craftsman/roper (917.353770)

[jerrycmorrow]

finishing a rebuild and lipstick on a craftsman/roper 3.7. it has a walbro sdc-73 on it now; only has a low adjustment needle. wondering what carb, with a h and l needle would be a suitable replacement and if anyone has one. i was thinking about doing a MM on it but didn't cause i wouldn't be able to tune it without a different carb.
anyone?

 

[67L36Driver]

Look for an SDC off a Homie XL-12 or SXL. Throttle and choke shafts are easy to swap to match your controls.

Hard part will be elongating the hole in the carb. box. Homie grommet may work.

I think my Craftsman/Roper has a Tilly HS with H and L adjustments.

 

[Warped5]

Hey Jerry!

Post a pic or few of that SDC. I might have one here for ya.

 

[jerrycmorrow]

thanks guys. pix tomorrow

 

[jerrycmorrow]

also read somewhere that some of these saws come with a tilly HS79A that supposedly has an H screw. that would be nice as well.
here's some pix

more on the next

 

[jerrycmorrow]

two more.

preciate yalls help on this.
jerry

 

[Warped5]

Jerry, I have a couple of possible options for you here. Is it important that the adjustment screw(s) reach the side of the airbox?

 

[jerrycmorrow]

thanks ted
dont think so. have to look but seem to recall that theres a box inside the handle assembly that the filter sits on so not necessary to seal around the screws. also, may be able to use the existing screws (got a parts saw too). i'm thinking the throttle is gonna be the critical issue. let me look and get back to ya.
what ya got?
what ya need?

 

[Warped5]

thanks ted
dont think so. have to look but seem to recall that theres a box inside the handle assembly that the filter sits on so not necessary to seal around the screws. also, may be able to use the existing screws (got a parts saw too). i'm thinking the throttle is gonna be the critical issue. let me look and get back to ya.
what ya got?
what ya need?

Wowzers, you're asking for a lot on a Thursday ...

I'll post pics later and try to think of what I need ..

 

[Eccentric]

what is under that cover plate on the side of the carb with the throttle stop and low speed screw?

Accelerator pump diaphragm. Some SDC's had them. The carb on my Homelite XL-103 has it too. Other than that saw and my Roper, none of my SDC equipped saws have the accelerator pump. Because of that, I have a growing collection of SDC accelerator pump diaphragms from rebuild kits....

 

[67L36Driver]

Yup, accel. pump. I can see the hole that activates it in the face of the carb. gasket. Hole in throttle shaft lines up at WOT. Located at 2:00 o'clock.

Jerry: You could just set the metering lever high(ish) to fatten up the high speed mix.

 

[jerrycmorrow]

...Jerry: You could just set the metering lever high(ish) to fatten up the high speed mix.

may end up doing that. how much you think? just a fuzz?

 

[67L36Driver]

may end up doing that. how much you think? just a fuzz?

Try level first and then .020"-.025" above if it needs fatter. Use your spark plug gauge.

I have some XL-101 type SDCs but the fuel inlet spigot is bigger than what I see on yours.

Edit: I have one SDC-12 left from my Homie binge.

 

[workshop]

Hey Guys, I just finished up putting a XL12 SDC carburetor on one of my 3.7 Ropers/Craftsmen saws. Because the idle screw is in the way of the high speed adjustment screw, I wound up cutting the high speed screw down about a half inch so it would fit under the throttle arm and cut a groove so a screwdriver would fit it. You might consider drilling a whole in the throttle arm to adjust it while running. I just turn the saw off, open the trigger and make an adjustment, then start it up again and see how it does. Also I did transfer the choke shaft and throttle shaft from the original carb over to the Homelite carb. Slid right in. As a trial run I pulled the guts out of the muffler, But left the sheet metal covering the final exit of the muffler. VERY snappy response from idle to full throttle. I need to get a chain and try it in some wood. Hopefully will have enough snort to pull a 24 inch bar with 325 chain. Also removed the fuel inlet fitting from the original carb and pressed it into the Homelite carb so the fuel line would fit easier.

 

[machinisttx]

Hey Guys, I just finished up putting a XL12 SDC carburetor on one of my 3.7 Ropers/Craftsmen saws. Because the idle screw is in the way of the high speed adjustment screw, I wound up cutting the high speed screw down about a half inch so it would fit under the throttle arm and cut a groove so a screwdriver would fit it. You might consider drilling a whole in the throttle arm to adjust it while running. I just turn the saw off, open the trigger and make an adjustment, then start it up again and see how it does. Also I did transfer the choke shaft and throttle shaft from the original carb over to the Homelite carb. Slid right in. As a trial run I pulled the guts out of the muffler, But left the sheet metal covering the final exit of the muffler. VERY snappy response from idle to full throttle. I need to get a chain and try it in some wood. Hopefully will have enough snort to pull a 24 inch bar with 325 chain. Also removed the fuel inlet fitting from the original carb and pressed it into the Homelite carb so the fuel line would fit easier.

Any chance of a video? :msp_w00t:

 

[workshop]

Any chance of a video? :msp_w00t:

It'll be a few days, but I will try. I don't have much luck getting pictures to load up, so I don't know, but will try. By the way, it's one of the saws you sent me.:msp_wink:

 

[machinisttx]

I figured so. I'm guessing it was the one without the handguard?

 

[workshop]

Hey Guys, I just finished up putting a XL12 SDC carburetor on one of my 3.7 Ropers/Craftsmen saws. Because the idle screw is in the way of the high speed adjustment screw, I wound up cutting the high speed screw down about a half inch so it would fit under the throttle arm and cut a groove so a screwdriver would fit it. You might consider drilling a whole in the throttle arm to adjust it while running. I just turn the saw off, open the trigger and make an adjustment, then start it up again and see how it does. Also I did transfer the choke shaft and throttle shaft from the original carb over to the Homelite carb. Slid right in. As a trial run I pulled the guts out of the muffler, But left the sheet metal covering the final exit of the muffler. VERY snappy response from idle to full throttle. I need to get a chain and try it in some wood. Hopefully will have enough snort to pull a 24 inch bar with 325 chain. Also removed the fuel inlet fitting from the original carb and pressed it into the Homelite carb so the fuel line would fit easier.

Ok, I screwed up here. Clearly wasn't paying attention to what I have. The carb that was original to the saw was a Tillotson. The replacement carb is also a Tillotson, HS19A, according to my bifocals.
I will try to upload some pictures of the completed carb, bear with me please.
View attachment 309284

 

[workshop]

Sorry about the fuzzy pictures, best I could do. You can see how much shorter I had to make the high speed screw to fit in behind the throttle arm. And see that the arm covers it up. Thought of trimming the arm but it is required because the idle screw is part of the saw, not the carburetor. I apologize for jumping the gun in my previous post. I have given myself 10 demerits for the infraction.
My son thinks he can upload videos from his phone to our computor but will have to wait until Saturday or Sunday to do it.

 

[workshop]

[video=youtube_share;TEpNRYA3VN8]http://youtu.be/TEpNRYA3VN8[/video]

This is the modified saw. Tillotson carb with H/L adjustments and muffler modification.