O&R saw that won’t start

[Csaw 4]

I have an old saw model 20 A 274 that has been sitting for 40 years. I tried to get it going but with no luck. First it had no spark. The condenser tested good. I cleaned up the points a little and got spark. I threw a little mixed gas in the spark plug hole but it won’t pop. I replaced the spark plug as a test but no luck. Switch is on otherwise I wouldn’t have spark.
 

I took off the muffler and the piston looks good at first glance, no lines.
 

1) is the champion cj6 that was in it the right plug?

2) I’m sure crank seals are shot and who knows what else but what else can I try just to see if it it will come alive?

 

Thanks

[Wallfish 698]

The bigger 20A engines aren't necessarily my thing but you should have a nice snapping blue spark. A weak orange spark may jump the plug gap out of the engine but maybe not under compression.

Even with bad crank seals it should still pop.

Just thinking out loud

Timing is accomplished by the key in the flywheel so maybe verify the key

maybe another condenser

Cj6 plug sounds right but I'm not 100% sure. I can check an engine to see what's in it

Cranks seals can swelled with DOT3 brake fluid or spray carb cleaner

20A engines have a compression release for starting

 

[Csaw 4]

The existing Champion CJ6 sparkplug did have a strong, blue spark but replacing it with a new Autolite 254 didn't fix anything. But if you could confirm what you are using, that would be helpful.

 

I confirmed the key was in the crank shaft slot and the fly wheel slot was on the key. I'm pretty sure I remember there only being a single key/slot on the shaft and flywheel so not like it's in the wrong one.

 

With my ohm meter, I could see when I connected it to the condenser that the condenser would charge. I could also see the condenser discharging as expected so I would think that means the condenser is good, but maybe not? If I"m seeing a strong spark could the condenser still be bad?

 

Thinking about compression, it is a little hard/awkward to pull over but maybe that is just because the pull cord is goofy off the back of the recoil and not at the top where I'm used to it with modern saws.

 

 

 

 

[CNew 404]

Van you tell if you’re getting fuel from the tank to the carb? I have one of these saws (not the Ford version) and when I dug into it I found that the fuel filter and line in the tank were completely clogged and rotten. One of those black levers on top should be a choke too. There’s also a funky plastic reed valve with a rubber seal where it mates to the carburetor. If that think is rock hard or the plastic flaps are cracked it’ll let air in.

[Csaw 4]

I’ll have to check that. Would think it would still pop though when I put fuel straight in the plug hole.

[CNew 404]

Good point, direct fuel and no pop while there is spark is odd. If you decide you need a new condenser I think this is the right one for the 20A.

https://www.ebay.com/itm/193427935921?hash=item2d093412b1:g:HSUAAOSwwnpemjfc

[Csaw 4]

Have you seen the reed valves for sale anywhere?

[CNew 404]

New: https://www.ebay.com/itm/193890122548?hash=item2d24c07b34:g:JyQAAOSwvHFgJs3X

 

Used:  https://www.ebay.com/itm/363531145384?hash=item54a42510a8:g:sJIAAOSwgwBhM5kV

[Csaw 4]

Hmm…I see a gap in mine on one side which may be a problem.

[Csaw 4]

To get the fuel line off, does the fly wheel need to come off (again) in order to get that side wall plate off that is up next to the fuel tank?

[CNew 404]

Hmmm, I don’t recall. I’ll have to dig out the saw and study that a little.

[Csaw 4]

If anyone also has crank seal # or sizes that would be helpful too. Starting to run out of any other ideas.

 

looks like 200041 is the pn for the crank shaft seals.

 

https://myoldmachine.com/applications/core/interface/file/attachment.php?id=35503

 

 

Edited December 5, 2021 by Csaw

[Fishnuts2 22]

On 12/2/2021 at 5:35 PM, Csaw said:

Hmm…I see a gap in mine on one side which may be a problem.

Flip the petal over.  I've pulled on the starter cord too many times to no avail, on an engine with a broken or leaky reed valve.  I'm a little smarter now!

[Csaw 4]

Replaced the 2 crank shaft seals and it now fires.  Size are 13x22x5 if anyone needs to order replacements.

[CNew 404]

Where did you find a source for the seals?

[Csaw 4]

13 x 22 x 5

 

https://www.aliexpress.com/item/1005003107101680.html

 

But this would work

 

https://www.ereplacementparts.com/oil-seal-13x22x5-p-1443576.html

 

or 

 

https://www.jackssmallengines.com/jacks-parts-lookup/part/honda/91204ke8003

[Csaw 4]

After replacing the seals, it will fire now only if I put gas in the carb. I took the carb apart and everything was bone dry and the diaphragm was hard. The carb is model hdc-11. I ordered a kdc-10 kit and now too much gas, floods. I noticed that the button on this new diphragm is larger which causes the meter level to be pushed in, unseating the needle. See photo, new on the left, original on the right. For anyone else that has bought one of these kits, how large was the diaphragm button?

Edited April 4, 2022 by Csaw

[Fishnuts2 22]

I had the same thing happen to a carb I was rebuilding.  Flooded all the time until i filed the button down to the same height as the original.  It's aluminum and won't take very long to fix it .  Make sure the gasket is first on the carb base, then the metering diaphragm.  

[Csaw 4]

On 4/4/2022 at 8:44 PM, Fishnuts2 said:

I had the same thing happen to a carb I was rebuilding.  Flooded all the time until i filed the button down to the same height as the original.  It's aluminum and won't take very long to fix it .  Make sure the gasket is first on the carb base, then the metering diaphragm.  

That fixed it. thank you. Now it's alive!   First time it has ran in 50 years.

 

[Csaw 4]

Can someone share what their air filter looks like for their Orline 20A saw?  Mine is missing and I need to make something.

[CNew 404]

https://www.ebay.com/itm/363286493021?hash=item54958ff75d:g:jPsAAOSw55NgIWM2
 

should be like this one I believe. I’ll check my saw when I get home

[Csaw 4]

1 hour ago, CNew said:

https://www.ebay.com/itm/363286493021?hash=item54958ff75d:g:jPsAAOSw55NgIWM2
 

should be like this one I believe. I’ll check my saw when I get home

thanks.  And that filter is just sandwiched between the 2 plates I assume?

 

[CNew 404]

Yes, as far as I know.  I also added a piece of green air filter foam to fill the gap.

 

[Csaw 4]

thanks for the photos.

I didn't have the carb to air cleaner seal so I 3d printed one out of TPU.  Here's the STL file if anyone needs it.orline air filter gasket.stl

[CNew 404]

Very cool, let us know how the 3DP works. Did you go with Laser sintered powder technology?