dolmar PS-421 mods

[damifino]

The exhaust DOES touch it the exhaust port is on the outter cover after you pull the middle plate and CAT the exhaust goes directly out the cover through the exhaust port instead of through the CAT and then out the exhaust port.

When you pull the middle plate the CAT is attached to its gonna be all bent from prying it out.

Basically all you're doing is gutting the internal part of the outside cover so all it is is a cover with the exhaust port.

I know the exhaust does touch the exhaust port on outer plate but only as it is funneled past by the exhaust port of the middle plate. So you are saying still use the middle plate(with cat removed) and the original outer plate?

 

[KenJax Tree]

Original outer plate. Without then CAT there is no purpose for the middle plate.

 

[damifino]

I Ieft the gills in mine but the CAT is gone. It runs much cooler with the CAT out.

Thats what you do. The plate the CAT in on is tack welded into the cover. Drill the tack welds and the plate falls right out and put the cover back on. You can grind out the gills on the outlet too if want.

This is a 350 but the 421 is the same.
http://www.arboristsite.com/community/threads/dolmar-350-muffler-mod.248809/

Original outer plate. Without then CAT there is no purpose for the middle plate.

I am not following then. In the above quotes you have removed cat but still used middle plate(with cat removed). Now you say without the cat there is no purpose for middle plate. I appreciate your input, I must be missing something.

 

[KenJax Tree]

I am not following then. In the above quotes you have removed cat but still used middle plate(with cat removed). Now you say without the cat there is no purpose for middle plate. I appreciate your input, I must be missing something.

You're missing it. Left the gills in meaning the gills on the outter cover outlet. in order for the CAT to come out so does the whole middle plate and it must be pulled or pryed out so its gonna be all bent up.

Look at the pictures in the link in my quote you posted

 

[CoreyB]

I am not following then. In the above quotes you have removed cat but still used middle plate(with cat removed). Now you say without the cat there is no purpose for middle plate. I appreciate your input, I must be missing something.

You and I are on the same page lol

 

[CoreyB]

As soon as I get one I will do a YouTube video lol I am a hands on learner anyways.

 

[KenJax Tree]

Ok this is the inside of the outer cover after removing it from the saw with the CAT plate intact.

This is showing how the middle plate with the CAT separates from the cover after the welds are drilled

This is the middle plate with the CAT being pulled out of the outside cover

This is the outside cover after the middle plate and CAT was removed. See the gills i was referring to?

Here is the cover put back on without the CAT and middle plate inside

 

[damifino]

You and I are on the same page lol

Thanks Corey, thought my mind was slipping(well...it is). Could there be two different mufflers?

 

[KenJax Tree]

Here is the part that stays on when the outside cover is taken off

 

[KenJax Tree]

Thanks Corey, thought my mind was slipping(well...it is). Could there be two different mufflers?

Those pictures are of a 351 muffler but the 421 is done the exact same way.

 

[damifino]

KenJax I think I am seeing it. You are calling the "outer plate" the outer plate of the middle/with cat plate. I was referring to the outer plate as the very utmost outer plate.

 

[KenJax Tree]

I guess[emoji1]. But you see how it comes apart now?

 

[damifino]

So my original question still remains.... after I remove the cat from the middle section I want to use the remaining middle section(with cat removed) as my outer most piece of the muffler and discard the original outer most piece. So now the muffler becomes a 2 piece empty can. You loose a couple of ounces(not that anyone on this site cares about the weight of a chainsaw) but you also loose another piece of the muffler that could hold heat. Is there any reason why I shouldn't do this.

 

[CoreyB]

So my original question still remains.... after I remove the cat from the middle section I want to use the remaining middle section(with cat removed) as my outer most piece of the muffler and discard the original outer most piece. So now the muffler becomes a 2 piece empty can. You loose a couple of ounces(not that anyone on this site cares about the weight of a chainsaw) but you also loose another piece of the muffler that could hold heat. Is there any reason why I shouldn't do this.

I just took a 421 muffler apart and other then looks I see no need for the outside plate. And other then the hole being very large don't see why a guy couldn't just get rid of the middle section without any grinding.

 

[CoreyB]

Here ya go?

Other then cosmetics I see no reason for the outside plate.

 

[CoreyB]

Anybody want to see a before and after video of a brand new 421?

 

[rburg]

What chain is on your 421?

 

[CoreyB]

What chain is on your 421?

On mine is just some Oregon vxl for now. I want to order some Stihl ps

 

[rburg]

I think you will like the PS chain.

 

[KenJax Tree]

I've ordered PS chain from this guy. He takes a lot of crap for claiming his sprockets allow you to run a 28" on a MS 192 but i've had good service buying chain.

http://m.ebay.com/itm/STIHL-3-8-Pitch-PS-RACING-CHAIN-16-inch-Bar-56-drivers-full-chisel-050-gauge-/271759833210?_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20150519202348%26meid%3D2b0ca6526a82400b8ba661bdbc7ade3f%26pid%3D100408%26rk%3D3%26rkt%3D21%26sd%3D360734450203&_trksid=p2056116.c100408.m2460