Need help drilling holes muffler mod
- Thread starter Dommm
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Does it come apart?
What is inside?
Where is existing outlet and how does that compare to ex port area?
Can You adjust the carb on this saw ( Hi/Lo)?
What is inside?
Where is existing outlet and how does that compare to ex port area?
Can You adjust the carb on this saw ( Hi/Lo)?
Check your messages .
Oops, I though i was gonna drill hole directly into that
Have you run this saw without the spark arrestor screen ?
Your muffler has a diffuser with a open area of 0.6491 square inch . The muffler outlet restricted is 0.199 square inch. Unrestricted muffler outlet is 0.398 square inch . There is no need to drill this muffler . Run it without the spark arrestor screen, yes it will be louder but it might be tolerable .
Just pull that front cover that the nut is holding on, you can pull the screen and can make the hole under there a little larger, you can also make the opening in that cover larger.
smokey7
jack of a lot ace of a few
I usuly just slot the holes wider on those under that cover. Be sure to have the spline carb tool tho. They run a whole lot better after its tuned well.
I took the baffle out of mine and the spark screen then made those holes behind that front plate bigger then put the plate back on. Tuned it up and it made a big difference along with a sharp non safety chain.
motoguy
ArboristSite Member
I have the muffler from my 4218 off in front of me right now. I've found several descriptions of modding the muffler, but it looks like most of the photos are old/gone. Here is what I've read about:
1) dremel a "flap" (2nd exhaust port) on the side.
2) open up the stock slots, remove screen, otherwise stock
3) open up the stock slots, remove stock screen, place washers to lift/space the diffuser farther off (and bent/open it's outlet a little bit)
4) same as above, but cut/pry/remove the access tubes for the mount bolts.
I do not plan on porting/etc this saw. Just a muffler mod and retune. That being said, what's the "best" way to go about modding this muffler? I personally would place an emphasis on maintaining a stock appearance, so I only want to do #1 if it's just hands-down better.
1) dremel a "flap" (2nd exhaust port) on the side.
2) open up the stock slots, remove screen, otherwise stock
3) open up the stock slots, remove stock screen, place washers to lift/space the diffuser farther off (and bent/open it's outlet a little bit)
4) same as above, but cut/pry/remove the access tubes for the mount bolts.
I do not plan on porting/etc this saw. Just a muffler mod and retune. That being said, what's the "best" way to go about modding this muffler? I personally would place an emphasis on maintaining a stock appearance, so I only want to do #1 if it's just hands-down better.
Bobby Kirbos
Scrounger of Cellulose Based BTUs
Here's what I did on my PP3516:.
I should have taken pictures. Sorry.
- The 2 "studs" that go through the muffler for the screws - drill a single 1/4" hole in the side of each of them about 1/2 of the way toward the front (the open end). File the outside of the "studs" so they will fit back into the muffler. When you reassemble the muffler, make sure that these holes point to the inside of the muffler toward the exhaust port.
"Resistance" (static pressure as the HVAC nerds know it) is a function of the size of the opening and the volume of gas that is being pushed through that opening. By drilling out the "studs", you are allowing exhaust gasses to escape through them, thus lowering the amount of gas that is going through the actual muffler.
- Open the slots on the front of the muffler to 2x their width - so they end up about 1/4" tall and 3/4" wide. (Obviously, this allows gasses to escape from the muffler more quickly.)
- Remove the junk that is behind the front cover and replace the cover with just a washer under it. (More resistance removal.)
- Retune and enjoy.
I should have taken pictures. Sorry.
Motoguy, check your private messages .
motoguy
ArboristSite Member
Thanks guys. Here is what I ended up doing:
1) removed spark screen
2) dremeled stock slots open further. Kept original length, opened them up until were flush with the baffle plate (or close). About 1/4", as mentioned above.
3) pulled the bolt access tubes, and drilled holes per Bobby's message above. When reinstalling the tubes, I faced the (freshly drilled) holes towards the the inside (towards the baffle plate mounting bolt and/or exhaust port)
4) The gap between the baffle plate and the exhaust body would have bothered me, so I cut a spacer from some spare 18ga material I had
5) I also took a screwdriver and pried open the baffle plate exit a bit.
1) removed spark screen
2) dremeled stock slots open further. Kept original length, opened them up until were flush with the baffle plate (or close). About 1/4", as mentioned above.
3) pulled the bolt access tubes, and drilled holes per Bobby's message above. When reinstalling the tubes, I faced the (freshly drilled) holes towards the the inside (towards the baffle plate mounting bolt and/or exhaust port)
4) The gap between the baffle plate and the exhaust body would have bothered me, so I cut a spacer from some spare 18ga material I had
5) I also took a screwdriver and pried open the baffle plate exit a bit.
Attachments
The muffler should be the first thing you attack after buying a new saw....
EPA wants us to have Girly saws.
EPA wants us to have Girly saws.
motoguy
ArboristSite Member
I've got Echo cs-501p and cs-620pw on the way. Reports are that both of these saws are transformed by a simple muffler mod and retune. I'm looking forward to that.
Sent from my SM-G955U using Tapatalk
Yes very simple, just remove the spark arrester cover and remove restrictor tube and with a Dremel, open up the cover...done.
Basic ‘flap’ mod. Ten minutes with a cutoff disc in a Dremel.
Adjustable with pliers. [emoji106]
Basic ‘flap’ mod. Ten minutes with a cutoff disc in a Dremel.
Adjustable with pliers. [emoji106]
Did you close the two rear outlets ?
sunfish
Fish Head
Easy, no holes to drill.
No. What for?
