OT: Welch plug for briggs carb.

[pjf134]

I have a question of what would be the best way to make a welch plug for a 10 hp briggs carb. The plug is just a flat plat that closes off the end of the carb. I have a bigger plug that I can use but thinking of a way to machine it down to right size is a pain. I think I will spend the $3 for a new one, since I have to order some other parts also, but just thinking of a way to machine it without waiting for the UPS guy in the future. Thickness is a problem also but can machine down if needed. Any great ideas out there?
Thanks,
Paul

 

[Tony Wells]

Part off a thin disk, then use a center punch on a soft backing material (lead, for instance), put a dimple in the center of it to reduce the OD. Then slip it into the hole, dimple side out, and use a flat punch to knock it back towards flat, expanding it tightly into the bore.

 

[pdentrem]

Stamp it out. Take two pieces of steel plate pin them together with dowels, and bore the size hole required in both. Backbore one of the pieces, the one that is going to be the bottom punch, to produce a short land, about .100" is all you need for the land. The backbore/counterbore has to be just a bit bigger, .010" would be good. Turn a punch that just fits. A sliding fit and harden the punch and the bottom pieces and temper back to straw. You do not want it fully hard as you are going to hit it with a hammer. Seperate the 2 plates by placing a washer on the dowels between the plates, that way you can insert the material to stamp. Hit with hammer on a solid surface, concrete floor or heavy steel bench. Have a piece of tempered hardboard to receive the blank that you just punched out under the die set.

Or buy the plug. This way is cheaper! ;D

 

[The Liberal Arts Garage]

Part off a thin disk, then use a center punch on a soft backing material (lead, for instance), put a dimple in the center of it to reduce the OD. Then slip it into the hole, dimple side out, and use a flat punch to knock it back towards flat, expanding it tightly into the bore.

Measure exact size, Order from engine rebuilders.Getcorrectdriver from your travelling Tool Guy. Flat punch doesn't do it. ....BLJHB

 

[Billh50]

welch plugs are normally domed. they get inserted with dome out in a hole the same size. Then when hit with a punch they expand sealing the outer edges.

I used to put them in blow molds for plastic bottles all the time when I was a mold maker. They are cheap and most auto parts stores have them in stock.

 

[visenfile]

I believe I read somewhere the rebuilders of little carbs sometimes use lead sinkers to make the plugs which are punched or staked?? Check me.

 

[JimDawson]

I believe I read somewhere the rebuilders of little carbs sometimes use lead sinkers to make the plugs which are punched or staked?? Check me.

For the small plugs in the cross drill holes that would work. The particular plug the the OP is talking about is about 3/4 inch, and closes off the end of the main bore of the carb at the choke end.

 

[Billh50]

We used to make our own insertion tools. Take a rod and turn the od the size of the plug. then use a drill about 1/16th under that to relieve the center. That will make it so you are tapping it on the outer edge so as not to straighten the plug during insertion. Then take a flat punch and tap the plug in the center to expand it.

To remove the plugs we just drilled center and used something to pry it out. or you can try and dome it the other way to make it smaller and fall out.