needed.

Mark
 
I wish I could tell you my part numbers were completely accurate but some of the parts I received were not in original packing so I could be in error.

The only difference I see between the two is the slot vs. two holes around the 2:00 position. It should be easy to convert no number into 65608 if needed.

Mark
That's the only difference I see as well. Mine has the two holes so it'll work perfectly. I can't help but wonder if the two are functionally interchangeable or if two holes vs a slot is really that important.
 
Depending on the carburetor I usually just start "no choke, high idle" first, which most of the year its 70° or above here so not necessary to start the McCulloch saws on choke.
If I haven't started them in a while (month or longer) I'll choke them.
Thing is I've gotten better at building the cube carbs so the pop off pressure of the needle is better on my more recent rebuilds and they usually need a choke.
Are you gaping your coil to flywheel with a index card or business card?
I haven't gapped the coils on either saw.The 10-10S is electronic & the coil on the 5-10 is the old style points coil.I have a Tecumseh air gap tool which is .012,which I believe is the correct setting for both air gaps.
 
I think I feel same way about my 7-10. I have a beautiful 10-10s that cuts strong, but not sure if I'll ever pick it up over my 7-10 which has more power, bigger engine, and is lighter.

Put that S engine in an older mid 70s or earlier 10 series shell and you'll run it more often.
 
I feel kinda guilty, I just got a nice envelope from Iowa which reminded me that I'd forgotten to order the rest of the parts I need from ebay. I immediately ordered them, but we'll see if they get here before I'm gone. Also, I should be getting a new old tank for my 1-42 Friday so whenever I get back to wrenching I'll be able to put it back together. I think I'll run it stock against my ported 1-43, then tighten up the squish on it (if possible) and run it against the 1-43 again, then port it as well and run them against each other again so I can see what helps those saws the most.
 
Further to my recent post. Just bought another promac 55. The first had a bad cylinder and piston this one I've just purchased has a bit of compression - looked in both ports and cylinder and piston look ok. That's why I'm wondering about the rings being a bit sloppy?
Anyway it had no spark so I cleaned up the points and put the condenser from the parts saw on ..good spark. Carb was really grotty, tarnished with old oil. Cleaned up but not sure? Investigate another day. The problem is...even with a bit of fuel down the plug hole or carb it will not fire, not even a cough. Any ideas?
 
Leaky crank seals?

Not a cough seems extreme though, maybe too much fuel. Make sure the plug is dry?
This saw has been sitting for a long time judging by the sludge in the tank and carb. I put a little bit of oil on the piston I'm wondering if the crank is full of .... and all I'm doing is pulling up crap fuel which won't ignite. There's definitely fuel vapour coming out of the decomp. When pulling over..maybe I should strip down and take a look?
 
Your compression may be so low that it can't fire.If possible do a compression test on it & if it's lower than 110psi.,chances are it's too low.Even if it fires at 110 psi.,the compression would be so low that it wouldn't have much if any power.A "bit of compression" isn't enough for a saw to fire.
 
Finally getting back to the 7-10. I'm ready to drop the piston and crank in, and I noticed that the way the cylinder is way down in the case, I can't see how I cold get a ring compressor on it. The cylinder is chamfered so it looks like I could just slide the piston in and it will compress the rings. But, I don't want to take a chance and bugger it up. Does the piston just slide in? Do I need to fab some kind of compressor? Thanks.
 
You can carefully work the piston and rings into the bore without the use of any ring compressor. Make sure that the ring gaps are aligned with the locating pins or you will have problems.

My first 7-10 had thick rings and I broke one trying to put it together not being aware of the locating pins, this was the thick ring version so the rings are cast iron. Bob Johnson came to my rescue in that case.

The -10 saws I had worked on up to that point did not have locating pins.

Mark
 
Wow, glad you said that. The service manual I have said if the piston did not have pins, locate the ring gaps on opposite sides. I didn't see the pins on the new piston. The old heavily scored piston they were easy to see. The new piston from Bab, came with the rings already on it. They had enough out ward tension they just rotated over the pins and I didn't see them. Holding them in, they hung up and I found them. So, yes they do have pins. Thanks Mark.
 
Was trying to mill some yellow wood (black locust?) here with my 7-10. A few minutes in I notice that the chain isn't oiled and becoming more tight and difficult to move. So of course I stopped.
I've cleaned the bar (the channel), and I've had the oiler open and have adjusted the nuts to open for more oil. But still, the oil seems to be stuck and not at all enough coming through. When I open the side, I see that the tail end of the bar has
oil on it, but nothing much and nothing is moved onto the chain and out. Additionally the sprocket also moves a bit up and down on its axis, wonder if its worn out and I should replace it. If so, I guess I have to take the clutch off. Anyone has had similar issues with oil supply to the bar, and what did you do to resolve it?

Cheers
Simon

EDIT: OK, never mind - I think I fixed it. Opened up the oiler even more and plenty oil is coming through when the bar is off. Will clean the holes and groove in the bar again and it it's not working its the bar, not the oiler I guess.

1616734433040.jpg1616734433036.jpg
1616734433031.jpg
 

Latest posts

Back
Top