Finally Ported my craftsman 3.7......vid attatched!

[lumberjackchef]

Well with all of the threads around here lately on porting, I broke out the dremel last night and went ahead and took it all the way. I started off with the degree wheel but I need to make a better set up cause there is definitely a learning curve to getting accurate and repeatable numbers.

​

I ended up just looking at improving the flow the best I could without compromising compression. I ended up with this:

removed base gasket
widened exhaust
widened intake
pointed the transfers back a bit more (top only)
and punched a couple of 3/8 holes in the front of the muffler
(not beautiful but effective)

Here it is in action.

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The Wood is Pine and the 028 is only for a reference as to the density of this wood. It was not a race! Both chains were fresh off of the grinder.

It picked up a lot or rpms in the wood. If it would've been earlier when I started this project I would've been able to get a before video but I can definitely feel it! I'm hooked. And I thought Cad was bad!:hmm3grin2orange:

 

[PLMCRZY]

Thing runs goood!!!!!

 

[slipknot]

Who makes this saw for sears? solo? thats a nicer runner you got there!
Sure seemed to come to life.

You know what I think of the new smileys??? this...oop:

 

[bowtechmadman]

Looks and sounds great. I'm gonna guess Poulan 3700 rather than a Solo.

 

[o8f150]

all i can say is wow

 

[lumberjackchef]

Who makes this saw for sears? solo? thats a nicer runner you got there!
Sure seemed to come to life.

You know what I think of the new smileys??? this...oop:

Its the same as the Poulan 3700 countervibe. But it really brought it to life. I can lean hard on it now, and she just keeps digging

 

[blsnelling]

You did a very nice job there! Congrats

 

[PLMCRZY]

Its the same as the Poulan 3700 countervibe. But it really brought it to life. I can lean hard on it now, and she just keeps digging

I was impressed with mine stock, except the weight. Dang, they get heavy!

 

[lumberjackchef]

Just wanted to say thanks for all of those members who have taken the time to show us all the ins and outs of porting, it is much appreciated! I know that i have a lot to learn but man it sure seems like its gonna be a fun ride.

 

[JT78]

Congradulations looks like you done good. I have run a few of these is stock form and I will say they were a bit disappointing for a 60 cc class saw. Looks like they wake up and respond pretty well to a little port work. Watch out it is addictive you will be porting everything you own before you know it.

 

[Modifiedmark]

I was impressed with mine stock, except the weight. Dang, they get heavy!

Dang Clay, are you really from Texas? I'll bet your embarssing the rest of Texas they way you keep whinning about the weight of them. I ought to send you a Pro Mac 610 and make you run one on them for awhile. That would make you man up or kill ya one or the other.

Good thing your going to get a nice little girly man 026 soon. :loser:

(I'm messing with ya kid)

I have run a few of these is stock form and I will say they were a bit disappointing for a 60 cc class saw.

Compared to what? A a ported 359? They really compare quite well with other 60cc saws of its era.


They really are quite restricted stock in the mufflers though. A simple muffler mod really wakes them up.


To the OP, I got a 3.7 like that that I rebuilt and did a little porting on. I'm not a porter by any means so I kept it really conservitive and it still seems to run prettty good as well.

Thanks for posting the video, yours looks like it really runs well. Also it reminded me of why I only kept my 028 for about 24 hrs. LOL

 

[FATGUY]

nice work!

 

[JT78]

Hey Mark actually I was thinking more so comparative to most stock 60cc class saws of today. I mean no disrespect I really enjoy the older saws also but they even felt a little sluggish compared to my stihl 041 and homelite xl12 the 041 is 61cc and the xl12 I think was 57cc. I'm not downing the 3.7 just saying they seemed a little weak stock I was amazed at how this one ran after he ported it.

 

[PLMCRZY]

Dang Clay, are you really from Texas? I'll bet your embarssing the rest of Texas they way you keep whinning about the weight of them. I ought to send you a Pro Mac 610 and make you run one on them for awhile. That would make you man up or kill ya one or the other.

Good thing your going to get a nice little girly man 026 soon. :loser:

(I'm messing with ya kid)






Compared to what? A a ported 359? They really compare quite well with other 60cc saws of its era.


They really are quite restricted stock in the mufflers though. A simple muffler mod really wakes them up.


To the OP, I got a 3.7 like that that I rebuilt and did a little porting on. I'm not a porter by any means so I kept it really conservitive and it still seems to run prettty good as well.

Thanks for posting the video, yours looks like it really runs well. Also it reminded me of why I only kept my 028 for about 24 hrs. LOL

When i go cut, its a hobby of mine i dont want to lug around 18 pounds and make it a job. Its amazing how light these little stihls are, i fell in love with one after i picked up a 260pro in a dealer.

 

[Modifiedmark]

Hey Mark actually I was thinking more so comparative to most stock 60cc class saws of today. I mean no disrespect I really enjoy the older saws also but they even felt a little sluggish compared to my stihl 041 and homelite xl12 the 041 is 61cc and the xl12 I think was 57cc. I'm not downing the 3.7 just saying they seemed a little weak stock I was amazed at how this one ran after he ported it.

The 041 is a good one, but I have run most all of that size from that era, and the 3700 is right up there with the best of em.

Some of the red Craftsman 3.7 were not actually 3700's. Some were really 3800's and those had the unplated cyls and thick rings. They seem a little sluggish compared to the 3700's if you ask me.

Like I said also, they really need the mufflers opended up a little to make em shine.

I got a stock 3700 here with just a muffler mod that hangs close to my 262XP in most firewood.

No problems here with me, just wondering what you compared them to, but we can see that the original posters saw is no slouch!

 

[bluesportster02]

Good job sounds and looks great

 

[Arrowhead]

Good job. I bet within the next week or so, all your saws will be ported.

 

[lumberjackchef]

Ok so I went a step further with the process. The squish on this saw was really high stock and I had already taken out the base gasket. But it still setting at 25 without the gasket. So I decked the cylinder to obtain .017-018, ran the numbers and they were as follows:

Exhaust opens @ 100* dur/160*
Transfers open @ 125* dur/110*
Intake opens @ 72* dur/144*

I decide to drop the intake just a little, so now its at 73*/ dur/146*


I put it back together and tried it out, but it acted like it was having a vacuum leak at higher rpms so I shut it down and tore into once again, thought it might have something to do with the tight squish and not raising the transfer/exhaust. So I made a gasket from an aluminum can, that yielded me a good .020-.021 squish. I replaced the time hardened fuel line as well (only one year old and hard as a rock) and just got i fired back up again. It seemed to be running good but I was only able to run it for a few seconds because it was late. So I'll have to wait till in the morning to see if my symptoms have disappeared completely.

Questions: How do these timing numbers look for a work saw?

As I am looking for a saw that can rip as well as crosscut while i'm carving in semi-hard woods, I need more torque, Is there anything in particular that you guys would recommend to unleash a little more power from this saw?

 

[a. palmer jr.]

The 041 is a good one, but I have run most all of that size from that era, and the 3700 is right up there with the best of em.

Some of the red Craftsman 3.7 were not actually 3700's. Some were really 3800's and those had the unplated cyls and thick rings. They seem a little sluggish compared to the 3700's if you ask me.

Like I said also, they really need the mufflers opended up a little to make em shine.

I got a stock 3700 here with just a muffler mod that hangs close to my 262XP in most firewood.

No problems here with me, just wondering what you compared them to, but we can see that the original posters saw is no slouch!

Mark, do you have any pics of a modded 3.7 muffler? I might try opening up my 3.7 and see how it does. The only problem I have here is that the neighbors are pretty close and if it makes it a bunch louder it might be a problem.

 

[tombukt2]

hey there me likes the 2700-3300 hartil designed craftsman (Red-grey) or black (pro) these are 11 pound units and can be taken in the 70 some odd CC's range . Seriously light powerful and in its day, assembled or made in USA.. usually can be had for free, this unit 180 bux of parts and an afternoon will get it up n running. pretty serious stuff in the 80's and still today . seriously this setup ran circles around most saws then and today and was light .. no transfer work etc build and cut .. me thinks still today this unit built like so still is a kick azz deal under 200 bucks for 70 cc and from LA. USA