Jug Temp with different arrestor screens and no screen -MS661

[redbull660]

Did 3 cuts for each setup. Let Jug cool to 225F before I started next cuts. New Chains. 36" tsumura bar.


1st up - Stock opening + stock screen - 28.7 28.5 38.3 ( 366 F)

Next up - Stock opening + Wide weave screen - 28.2 28.0 37.2 (359F)

Next up - Stock opening + NO screen - 27.8 27.7 36.9 (348F)

Last - Modded/opened up port + wide screen - 26.5 26.6 35.2 (339 F)

stock screen & wide weave

I know...how does it run with modded muffler with out a screen. Hindsight = 20/20.

Here is the wide weave screen I'm using. http://www.amazon.com/gp/product/B005H3FFXW/ref=oh_details_o00_s00_i00
I wouldn't mind having something with larger weave yet.

 

[Deets066]

I throw the screens out

 

[neely]

I throw the screens out

you dont have any trouble with valve float ? as back pressure will almost be nill

 

[Chainsaw Jim]

you dont have any trouble with valve float ? as back pressure will almost be nill

We're talking about engines without valves. The back pressure comes with the size of the exhaust opening.

 

[Deets066]

Tri-port with no screens, no issues.
Back pressure is overrated, lol

 

[neely]

We're talking about engines without valves. The back pressure comes with the size of the exhaust opening.

ok i understand what your saying now

 

[redoakneck]

No screen, ever worry about a stinking stink bug crawling in the jug, I've taken apart saws and found them behind the flywheel!!! Only reason I keep screens on most of mine, ones without screens get plugs or panty hose

 

[Deets066]

No screen, ever worry about a stinking stink bug crawling in the jug, I've taken apart saws and found them behind the flywheel!!! Only reason I keep screens on most of mine, ones without screens get plugs or panty hose

No, never thought of that
I bet that would make the jug temp rise at least 2.4 degrees after two cuts with stink bugs in there.

 

[redoakneck]

No, never thought of that
I bet that would make the jug temp rise at least 2.4 degrees after two cuts with stink bugs in there.

I think that's why they call it squish???

 

[mdavlee]

Wonder how much cooler a dual port or triple port.

 

[Moparmyway]

I wouldn't mind having something with larger weave yet.

I offered to send you some already ................... you didnt want any

 

[redbull660]

I offered to send you some already ................... you didnt want any

I didn't? Well, I was wrong! Send away! Please!

 

[Moparmyway]

Running low myself now ............... MSC part number is in 3rd picture. I think 2 sheets is like $15

 

[redfin]

Open that the entire way under deflector and then you will really see a difference.

 

[Moparmyway]

Open that the entire way under deflector and then you will really see a difference.

Pics of yours ???

 

[marti384]

My 266 didn't have a screen when I got it. Put it in the shed, the next time I went to use it there was a mouse nest in the muffler, and since the piston was down, there was also part of a nest in the cylinder. All my saws have screens or rags that get stuffed in the muffler before I put them away now.

 

[redfin]

Pics of yours ???

 

[Rx7man]

It's amazing what some slight exhaust restrictions does for heat buildup... I'm familiar with it from diesel engines.. put a bigger flowing turbine housing and big exhaust on it and you can see over 100* temp drop easily.. On my KTM 450, the stainless header pipe would be scorching hot after just a couple blips of the throttle, I uncorked the muffler and it was instantly cooler.

 

[Moparmyway]

View attachment 445276

Mine is just about there ...........
I am running a Max Flow - have you tried that yet ?

So ............ do you think I will see some more from the saw with removing that little bit left in there ?

Looks like I took mine a little further back, and I also altered the final opening on mine ........

 

[big t double]

Weave. I'm not sure how wide this weave is but could you attach it to your saw and see how it affects the heat? Thanks.