poor mans big bore?

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russ61

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Looking at an 036 crankcase I've got sitting here nad an 038 mag jug and piston,the bolt hloes on the cly are'nt that far off from working.The catch seems to be the wrist pin size.I don't have a pin for the 036 yet but i'm wondering if I can make some press in sleeves out of 01 tool steel ,harden them and use the smaller pin?Might be cool a 72cc saw the size of an 036.:)Any thought as if this would work or has any body tried something similar?
Just thinking....
Russ
 
+1

:agree2: Brass will be a walk in short grass....easy. As long as the stroke is the same/close you should be ok as long as your squish is good and the piston does not travel too far down the cylinder.....exaust port has to open all the way too.
 
Yeah stroke is the same.You may be right ,bearing bronze might be the way to go.
Russ
 
I'd be interested to see this also. I know it's going to be a lot of work- an adapter will have to be made for a muffler since the exhaust port for the 038 cylinder will end up facing downward when mounted on the 036 chassis. The 036 case opening will have to be enlarged to allow a 52mm piston. The sides of the 038 cylinder will have to be machined to clear both the case and flywheel on the narrow 036 case. The top of the 038 cylinder have to be machined and the 036 top cover will have to be heavily modified so it can be fitted.

I toyed with this idea years ago but decided it was way more work than I wanted to do.
 
Ok Jacob you made me go look harder at this.5min. with the die grinder and I've got the cyl setting on the 036 case.Trim a fin a lifftle and put a small chamfer on the cly in 2 places and it fits.Piston does hit at BDC,I'll have to wait till I get a wrist pin it it to see if possibly I can shorten the skirt a little.Your right about the muffler though.I'll have to scrounge up an 036 muffler then I bet it will work.It's going to take a while to piece all of this together ,may be worth the wait!What kind of carb do you think ?The 038 had a Bing . 044 maybe or 066?Just guessing.
Russ
 
One more thing to check before going into this project. Measure the distance from thre crankshaft centerline to the top of the deck on both saws. If not the same, the same stroke will not matter, because it could be in a different place (height wise).
 
I'd be interested to see this also. I know it's going to be a lot of work- an adapter will have to be made for a muffler since the exhaust port for the 038 cylinder will end up facing downward when mounted on the 036 chassis. The 036 case opening will have to be enlarged to allow a 52mm piston. The sides of the 038 cylinder will have to be machined to clear both the case and flywheel on the narrow 036 case. The top of the 038 cylinder have to be machined and the 036 top cover will have to be heavily modified so it can be fitted.

I toyed with this idea years ago but decided it was way more work than I wanted to do.

A month ago I had the same idea but when I asked about trying it all the replies were not to try it. That kind of reply usually causes me to go ahead and do it. I had all the stuff here to do it but opted to build myself a hotrod 036 which I now thoroughly enjoy running the way its set up. If I had another 036 then I would step up and do this merging of parts. I have all the rest of the stuff so someone send me an 036. LOL
Pioneerguy600
 
I've got plenty 036 parts but nothing for 038, so I'm interested in this project mainly to know if maybe I can't limp these old horses down the road a bit longer. A drop-in kit, or at least the specs to build one, would be awesome.
 
Well went to the lathe and shortened the piston about .140.Clears the case no problem,plenty of room till it free ports.
Rupe,checked the deck heigth the best I can with calipers looks good,need to get to a height gage to be sure (at work).
About all I can do now,leaving town for a week on business:mad:I want to stay and play!
Russ
 
Well went to the lathe and shortened the piston about .140.Clears the case no problem,plenty of room till it free ports.
Rupe,checked the deck height the best I can with calipers looks good,need to get to a height gage to be sure (at work).
About all I can do now,leaving town for a week on business:mad:I want to stay and play!
Russ

when you get back from your trip i'd love to hear more about your progress on this mod. i am interested in what you find with your precise deck height measurements.
if the deck really is the same, i'd be very tempted to try a 036/038 hybrid. if it works out that the deck height is off just enough for a nice pop-up, that is even better! :chainsaw:

i can see fabbing up a muffler adapter to sandwich in between the cyl and muff. and i'm thinking (without looking at it) that a 028 muffler may work as a base for a custom muffler.

AS member 'southbound' uses a plastic called kaldex(?) which he molds with heat. i can see a custom 'hybrid' top cover in my future.
 
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when you get back from your trip i'd love to hear more about your progress on this mod. i am interested in what you find with your precise deck height measurements.
if the deck really is the same, i'd be very tempted to try a 036/038 hybrid. if it works out that the deck height is off just enough for a nice pop-up, that is even better! :chainsaw:

i can see fabbing up a muffler adapter to sandwich in between the cyl and muff. and i'm thinking (without looking at it) that a 028 muffler may work as a base for a custom muffler.

AS member 'southbound' uses a plastic called kaldex(?) which he molds with heat. i can see a custom 'hybrid' top cover in my future.

:agree2: You have to let us know the progress...... Can't leave us hanging now. :cheers:
 
You guys are missing the easy swap here.... I've been toying with this one for a while also just haven't gotten around to putting it all together yet, the muffler is the main fly in the ointment.... of course nothing a pipe wouldn't fix. :D

The 52mm mag jug would be the ticket if it weren’t for that whole pesky piston pin problem.

The 50mm super jug on the other hand is pretty much a straight swap and you'll find that the old 10mm 044 piston will drop right in as well... fab up a muffler, a little tickle here and there, and you're ready to go hunting with the big dogs. :clap:

One of you guys will probably beat me to getting it done though..... I've had all the parts for over a year now and just never have found the time to make it happen. :dizzy: I'd be interested in how it turns out though, a little sleeper 036 hybrid sure sounds like fun eh'. :D

:cheers:
 
i wish you guys would shut up erick is gonna figure out why my 036 pro will tear up his huskey. supper cabs and i told him it was just a better saw . its been fun but i will tell him sat at the gtg i am starting to feel guilty .:cry:
 
i wish you guys would shut up erick is gonna figure out why my 036 pro will tear up his huskey. supper cabs and i told him it was just a better saw . its been fun but i will tell him sat at the gtg i am starting to feel guilty .:cry:

Ummmm Huhhh? :dunno:

:laugh:
 
what about...

I've been thinking about doing this mod too. If I understand it correctly, a non-windowed piston will not work, correct? I've got a 52mm non-windowed piston with the 10mm wrist pin from an olympyk 284F. I've put an 064 piston in an efco saw before and it ran great...not that that says anything about the 038 mag cylinder timing, but the pistons appear to be compatible besides the window.
 
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