Re-building a 272 with a Titanikel 52mm top end

[meglodon]

I'm in the process of collecting parts and rebuilding a 272 short block I acquired. It was pretty dirty (as I guess most of these are)


I have started to gather some parts for it. Titanikel top end, mix of oem and chinese parts so far. (sort of a budget build but one to get some experience building)

and dug into tearing things apart.



Intially I thought things looked decent on the short block (although it was quite dirty) but splitting the cases, I found that the bar stud threads were messed up


(and the front one has one spun a bit causing some damage in the case half. I debated about looking for a new case half I've found a couple on ebay but they weren't in much better shape to make me jump on them. (and apparently I can't post in the want to buy section here yet)

Overall, things have been cleaning up fairly decent and I have 2 new oem bar studs on order. At this point I am planning to re-enforce the portion of the case that split with some jb-weld (but open to suggestions) before putting things back together.



It'll have new bearings and seals, crank seems to be in decent shape.

I was going to do some port work on the cylinder, but having read a bit about the Titanikel plating being super hard and chipping if you're not careful I may hold off. I wish I had read about that before I had ordered it so while I have diamond stones for my foredom I may just check the numbers and run it.

We'll see what they come in at.

More to come as I get the parts I need to put this back together.

 

[meglodon]

the crank was pretty dirty, but seems to be cleaning up decent.

 

[meglodon]

new bolts showed up yesterday, As you can see the case has some chain rash but no holes. I was able to get the bolts in without any problem. They slid in a bit looser than I would have liked so added some threebond 1184 to seal them and reinforced around the front bolt webbing with steel reinforced JBweld.

I've got a bearing, seal and gasket set from The Duke & I'm planning to put the bottom end together shortly.

 

[meglodon]

got the oil pump cleaned up, bottom end together, and seals installed.



Used a heat gun and watched the temps. (first time I've tried it this way) I think it worked well for the bearings on the crank and crank into the pto crank half but the flywheel case half fought a bit. May not have gotten it hot enough to hold the temp while I got them together. In the end, Had to get a little creative but got it together.





Crank spins very freely and it's starting to look more like a saw!

 

[meglodon]

Oh, before I put the cases together I thought about looking at doing some case flowing.


It looks like there might be some room to play here, but because the cylinder is the Titanikel I'm not sure if I want to try porting it. I figured this would be fine the way it is and hopefully the timing numbers aren't terrible with no base gasket.

The case halves were put together with the threebond 1184 on both sides of the gasket.

 

[IntegrityCarpentry]

Looks good!!!

 

[meglodon]

Looks good!!!

Thanks!

Over my lunch break I took a few minutes and cleaned the flywheel up and got it on the crank. The flywheel nut was pretty rounded out by someone before me, for rough assembly it will work but I'll have to source another before I turn the saw loose.

The fuel tank:
replaced the fuel line & fuel filter, rubber throttle boot and the anti-vibe isolation mounts.

Got the two pulled together and starting to look a bit like a saw again!

 

[meglodon]

One of the things I'm either missing or is still in my pile of parts for this is the chain catcher. (could be the reason the saw's clutch case side is all chewed up)

 

[meglodon]

Got an OEM wrist pin bearing for it.


Checked the squish without a base gasket: .020





I am still learning how to use the digital timing wheel (which is pretty sweet) and I am not planning on porting due to my concern around comprimising the plating, heres what it is stock Rough Numbers (from what I read)
- exhaust is opening at 103.3 atdc
- transfers open at 123.3 atdc
- intake opnes at 74.0 degrees

So, from a future porting stand point, if I were to grind it, I might try to drop(raise?) 3 degrees to 100 / 120

Other than that, I cleaned up the piston and removed what flash there was, sharp corner stress points, and chamfered the edges. It's in the oven heat treating at 450 for 4 hrs, then into an ice bath.

Overall, it's coming along and should be put together tomorrow afternoon. I have a few more parts to clean (the starter cover and all things attached are filthy) Hopefully I will be able to get that done and get it ready to do a leakdown/pressure test. Then heat cycle a few times this weekend (assuming I get things cleaned and source all the various bolts which might be needed.)

 

[IntegrityCarpentry]

I can try to send a pic of my metal one. It’s not the best. I have thought about ordering a different one sometime.

This is the one I want to order. The included one on mine was just an aluminum L with a hole in one leg. Basically like this with no rounded parts.

https://www.ebay.com/itm/2331456799...SuwDo-WSEq&var=&widget_ver=artemis&media=COPY

 

[IntegrityCarpentry]

Looks like you have all new buffers. Good job. Did you put new springs in trigger and handle? I got a small kit of parts and the gas tank lid leaked. I just put the old one back on.

 

[IntegrityCarpentry]

This is what my chain catcher looks like, except squared off and not angled.

 

[meglodon]

I can try to send a pic of my metal one. It’s not the best. I have thought about ordering a different one sometime.

This is the one I want to order. The included one on mine was just an aluminum L with a hole in one leg. Basically like this with no rounded parts.

https://www.ebay.com/itm/2331456799...SuwDo-WSEq&var=&widget_ver=artemis&media=COPY

Thanks, that looks pretty good! I want to say I have a spare in the pile of stuff I have but I'll have to do some digging. If I don't find it I'll order that one. Thanks for sharing the link!

Looks like you have all new buffers. Good job. Did you put new springs in trigger and handle? I got a small kit of parts and the gas tank lid leaked. I just put the old one back on.

I didn't put new springs in the trigger. I do have some aftermarket ones but these seem pretty decent, so I was planning to run them for now.

I did dig through enough parts and found the bolts I needed to get the cylinder assembly together (muffler, cylnider & carb) so it's ready to go on tomorrow.

 

[IntegrityCarpentry]

Thanks, that looks pretty good! I want to say I have a spare in the pile of stuff I have but I'll have to do some digging. If I don't find it I'll order that one. Thanks for sharing the link!

I didn't put new springs in the trigger. I do have some aftermarket ones but these seem pretty decent, so I was planning to run them for now.

I did dig through enough parts and found the bolts I needed to get the cylinder assembly together (muffler, cylnider & carb) so it's ready to go on tomorrow.

That’s awesome. Your getting closer.

 

[meglodon]

Yup, just pulled the piston from the heat treat, seems to be good. but gotta head to bed (that alarm goes off early.)

 

[The Shooters Apprentice]

When I did the cases on my Jonsered 625/670 build I couldn’t get the crank to seat into the case for the life of me with heat. Got it as hot as I dared and pulled it together with the case bolts, then centered the crank with a dead blow hammer.

 

[meglodon]

I can try to send a pic of my metal one. It’s not the best. I have thought about ordering a different one sometime.

This is the one I want to order. The included one on mine was just an aluminum L with a hole in one leg. Basically like this with no rounded parts.

https://www.ebay.com/itm/2331456799...SuwDo-WSEq&var=&widget_ver=artemis&media=COPY

Thanks, that looks pretty good! I want to say I have a spare in the pile of stuff I have but I'll have to do some digging. If I don't find it I'll order that one. Thanks for sharing the link!

Looks like you have all new buffers. Good job. Did you put new springs in trigger and handle? I got a small kit of parts and the gas tank lid leaked. I just put the old one back on.

I didn't put new springs in the trigger. I do have some aftermarket ones but these seem pretty decent, so I was planning to run them for now.

I did dig through enough parts and found the bolts I needed to get the cylinder assembly together (muffler, cylnider & carb) so it's ready to go on tomorrow.

 

[meglodon]

So, got the piston on and cylinder in place ... I made sure that the wrist pin circlips were seated in the grooves (rotated around 360 and oriented so vertically)

1184'd the base and cylinder stuck it together and then I realized I forgot the boot between the carb and the cylinder. . .

 

[meglodon]

So of course, because I just had cinched everything down and sealed everything, I have elected to do things the hard way to get this on. I put some 1184 between the plastic block and the gasket to keep it in place and I'm using the carb/bolts to make sure it's in the right spot and sets/sticks (hopefully) the 1184 is some pretty impressive stuff (from what I've seen so far) so I don’t' have any particular worries about that.

 

[IntegrityCarpentry]

Sounds like one of my lessons. Hope that carb is good. Some people have great experiences with generic. I have had two and both gave me fits. I have oem tillotson one on mine now. For me I couldn’t get adjusted, and the idle speed screw was loose and kept loosening while the saw ran. What do you use to hold the rings snug while installing cylinder? I have never had a saw that far apart.