2100CD runs but surges/dies in the cut

[chunez]

I scored a cheap 2100cd locally as non running, noticed that the spark plug wire was melted and arcing on the cylinder and taped it up and she started right up and ran! I set the jets to the factory positions and started to tune it. When I do a small 12" dia test cut it revs up but then has a hesitation before finally going to max RPM. It will run fine but halfway through the cut it will kind of surge and crap out. If I keep holding the trigger, it will eventually rev up again and cut but then does the same thing and craps out again. It like its being starved of fuel in the cut. Already swapped in a new large husky stone fuel filter and checked the microscreen on the carb. Carb looked brand new and diaphragm felt nice and flexible but I will probably get a kit ordered anyways. The caps were leaking so I swapped on some flippy caps. Cant remember if they have a built in vent or not. There is a (probably not stock) tank vent hose sticking up into the air filter area with a small BB on the end that releases pressure when I push on it. The tank was apparently really pressurized when I pulled the carb off because it shot a ton of gas out so fast it was like foaming. I'm thinking it has something to do with the tank vent. Shouldn't a check valve release pressure when pushed from the inlet not the outlet? Maybe I just have to flip this thing around?

Its an old one with the femsa ignition, I already picked up a used SEM flywheel and will buy a new SEM coil when it finally fails. I noticed new melt marks on the spark plug wire after I fixed it so I may not have positioned it correctly. I still have the wire retainer on the cyl but what is the proper routing to keep it from getting melted again?

AV mounts seem serviceable. Any other things to look out for on these legendary saws?

 

[NSEric]

I know nothing about that model saw but echo tank vents work great on any tank with a hose on the vent.
I have a 6 pack of them on hand for any saw that has a vent issue.

 

[chunez]

I know nothing about that model saw but echo tank vents work great on any tank with a hose on the vent.
I have a 6 pack of them on hand for any saw that has a vent issue.

Funny, just read that in another thread and was already on my way to pick one up. I have the old one separated from the line but cannot get a good angle on this thing to press it on. Do you have to remove the vent hose from the saw to press on the vent cap?

 

[NSEric]

Funny, just read that in another thread and was already on my way to pick one up. I have the old one separated from the line but cannot get a good angle on this thing to press it on. Do you have to remove the vent hose from the saw to press on the vent cap?

If you can get a hold of the line you can just push the echo vent into it.

 

[Lightning Performance]

How old is the fuel?
What was today's temperature there?
Did you get it warmed up?

 

[chunez]

How old is the fuel?
What was today's temperature there?
Did you get it warmed up?

2 weeks old, premium non ethanol. Yes it was warmed up. 55 F

 

[chunez]

If you can get a hold of the line you can just push the echo vent into it.

Definitely not happening. I’ll need to pull the line to get any leverage on it. You can see the vent recessed in the corner in a few pics

 

[singinwoodwackr]

I scored a cheap 2100cd locally as non running, noticed that the spark plug wire was melted and arcing on the cylinder and taped it up and she started right up and ran! I set the jets to the factory positions and started to tune it. When I do a small 12" dia test cut it revs up but then has a hesitation before finally going to max RPM. It will run fine but halfway through the cut it will kind of surge and crap out. If I keep holding the trigger, it will eventually rev up again and cut but then does the same thing and craps out again. It like its being starved of fuel in the cut. Already swapped in a new large husky stone fuel filter and checked the microscreen on the carb. Carb looked brand new and diaphragm felt nice and flexible but I will probably get a kit ordered anyways. The caps were leaking so I swapped on some flippy caps. Cant remember if they have a built in vent or not. There is a (probably not stock) tank vent hose sticking up into the air filter area with a small BB on the end that releases pressure when I push on it. The tank was apparently really pressurized when I pulled the carb off because it shot a ton of gas out so fast it was like foaming. I'm thinking it has something to do with the tank vent. Shouldn't a check valve release pressure when pushed from the inlet not the outlet? Maybe I just have to flip this thing around?

Its an old one with the femsa ignition, I already picked up a used SEM flywheel and will buy a new SEM coil when it finally fails. I noticed new melt marks on the spark plug wire after I fixed it so I may not have positioned it correctly. I still have the wire retainer on the cyl but what is the proper routing to keep it from getting melted again?

AV mounts seem serviceable. Any other things to look out for on these legendary saws?
View attachment 1160319View attachment 1160320View attachment 1160321View attachment 1160322View attachment 1160323View attachment 1160324View attachment 1160325

Wow, that's in great shape!

 

[chunez]

Wow, that's in great shape!

Would it be a crime to mill with this?

 

[singinwoodwackr]

Would it be a crime to mill with this?

No. But you need to find and fix the air leak first

 

[Lightning Performance]

Would it be a crime to mill with this?

Yeah right. It's a tool not a toy.

 

[aokpops]

A bog down is about always a fuel delivery problem. With man or machine you will not out run your heart and lungs. A engine will not produce good power with lack of fuel . I went from a 3mile run to maybe half mile I had the widow maker. After surgery the run output is way higher.

 

[chunez]

Ok definitely not a vent issue. Hopefully the carb kit and fuel line take care of it. Don’t want to split the case!

Think this will pull a 42” skip rip .404? I have the parts to swap over to 42” 3/8 skip rip as well

 

[singinwoodwackr]

Ok definitely not a vent issue. Hopefully the carb kit and fuel line take care of it. Don’t want to split the case!

Think this will pull a 42” skip rip .404? I have the parts to swap over to 42” 3/8 skip rip as well

It will pull a 60

 

[Gord404]

the tank vent is on the top of your tank left hand side in the carb area if it's still there or someone might have just plugged it up

 

[chunez]

the tank vent is on the top of your tank left hand side in the carb area if it's still there or someone might have just plugged it up

You can see it in the pictures. Is that aluminum insert the stock vent? I know it’s missing the foam cap thing

 

[Gord404]

well been a while but if it's directly on tha tank that would be it- might be plugged up with crap- will look at my 2100 later

 

[singinwoodwackr]

the tank vent is on the top of your tank left hand side in the carb area if it's still there or someone might have just plugged it up

Both tanks I have are plugged