Older 61 to 266 build

[Ronie]

Since my 630 bit the dust, you can see it in the video thread, I'm going to take an old two piece coil 61 and put a 272 top end on it. All I've done so far is drill holes and install threaded inserts for an aftermarket 272 cover. After I tear the saw down and clean it up I'll put a little JBweld under the rear insert because the metal is thin there and half the insert it sticking through the other side.

 

[Ronie]

I got distracted with my 670 but I'm back on this one. I ended up putting the 272 cylinder on the 670 so I'm going to put a 266 cylinder on this one. Got the crankcase cleaned up this afternoon and hope to start on the cylinder tomorrow afternoon.

 

[Ronie]

I was surprised at how small the ports are on the 266 cylinder compared to a 670 or 272. The intake is tiny. The first pic is of the 266 and the second one is of a 670 cylinder that's going a another saw.

 

[Wood Doctor]

Ronie, I fear that nobody has ever advised me to upgrade my classic 61, anniversary edition to a 272 or any other Husqvarna model. So, I was unaware that it could even be done. I guess that I must admit that I will be interested in whatever happens here.

 

[Ronie]

Ronie, I fear that nobody has ever advised me to upgrade my classic 61, anniversary edition to a 272 or any other Husqvarna model. So, I was unaware that it could even be done. I guess that I must admit that I will be interested in whatever happens here.

It should be a fairly easy swap. I think the only thing that would mess it up is my unskilled attempt at porting.

 

[drf256]

The intake setup is totally different between a 266 and 272. The 266 has an intake block that bolts to the cylinder on its own, then the carb bolts to it. The 272 uses a more traditional modern setup where it all bolts to the jug as one unit with through bolts.

Also, bigger isn’t always better in porting. Take a good look at your intake tract and carb bore before you hog out your intake port. The only thing a huge intake port will do in a work saw is slow down throttle response and wear out the intake side of your piston.

 

[Ronie]

The intake setup is totally different between a 266 and 272. The 266 has an intake block that bolts to the cylinder on its own, then the carb bolts to it. The 272 uses a more traditional modern setup where it all bolts to the jug as one unit with through bolts.

Also, bigger isn’t always better in porting. Take a good look at your intake tract and carb bore before you hog out your intake port. The only thing a huge intake port will do in a work saw is slow down throttle response and wear out the intake side of your piston.

Thanks for your input. I plan on being very conservative on the porting and just opening the intake and exhaust a little bit. I might change the timing a little too. I think I've learned my lesson on hogging out the ports, it doesn't always make for a better running saw.

 

[drf256]

Which 272 jug do you have?

I’ve done a few, and I’ve found that the decomp Mahle had better numbers. At least for me, taking 20-30 out of the band and cutting the base for a squish of 20 left me with stock transfers right where I wanted them.

It was Jake Wells build and I hear that saw runs really well.

 

[Ronie]

It's a Mahle, I didn't get the stock numbers but after a base cut and very little grinding I ended with ex 102, tr 122 and in 78. It didn't take much to get them numbers and I think that it runs really good. The video is of it from last week.

 

[drf256]

Bravo buddy. That is a runner for sure. Not sure what else one would want from 72cc.

Well done.

 

[XP_Slinger]

Great running saw. Love me some 2-series

 

[Magic_Man]

It's a Mahle, I didn't get the stock numbers but after a base cut and very little grinding I ended with ex 102, tr 122 and in 78. It didn't take much to get them numbers and I think that it runs really good. The video is of it from last week.

Sounds pretty good and pulls hard, good work.

 

[Ronie]

I hope I can get this one to run close to the 670. It's going to have a short bar on it so it won't need as much torque.

 

[XP_Slinger]

I hope I can get this one to run close to the 670. It's going to have a short bar on it so it won't need as much torque.

Torque is fun with short bars too

 

[Intoxsawcated]

I hope I can get this one to run close to the 670. It's going to have a short bar on it so it won't need as much torque.

Better have a 14 inch bar on it then.

Sent from my SM-S767VL using Tapatalk

 

[Ronie]

Got started on the cylinder today and got a little of the roughing in done and then my flex shaft grinder burnt up. I checked the stock port timing without a base gasket and it was, ex 104, tr 126, in 71 and the squish was .0195. I'm leaving the squish where it's at and shooting for, ex 102, tr 102 and in 78. Some pics of what I've done so far.

 

[Ronie]

The Meteor piston is going to need a little clean up.

 

[XP_Slinger]

The Meteor piston is going to need a little clean up.

View attachment 210519 View attachment 210520 View attachment 210521

Wow...I’ve never seen a meteor with that much slag on it. Must have been Friday

 

[Ronie]

Wow...I’ve never seen a meteor with that much slag on it. Must have been Friday

It's the worst I've seen. That cylinder must have also been made on a Friday, look at the dip in the lower transfer. The other side is straight.

 

[XP_Slinger]

It's the worst I've seen. That cylinder must have also been made on a Friday, look at the dip in the lower transfer. The other side is straight.


View attachment 210544

I noticed that in your previous post. Other side isn’t like that??? Too bad it’s not on the intake side, be a good spot to grind a finger in there