Porting the 046-D Jug

[MustangMike]

I visited Al down on Long Island today, and he taught me about porting a saw by demonstrating on my 046-D Jug.

Thank you very much Al, you do great work! Also thanks to Randy for sharing some #s, and to Keith for encouraging me to take advantage of this opportunity.

It was a real learning experience, and now I got a fabulous jug to put on that 460!

Should be picking up the parts on Monday, and hopefully will have it running soon after.

Still not sure why the saw was in the parts heap in the first place, there was nothing wrong with the P&C, as I had been lead to believe there was. There may be other problems I've yet to ID.

 

[MustangMike]

Some more pics:

 

[MustangMike]

We cut the base, we cut the squish (ended up right at 20), we fixed the port timing and opened em up a bit, and added bridges.

And, if I ever need it, I have a left over 460 jug that is in great shape, and has some pretty nice ports right from the factory (Al said it almost looked like it had been ported), other than they did not clean up the casting marks from the ports.

Can't wait to get this beast running, a put it into some wood.

 

[Ironworker]

That's pretty cool, who's Al.

 

[MustangMike]

drf255

 

[Stihlbro]

Sounds like a fun time.

 

[MustangMike]

A good time, and a real learning experience, but I won't pretend that I understand bridge ports.

Also, anyone know why the 046 D jug has that little triangular hole to now where on the bottom??? The 460 does not have anything similar.

 

[Backtroller]

That's pretty cool, who's Al.

Al's a very generous guy who totally helped me out with my saw. Answered all of my goofy questions and taught me things along the way. There are some really good people on this forum and he's at the top of my list.

 

[jmssaws]

I talk to him on the phone almost every day, he's a hell of a guy with a knack for porting. I bet that saw is a runner cause I cn the numbers. Lol

 

[Mastermind]

An amazing group of people we have gathered together.

 

[Backtroller]

Final numbers dead on at 103/120/82.

Yes, Good numbers (036 cylinder )

 

[MustangMike]

I think Al takes better pics than I do also:

 

[MustangMike]

More of Al's pics:

 

[cgraham1]

An amazing group of people we have gathered together.

... and me, Randy!

 

[Keith Gandy]

I visited Al down on Long Island today, and he taught me about porting a saw by demonstrating on my 046-D Jug.

Thank you very much Al, you do great work! Also thanks to Randy for sharing some #s, and to Keith for encouraging me to take advantage of this opportunity.

It was a real learning experience, and now I got a fabulous jug to put on that 460!

Should be picking up the parts on Monday, and hopefully will have it running soon after.

Still not sure why the saw was in the parts heap in the first place, there was nothing wrong with the P&C, as I had been lead to believe there was. There may be other problems I've yet to ID.

Sounds like you guys had a fantastic day!! Pretty cool that Al is a standup fellow willing to share and help a fellow member out! Thats what this site is and hopefully will continue to be and not turn into any pissing matches. Mustang I bet u have 1000 more questions now and excited to see the porting process? Its addictive!!

 

[mdavlee]

Was this cylinder one with short blowdown to begin with?

 

[drf256]

Was this cylinder one with short blowdown to begin with?

We never timed it before the Mods. We also didn't time the 460 jug.

It probably did have short blowdown. I didn't have to raise the transfers or exhaust that much after the machine work.

A few things were quite surprising on this build.

The later non-D 460 jug had much larger factory ports. The intake was nearly perfect and nice and rectangular. Mustang Mike, can you post some pics of that cylinder? Other than changing the timing and playing with the band for compression, I actually don't think I would do a thing to the jug except for sanding the ports a bit. They were just that good. I woulda never thought that. Mike wanted the D jug, so we went with it.

The D jug had a much thicker base than the 046 jug. After taking .042 off the base plate, it was still thicker than the 460 jug.

Squish was really loose on the factory 046 jug. We got .032 without a gasket. So we cut the base .042 and pulled
.030 out of the band for a final squish of .020 with .023 solder.

I happened to have a new Meteor here and Mike hadn't gotten his OEM piston yet. Thankfully we double checked the used OEM piston against the meteor before we used the meteor to make our skirt lines. The meteor's skirts were much wider. IIRC, maybe more than .060.

I'm wondering now if Stihl made the later jugs with bigger ports and that's why the meteor is wider. Would work with both jugs.

This is the first 046 I've ever done. Anyone else have similar experiences with the jug geometry?

 

[mdavlee]

I don't remember much difference. If you didn't raise them a lot compared to the exhaust it was a short blowdown jug. They were around 14 degrees. I've noticed some differences in the squish. Some will be .017" without a gasket and some .025". I have a meteor in mine now. I have one OEM piston I can measure if I tear mine down to look at the crown.

 

[drf256]

The was a really big difference in the size of all the ports. It was readily apparent. The 460 uppers, exhaust and intake were all larger. The finish of the ports was nicer on the 046 jug. Much more casting flash on the 460 jug.

I raised the transfers probably .200 and the exhaust maybe .100 after the cuts.

 

[Keith Gandy]

We never timed it before the Mods. We also didn't time the 460 jug.

It probably did have short blowdown. I didn't have to raise the transfers or exhaust that much after the machine work.

A few things were quite surprising on this build.

The later non-D 460 jug had much larger factory ports. The intake was nearly perfect and nice and rectangular. Mustang Mike, can you post some pics of that cylinder? Other than changing the timing and playing with the band for compression, I actually don't think I would do a thing to the jug except for sanding the ports a bit. They were just that good. I woulda never thought that. Mike wanted the D jug, so we went with it.

The D jug had a much thicker base than the 046 jug. After taking .042 off the base plate, it was still thicker than the 460 jug.

Squish was really loose on the factory 046 jug. We got .032 without a gasket. So we cut the base .042 and pulled
.030 out of the band for a final squish of .020 with .023 solder.

I happened to have a new Meteor here and Mike hadn't gotten his OEM piston yet. Thankfully we double checked the used OEM piston against the meteor before we used the meteor to make our skirt lines. The meteor's skirts were much wider. IIRC, maybe more than .060.

I'm wondering now if Stihl made the later jugs with bigger ports and that's why the meteor is wider. Would work with both jugs.

This is the first 046 I've ever done. Anyone else have similar experiences with the jug geometry?

Yes. My buddy John has a 1st yr 046d that he barely touched. Very impressive