McCulloch Mini and Small CC Chainsaw's

[Roanoker494]

Grandpa's old 110 that I inherited.

Mac Cat that came in a bundle deal yesterday.

 

[MacAttack]

Question: Got a McCulloch Wildcat that someone dumped Bar Oil in the Gas Tank. I got it cleaned up and running…issue is that it is kind of a challenge to start (about 15 pulls or so). Once it gets warmed up though, it starts up RA FH time. Idles perfectly. Revs up perfectly…just a little cagey cold starting.

anyone else have issues starting this model of saw? I bought a carb kit…just can’t decide rather I want to rebuild the carb or just deal with it…

The choke like was mentioned. Or also if the fuel pump diaphragm is still, it won't pump the gas as well to get running.

 

[MacAttack]

The MM 35 "Franken-Mini" is together and ready to test run! This saw is an oddball with that cutout in the housing for the "auto sharp" that's long-gone. I'm hoping the old Mini Mac 6 clutch cover will keep things from hitting me in the face, haha.
By the way, this saw also uses the later air cover that's held in place by a screw. If anyone had one of these covers from a Mac 120, Eager Beaver 2.0, that they didn't need I'd be interested in buying it.
The only air cover I have is kind of broken, and has the clasp.

 

[Alaskan Stihl]

Slowly but surely…I am getting all these saws up and running as they should! It is kinda cool to go cut wood…and be able to have a whole selection of saws to choose from!

Next on the rack is a McCulloch 110. Problem with this one…is that it runs when primed…but once fuel is spent…it dies. I went ahead and ordered a Carb Kit (still waiting for it to arrive), however; I do have it all disassembled and ready to fix once gets here. Problem is though…anyone who has worked on these saws discoveres that you have to remove the coil to disconnect the Carburetor. I have read & researched to find out what the correct Flywheel/Coil Gap is suppose to be…and all the recommendations seem to be differnt.

Question #1. Does anyone know exactly what the “Flywheel/Coil Gap” is suppose to be?

Question #2. (Different chainsaw). I also picked up a 10-10 in the mix and got it running as well. Holy-Smoly that bugger has some freaking compression though! When I start it, I have to make sure I have a solid grip before the ripcord pull. Usually starts with 2 pulls…but I can feel the compression pressure come out of the exhaust muffler! It clearly produces a pop-pop-pop-pop engine noise that overpowers saws with bigger displacement….I am wondering if that model of saw had a higher compression engine or something special? It just revs better and seems more stronger/stout than the the other saws….curious….

Much thanks!
Alaskan Stihl

 

[MacAttack]

#1: I set the coil - flywheel gap .010 - .012, either works fine.

#2: 10-10 is a bada$$ saw, a real man's saw.

 

[PogoInTheWoods]

Poor man's feeler gauge for setting the air gap is a business card. It's what I use..

 

[Alaskan Stihl]

Just how critical is getting the Gap exactly right? Reason being , is that I also have a Stihl Gap Gauge that is set for a Gap of 0.35. Since it is arch shaped, it would be so easy to install when setting the gap (ergonomically friendly)…problem is that the McCulloch 110 requires a total tear down in case the gap is too much…

I do happen to have a set of feeler gauges….I probably should just use those…just curious if 0.10 vs 0.35 is a significant discrepancy when it has to do with gaps?

 

[PogoInTheWoods]

0.35 is way too wide even for a normal spark plug. A basic business card will work every time at around 0.12 ~ unless it's laminated or extra heavy stock.

Out of curiosity, what is the application for that Stihl gauge?

 

[MacAttack]

A business card is right around .012 and you can find them everywhere

 

[heimannm]

For the coil to flywheel adjustment, there is a noticeable difference in the spark closing it from .010 down to .006". At .035" there will likely be no spark at all. .35 mm is a little over .012" which may be alright, but I prefer to set them right at .010".

Mark

 

[Alaskan Stihl]

I bought the Stihl Gauge as recommended from the Service Manual for my MS-290. I had some hiccups along the way (the freaking Proto torque wrench I purchased ….did not click…even though it was only set at I 1/2 the recommended inch pounds. I was thinking “this is way too much power leverage for only 40-some odd inches ….then STRIP…I twisted out the threads in the cylinder head! Needles to say, I returned that piece of garbage! Anyway, I drilled out the threads and installed a friction lock nut and finished putting that saw together. It works like a brand new saw!

Welp, back to the McCulloch 110. Sounds like business card it is. Maybe double check it with a feeler gauge (certainly do t want to disassemble it all over again to reset the gap)

 

[PogoInTheWoods]

A business card is right around .012 and you can find them everywhere

Duh. My bad. (I hadn't had my second cup of coffee yet. )

The Mac spec is 0.010 ~ 0.015 for the air gap. A well worn business card should come in on the 0.010 side.

 

[Alaskan Stihl]

So it sounds like my Stihl Air Gap Tool might work? It is 0.35mm. When I converted the mm….it comes out to .013. I realize that is a smidge over .012….but close?

 

[PogoInTheWoods]

If Dr. McHeimann says 0.010", then 0.010" is where I'd tend to lean.

 

[Alaskan Stihl]

Yup, agreed. Just checking to see if there was wiggle room.

Final decision is going to use my feeler gauge since it is precise. The saw is relatively new. The parts aren’t worn at much at all. Of the (4) saws that I got from the guy….(3) of them so far has had carburetor issues. My guess is that he ran them a little until they plugged up with sawdust (see pic) then put it on the shelf and bought a néw saw.

Particularly with this Mac 110, I want to make sure I get it right the first time….since the whole saw has to be torn down jut to access the spark plug and carb! Grrrr….

 

[MacAttack]

Ive observed 2 things with the Mini Mac flywheel / coil gaps.

- Any factory-setup Mini Mac or even my SP40 that I've ever worked on, the flywheel gap was about .018". Much greater than the spec.
- the coil laminations aren't even CLOSE to perpendicular to the flywheel, haha. The flywheel gap is always much wider toward the face of the flywheel. I set them at the tightest spot (crank case side).

 

[Manic84]

Well... About that "Screen"...
After using an otoscope to get a closer look and re-examining the MDC from the Mini 30 and that other MDC that I had, the conclusion I've come to is that yes, it is a screen... And just maybe, all MDCs have it.
I will note that the carb/seat has to be somewhat dry, otherwise you'll just see a bubble of fluid and not the screen.

The more I looked at it, the more it reminded me of those plastic looking, main jet screens on some 4-cycle carbs.
It could've been some type of metal mesh, but I'm not so sure. I'm thinking that the screen is integrated somehow into the seat itself.
I tried to get a picture of it, but it was never clear, or came out right. This was a real odd one for me.

One more thing. Pogo, did you see a screen in the MDC on that no-spark Mini you had? I'm very curious about that.
It would be cool if that would prove the existence of this thing. Or it'll bust it and that means it was just a fluke on my end.

 

[MacAttack]

I think I have a disassembled MDC I could check... But man seeing it through the metering seat, must be hard to see with the naked eye??

 

[MacAttack]

Also...I must be getting better at fixing Mini Macs, the MM35 screams. It started in relatively few pulls, just a little tweaking on the carb and it will sit and idle. Good throttle response, and really barks!
The only strange thing was before it started, it had good resistance on the rope, but I couldn't hear the compression pulse out the exhaust. Very unlike my other Minis, if you told me something internally was busted I would have believed it. It was like the exhaust was capped off?
I never did a compression test, but rings and cylinder looked fine. But then the saw fired and once it was running seemed perfect. It starts easily once warm. The saw probably hadn't run in decades... I wonder if the rings were a little stuck?

Here's the 35, and next to my reliable old MM30, the only saw I had for about 20 years!

 

[MacAttack]

Well Manic84 this will make your day... I looked in my disassembled MDC carb and for darn sure it has a stainless mesh screen behind the inlet seat. With some finagling I managed to get a picture. Zoom in on the seat and you can see it pretty clearly. They probably all have them. This carb came out of my Mini Mac 25.