Tricks for starting large old chainsaw

[Roly]

Gentlemen,
I am Roly from Puget Sound in Washington State. I have a McCulloch I-40 with .440 chain and a 24" bar, from the late 1950's, that I last ran several years ago. I was told that it can put out nearly 5 horsepower on a good day. It was hard to start then, and won't start now (and I'm 61 now). I put in fresh gas, checked the filters and fuel line, and plug. It has such good compression that it is a beast to pull. The instruction indicates, of course, that the throttle is opened and choke on to start. Thing is, there is no slide button to hold the throttle open, I only have 2 hands, and need to hold the thing down with my foot in the handle and right hand on top to get enough force on the cord with my left hand to turn it.

How did I ever start it before, if I cannot hold the throttle open with one hand and pull the cord with the other? I can do this with my "newer" saw, a Stihl 130AV, no problem. It has a slide button for the throttle.

How the heck do you do this? I was not 8 feet tall and covered with muscles 5 years ago when I last used this thing, but that is what seems to be called for.

Thanks, Roly

 

[Henry G.]

I step on top of my SP81 with my left foot, put the choke on, hold the throttle wide open with left hand, pull start with right hand. 3rd or fourth pull it pops and dies. Then choke off, wide open throttle and it will start first pull.

 

[sawbones]

you need to cheat.. them old saws are a bugger to start even if everything works good. I would pull the airfilter and put some mixed gas in a squirt can and give it a shot down the plug hole or the carb.

with the squirt it should fire. then if its pulling gas ok you can grab the throttle

 

[056kid]

nudge the cord untill you have the piston just about to stroke.

As for the method of starting, one hand throttle, other hand cord is really the best..

 

[blackoak]

you need to cheat.. them old saws are a bugger to start even if everything works good. I would pull the airfilter and put some mixed gas in a squirt can and give it a shot down the plug hole or the carb.

with the squirt it should fire. then if its pulling gas ok you can grab the throttle

+1. My little plastic squeeze bottle of mix is one of my most used tools when working on old, and sometimes newer saws.

 

[TraditionalTool]

I was told that it can put out nearly 5 horsepower on a good day.

Wow, that's a lot...I don't know about a good day, but this Dolmar 7900 appears to provide 1 HP...

 

[stinkbait]

On the old macs like that I put my right foot in the rear handle loop and curl the end of my foot up till it depresses the throttle. Then I pull the rope with my right hand with my left hand on the front handle.

 

[alpinecrick]

+1. My little plastic squeeze bottle of mix is one of my most used tools when working on old, and sometimes newer saws.

Me too.......



Casey

 

[Freehand]

Wow, that's a lot...I don't know about a good day, but this Dolmar 7900 appears to provide 1 HP...

Less if you're rubbing your gonads on it.............:hmm3grin2orange::hmm3grin2orange::hmm3grin2orange:

 

[Roly]

Thanks for the answers, but

do some of you guys have the pull cord on the right side of your saw? How else you gonna pull the thing with your right hand?

My cord is on the left side, looking down at it with the bar away in front....

I'll get me a little squirt bottle, and maybe make a clip of some sort to hold the throttle open..
Thanks for the clues
Roly

 

[Knuckles]

do some of you guys have the pull cord on the right side of your saw? How else you gonna pull the thing with your right hand?

My cord is on the left side, looking down at it with the bar away in front....

I'll get me a little squirt bottle, and maybe make a clip of some sort to hold the throttle open..
Thanks for the clues
Roly

huh???? Stand on the cord side of the saw, reach down with your RIGHT hand and give it a good tug :lifter:

Am I missing something here?

 

[dwesty]

Gentlemen,
I am Roly from Puget Sound in Washington State. I have a McCulloch I-40 with .440 chain and a 24" bar, from the late 1950's, that I last ran several years ago. I was told that it can put out nearly 5 horsepower on a good day. It was hard to start then, and won't start now (and I'm 61 now). I put in fresh gas, checked the filters and fuel line, and plug. It has such good compression that it is a beast to pull.

How the heck do you do this?

Thanks, Roly

I couldn't sell my pile of saws, so I've been making them run. And I've learned a number of things related to the original poster's question ...

1. If you have trouble pulling over a saw that's sat for a long time it's probably got oil/gum residue in the rings, giving you VERY high compression and a lot of drag. Pull the spark plug and squirt some brake cleaner in the cylinder. That should loosen up all the sludge that's accumulated and give you the benefit of the loose rings in a 50 year old saw.

2. There's a simple trick for holding the throttle open on an old McCulloch (or just about anything else, for that matter) .... go to the hardware store and buy a 5-pack of little Velcro straps ... about $4. Wrap one around the throttle trigger, and there you go .... starting your monster saw is back to a 2-handed (instead of 3-handed) exercise.

have fun.

dwesty.

 

[user 122190]

huh???? Stand on the cord side of the saw, reach down with your RIGHT hand and give it a good tug :lifter:

Am I missing something here?

Sounds right to me, and my cord is made of rope (flexible) and I can pull it with my right hand by reaching across the saw. And won't a piece of tape hold the throttle open?

Is there a picture of this saw coming to explain this strange saw and the complexities it raises.

 

[Bob Hedgecutter]

Sounds right to me, and my cord is make of rope (flexible) and I can pull it with my right hand by reaching across the saw. And won't a piece of tape hold the throttle open?

Is there a picture of this saw coming to explain this strange saw and the complexities it raises.

Maybe they did not have digital cameras way back in 2009?

A sliding zip tie on the handle will work to hold the throttle open, push it back when the saw is running, but it is still there when needing to start it next.

 

[user 122190]

Good catch. A 10yo thread. Hopefully the OP has got it all figured out.

 

[Huskybill]

2009 ooops wasn’t me this time lol

I have a 8” bench I put the saw on it, stick my foot in the rear handle, choke on throttle on, pull it. But first I’d make sure it’s not flooded.

 

[SEAM]

Some old saws you need to practically flood to have a chance to start them... Turn switch OFF, put choke ON and pull until the engine will turn a couple of rotations without resistance. Turn switch ON, pull cord a couple of times, then put choke OFF to start - works with most saws except for Stihl after late 1970s... Squirting a little "cheating" gas into the carb bore will abbreviate the starting procedure...

This won't really help if you have an ignition timing problem, though...

PS: Just remembered - if there is enough room on the starter rope pulley adding a turn will make starting a lot easier!

 

[Okie]

Noticed this OLD thread has been revived.

How I start my old Mac's (1-40's, 50's, 250's, especially the ones coming out of storage. Get a little squirt bottle of mixed gas, get a 6 inch piece of #10 solid copper electric wire from a piece of romex electrical wire, wrap the single solid wire around the throttle trigger snug enough to hold the throttle open but it can be slid down and off the throttle trigger when saw starts running. (Just leave the wire wrapped around the handle for next time.

You will need to usually tie the throttle wide open for start even when the saw is warm but especially true when the saw is cold on these models. Prime the saw (with a spoonful of mixed gas through the muffle if it's the cast iron direct shot into cylinder muffler. This eliminates removing the air box cover and priming the carb throat. My shoe is big enough that I can stick my toe in the throttle area and hold it down while cranking. Them saws most generally want a wide open throttle for starting. Try not to flood the saw when it's cold, if you suspect it's flooded just keep cranking with the throttle wide open and if after about 10 pulls it don't pop, it need another small prime.

Apply full choke and crank until it start popping and trying to run, remove choke and prime again, leaving choke off, sometimes they have to be primed several times so as it will momentarily runs for few seconds several times before they will take hold and run when coming out of storage.. If priming through the carb throat hold the saw up so gas runs inside the cylinder.
Place the saw on the ground and place foot inside throttle handle area to hold the big heavy saw down.
You need to be stout and these saws are not made to be operated by Pansies and Nancy's.

If the saw makes you hurt after using, it's time to sell and get a lighter saw.

Mac collectors will buy one for parts, etc. (they are heavy and shipping costly and this hurts the selling price of a complete saw) Individual good used parts sell good on flea bay.

At least 3 different type carbs were used on those, so you have to be careful when shopping for kits.

Good luck too you and hope it's not hurt you too bad yet.

 

[Bob Hedgecutter]

You need to be stout and these saws are not made to be operated by Pansies and Nancy's.

If the saw makes you hurt after using, it's time to sell and get a lighter saw.

Possibly the best thing I have read on here in ages!!!!!
All MS 660 owners should also take note!

 

[2broke2ride]

Lay the bar over a log, right hand on the pistol grip/throttle, left hand on the pull start and pull like ya mean it.
That is how I was taught to start all saws, I catch flack for it because apparently it isnt considered safe, but it works for me and it is the only way I know to start these big old saws without throttle locks.
And I'm sorry, but there is no way in hell I'm going to wire the throttle open on a saw without a chain brake. Something about a saw running wide open sitting on the ground seems much more unsafe to me than my way.