I have a McCullough Mac 10-10A chain saw that is at least 40 years old.

Saw will not run.

Changed out oldvfuel with new fuel. Spark plug is getting plenty of fire. Gas is getting to carburator (can see it with teh air cleaner off when I try to start it). Any suggestions/recomendations (ither than getting a new saw?)

Thanks

I'm not much good at 2 cycle engines, but besides spark and fuel you need air. Could the air flow be restricted - dirty filter, etc.
If you've already checked this, well - nevermind.

3 things needed, air, spark & fuel-you have two out of three- you might have a clogged filter.
BUt I'm a lawyer, I don't profess to be a chain saw master. (well I DO , but I don't carry then official endorsement on my operators liscense-too much for liability insurance )

....and I thought I keep stuff a long time....

You can buy a new baby Stihl for less than two bones which will be equiped with an electronic ignition, unlike your Mac 10, rest it's soul. You'll be a happy camper. I own a pre-electronic ignition Stihl which still runs, but I always use one of the electronic ignition jobs as they start and run soooo much better.

Brian~

Go for the new saw, my grandpa had the same saw and the same problem every time he tried to use it...must've taken ten years off of him!

I believe you have to completely take all of the yeller plastic off to access the carburetor. It will have a rubber diaphragm that needs to be replaced. As previously stated change the fuel filter...
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It is within the realm of belief that your crankcase/crankshaft seals leak. I rather doubt that it has seen that much action.

Those little turds are fun to work on. It's a classic and will provide you w/many tales to tell. I'd try 15 bucks for a couple of parts to have a shot @ it up n runnin'...

LTC,
When she was still running, was she running "fat", as in with a fair amount of smoke? Sometimes, the muffler or spark arrestor grids can become plugged with coal. Nothin' out, means little can come in. After checking that, time to start looking into the carburetor.
Good Luck, tell us what you find!

It is getting fuel, can see it in the carburator.

It is letting exhaust out of the muffler, so I do not think it is clogged up.

This wsaw was one my father used , and the one I learned how to cut trees with. When it runs, it is a fine saw.

Maybe I'll have to investigate the carbutor diaphgram and see if that is the problem.

I've had the same problem a few times ,and its always the spark arrester screen. Remove the muffler, discard the screen (don't replace) and reassemble. You will not harm the unit in any way, and it should solve the problem.

You will be astounded how much "finer" a new Stihl, Husky, or Jonsered will be...most shops around here let you cut a log or two before buying...give it a try!

Did you squirt a little gas in the carb? Even if it's getting gas from the tank I always pour 1/2 oz or so directly in the carb. Usually works for me.

I pulled the screen off of my blue Homelite Super XL-AO farm saw. Came w/16" bar and I put a 20" on. My dad wouldn't let anyone, save me, use ole blue. Picked 'er up new in the early 60's. Ya know AO stands for automatic oiler. Could life get any easier? Heavy and vibrates, yet not like the Sears front tined tiller. When ya blipped the trigger there was no mistaking the bark of 57cc of heavy metal cuttin' machine. No whiney chain-brake or wimpy safety chains. Hang on, pour the coal to 'er and watch those big wood chips fly...
I put a set of rings in 15-20 years ago.

Pull the spark plug and squirt or pour a small amount of fuel into the cylinder. Start with about a half oz. of fuel. Sometimes from sitting the carb is gummed up and things stick or dry out. If you can get it to fire up you should be fine. Sometimes it takes a few tries Sounds like you may need a carb rebuild.
Good Luck
Update
I'll give you a little better description on the how to's

Pour or squirt about a half oz. of fuel mix through sparkplug hole, screw in sparkplug and give it a pull.
Do not have it in the choke position on this attempt at starting.
If it runs for a while then dies you may have a fuel pick up problem (carb or fuel line), repeat procedure one or two more times to give the fuel in the tank to make it's way to the carb.

Idiots guide to compression

With sparkplug firmly seated, gently lift chainsaw off the ground using only the starter handle. If the chainsaw drops gradually or doesn't drop down the chord at all it should be fine. If the chainsaw drops down the pull chord quickly (2 sec or less) it is a compression problem.

If the saw does start but revs up even though the throttle is not held, you probably have an air leak or fuel delivery problem.

This message has been edited. Last edited by: buckwheat01,

quote:

Originally posted by buckwheat01:
Pull the spark plug and squirt a small amount of fuel into the cylinder.

Dang...and I had a good joke all lined up until you added "of fuel"....

Brian~

M28
I had a few chain saws that I would have liked to p*ss on.