Stihl Carburetor - Walbro HDC 17 rebuild seat assembly

[RichardS1630]

I am attempting to rebuild a carburetor for a Stihl 015L. The carb is a Walbro HDC 17.

A little backstory: I had this saw serviced by a small engine repair shop in Roswell, GA. I didn't have time to do it myself and trusted them to do a better job than I could. I was wrong. The saw only ran for about 2 or 3 small jobs (less than 15 min each). After the saw stopped working again, I took it upon myself to check it out. As of now, I have replaced the sparkplug wire which was disintegrating and torn apart the carb. From what I can tell, the shop replaced the primary diaphragms (17, 20 & 15) and metering diaphragm (22) when they serviced the fuel system, but neglected the entire assembly on top of the check valve (19). That's where the real grit/grime was, and the small screen and diaphragm over the seat assembly (12) was toast. All numbers reference the typical parts diagram for these carburetors, which I've attached as a file.

So I ordered another diaphragm kit and a seat assembly. The diaphragm kit is straight forward, but the seat assembly is giving me headaches. The retaining ring and screen came right out, but the brass ring appears to be either adhered (fossilized?) or punch-set into the body of the diaphragm. I have a new assembly to put in place, but cannot get the old one out. I've tried using dental tools, scribes, etc, but for fear of causing more damage, I'm at a stand-still. Any advice out there? Has anyone else done this before? Thanks in advance...

 

[pioneerguy600]

Ok, I might not quite understand what you are attempting to do with this carb. The needle seat does not come out of this carb. and is not replaceable. The fuel screen is replaceable, remove the retaining ring and screen, clean and replace with new parts. Can you explain which brass part you are trying to remove.?

 

[pioneerguy600]

I am attempting to rebuild a carburetor for a Stihl 015L. The carb is a Walbro HDC 17.

A little backstory: I had this saw serviced by a small engine repair shop in Roswell, GA. I didn't have time to do it myself and trusted them to do a better job than I could. I was wrong. The saw only ran for about 2 or 3 small jobs (less than 15 min each). After the saw stopped working again, I took it upon myself to check it out. As of now, I have replaced the sparkplug wire which was disintegrating and torn apart the carb. From what I can tell, the shop replaced the primary diaphragms (17, 20 & 15) and metering diaphragm (22) when they serviced the fuel system, but neglected the entire assembly on top of the check valve (19). That's where the real grit/grime was, and the small screen and diaphragm over the seat assembly (12) was toast. All numbers reference the typical parts diagram for these carburetors, which I've attached as a file.

So I ordered another diaphragm kit and a seat assembly. The diaphragm kit is straight forward, but the seat assembly is giving me headaches. The retaining ring and screen came right out, but the brass ring appears to be either adhered (fossilized?) or punch-set into the body of the diaphragm. I have a new assembly to put in place, but cannot get the old one out. I've tried using dental tools, scribes, etc, but for fear of causing more damage, I'm at a stand-still. Any advice out there? Has anyone else done this before? Thanks in advance...

opcorn:

 

[RichardS1630]

When I ordered the replacement parts, the screen and retaining ring came in a new brass seat. See attached photo. Seems logical that the original seat can be removed and replaced to allow for direct access to the diaphragm.

I'm not trying to make this more complicated than it needs to be, but if I can order the part, it seems like it should be replaceable...

 

[rich450es]

i have found that some kits come with more parts then are needed to fit different models ......

 

[pioneerguy600]

That brass cup would be pressed in, won`t be easy to get it out.

 

[RichardS1630]

Thanks for the help and insight, everyone.

 

[ncfarmboy]

The Walbro carb repair tool kit has the puller and install tools. Can't remember PN for kit around $50.00.
Shep

 

[cruxmon]

The tool kit referenced above is Walbro PN 500-500. It contains a small slide hammer that hooks underneath the brass seat to pop it out. Generally takes a few blows working circumferentially around the brass seat to get the job done. A poor man's alternative is to put a nice sharp drill bit with a diameter slightly smaller than the brass seat into your trusty drill and drill it out. Generally what happens is the moment the bit engages the brass seat, the brass seat spins free, a wal-la. Easier with the drill bit than the small slide hammer but with greater risk of a permanent boo-boo.

 

[rmh3481]

Maybe this will help, HDC service manual. Look over the disassembly instructions with the lean and rich sections and see if they make sense. If you need parts, parts tree or walbro can set you up with one of their distributors.

 

[rmh3481]

If you donr want to do the work yourself, look up chainsawr they offer a $50 rebuild service.

It reads: We do chainsaw carburetor work.

$40 Basic Package Includes: cleaning, inspection, gasket and diaphram kit, return postage.

$50 Deluxe Package Includes: cleaning, inspection, gasket and diaphram kit, replacment of all broken or worn out ‘hard’ carburetor parts, return postage.

https://store.chainsawr.com/blogs/news/1184152-carburetor-rebuilding-service

 

[HarleyT]

2 1/2 year old thread....