Muffler mod - Remove spark arrestor??

[AlexP]

Thanks to all the great advice on this forum I have done my first muffler mod to my very low hour 14 year old Poulan 2800. I opened up the interior baffle holes slightly and added a couple more small holes. I opened up and matched the muffler base to the exhaust port since it was very slightly blocking the port on one side. I also added another exhaust outlet to the opposite side of the muffler and modified the plastic cylinder cover slightly to clear the new muffler opening. It now somewhat resembles one of the Stihl dual port mufflers. A junior version.

When you guys do your muffler mods do you generally then run the saw without the spark arrestor? My saw muffler has a very fine mesh screen which seems like it would be very restrictive. Since it will mostly be doing yard work I will more than likely leave it out. Is there a less restrictive mesh that can be used?

I haven't run it yet because I am waiting on some Mobil Racing 2T oil I just ordered based on advice from here also. I can hardly wait for the oil to get here so I can try the "new improved" saw out.

Two weeks ago my saw hadn't run in years and after rebuilding the carb, replacing all the fuel lines and filter, retuning the carb, etc, the saw was running really well. Now I am doing mods. I think I have caught the chain saw bug from reading too much here. Thank you all for the inspiration and knowledge exchange.

 

[314epw]

screen

It is against the the to cut on state lands without the screen.But since your asking me, I run without the screen.Near started a fire.But with the muffler mod I have smoked some bark!:deadhorse: After a while those screens would clod up(without muffler mods)

 

[Hired Gun]

No screen's for me

 

[Cut4fun]

No baffles and no screens here.

 

[Lakeside53]

A decent screen system has an area many times the outlet size... Harder to engineer with the typical home mods, but that way the restriction of the wires becomes irrelevant.

If the saw is running right with a reasonable mix, the screen won't clog.

Start a forest fire out here with a saw (or a modified quad!), and you'll get a tidy bill... Last one was $6 million.. to a guy running a modified bike...


Just getting caught cutting without a screen can cost as much as an MS660!

 

[fishhuntcutwood]

All of mine have screens except my 200T, which I never have reason to use on state land. Like Andy says, gotta have screens out here.

 

[NWCS]

in all my muffler mods i install Stainless Steel spark screen. while milling with a husky 181 i have indeed started a small fire. exhaust was pointing straight down and caught the fine sawdust on fire. was the second pass on a 30" wide 35ft fir log so there was a good pile built up along the ground. temp was probly 68 and no wind. saw was bone stock other than the removed spark screen (this was years before i even learned about modified saws)

 

[AlexP]

Arrestor screen question

Does anyone sell the stainless screen material or is this just a hardware store type item? The screen in my Poulan 2800 seems like it would be very restrictive and I would definitely like to make it a greater diameter with more surface area if possible.

Also, do the state forestry personnel actually make folks take their mufflers apart to check for screens?

 

[scottr]

Wire cloth

Does anyone sell the stainless screen material or is this just a hardware store type item? The screen in my Poulan 2800 seems like it would be very restrictive and I would definitely like to make it a greater diameter with more surface area if possible.

Also, do the state forestry personnel actually make folks take their mufflers apart to check for screens?

Alex , if you go to mcmaster.com and search wire cloth you'll find plenty of options . Are the outlets for your muffler in the back like the 3400 Poulan ?

 

[rahtreelimbs]

Does anyone sell the stainless screen material or is this just a hardware store type item? The screen in my Poulan 2800 seems like it would be very restrictive and I would definitely like to make it a greater diameter with more surface area if possible.

Also, do the state forestry personnel actually make folks take their mufflers apart to check for screens?

Pick up a stainless steel strainer at the grocery store!

 

[fishhuntcutwood]

Also, do the state forestry personnel actually make folks take their mufflers apart to check for screens?

All of my saws at least you can see them without taking anything apart, but yes, they are serious about it.

 

[Kneejerk Bombas]

Don't forget the spark arrester screen is also a filter to keep stuff out of your engine. It's not like a car where the muffler is 15 feet long, it's only a couple inches to a port directly into the cylinder.
If you feel the screen is blocking airflow, just make the exit hole a little bigger to compensate. Removing the screen to improve airflow is almost like removing the air cleaner to improve airflow.
Think about it like this, did you ever see a guy take off the intake boot on a motor and carefully stick a clean rag into the opening so no foreign object could fall into the opening while he worked? Now imagine the same guy having his saw bouncing around in the back of his truck, out in the woods, maybe on a gravel driveway, all with the same type of port he so carefully covered in the shop, sitting wide open. It doesn't make sense.

 

[AlexP]

Ok. Y'all have convinced me to keep the screen in.

rahtreelimbs, The idea of the stainless strainer is a good one. I am sure I can rig up something more to my liking with that strainer material.

Scottr , I totally forgot about Mcmaster Carr and I am sure they would have what I need. The muffler outlets on the 2800 are on each side of the muffler about midway where the two halves meet. The exhaust actually exits to the front half of the muffler, goes up and down thru the arrestor and comes back thru the perforated baffle plate between both muffler halves before going out the exhaust ports. The muffler came with one factory port. Now it has two.

Mike, I never thought that the arrestor would serve the purpose of keeping stuff out of the cylinder also but it makes sense to me.

I can't wait to try this saw out this weekend. Thank you all for the replies.

Alex