If you’re up for it the people on the forum will get through cleaning your carb. It was not that long ago that I thought spraying carb cleaner into the throat was a tuneup. If you go through one then you can do most any carb in the future.
Welch plugs are mysterious and that’s all. The plug comes out by piercing the plug and prying it out, clean in there and press in a new one. No special tools. There’s just holes in there so nothing special. If you have a sharp chisel it makes it easy. The Welch plug area is often mentioned when troubles persist after cleaning but the chances are about 80 or 100 to 1 that it is. About the only time the Welch area would be a problem is if the carb has metal rot especially the white aluminum crud buildup but at that point the carb is often too far gone to bother with. It’s very rare to come across a carb in that condition. So the upshot is forget Welch plugs.
Cleaning is fairly straight forward and remembering where things went. Taking pictures with a digital camera helps. A big problem is remembering how the linkages were setup before taken apart. But they can be noodled through, as in there are only so many places at either end of a spring, governor rod or throttle rod can go.
I’m no sure which model 8hp you have but there is probably no spring to remove, a long rod between the governor arm and throttle and another from the governor arm to the throttle plate on the carb. There’s only a couple of choices for holes on the throttle and throttle plate. My be you know where those go so no issue.
The bowl comes off by the bottom nut and there’s a needle going into that. The needle has a metal washer, a rubber gasket ring and a spring. The nut has a few holes depending on the carb but usually one or two larger holes near the base, one or two higher on the flat between the threads and one inside. All those are prodded with a stripped tie wrap, sprayed with a carb cleaner and washed out with air. If you don’t have air that’s ok. The high pressure of the carb spray is enough.
There’s the low idle needle which also has a spring, metal washer and rubber gasket. Back that out and spray in there with carb cleaner.
On the bowl side of bottom of the carb there float on a hinge with a needle attached to it with a clip. Pull the retaining rod out and remove the float, clip and needle. Put all these parts and the ones above into a cup or dish.
Up in the area where the needle went is a rubber seat for the needle. You can pull the seat out with a tool that has an end like a crochet hook – it has just enough of a dull barb to catch the far end of the seat to pull it out without tearing it. You probably don’t have one and for the first attempt can leave the seat in. If things are weird after cleaning then you can get the seat out with a thin pick. There will be a replacement in a kit. The seat goes in ring side in first – one side has rings the other does not. By the way least for me kits are expensive and useless. The metal parts are not needed and the gaskets iffy on most rebuilds. For a cleaning I usually put in new o rings on the high and low jets, a new bowl gasket and a new seat. Since you can’t get seats as a single item they come in packs usually with a needle so I put in a new needle also but they are almost never needed. Packs usually come with seat, clip and needle, or those and an a bowl gasket. Gaskets I buy by the 20 pack or from a hardware store. Those are all that’s needed for rebuilding a carb = seat, 2 O rings, bowl gasket, needle.
There’s a few places to prod in the carb.
1. 1. The flat on the outside of the carb ½ in to the right above the low idle screw. That’s the air vent. Prod in there with the tie wrap. Spray into the square hole on the bottom of the carb by the bottom Welch plug. You should see spray come out of the hole on the flat.
2. 2. Spray in to the hole where the gas line was attached and spray should come out where the needle went.
3. 3. But some Z bends into the tie wrap and push it up into the center post which holds the emulsion tube. Spray in there and look into the throat to see if the full spray is coming out. If you look in through the bottom of the tube and put the throat in bright light you can see light through the tube.
4. 4. Prod the holes inside the throat. Depending on the carb there will be 2-3 holes close together opposite the outside Welch plug. Bend the tie wrap.
5. 5. If there’s a vent hole by the base of the butterfly prod there and spray.
6. 6. Your carb may have a hole(s) up higher to the right or left side of the butterfly, prod in those and spray.
7. 7. Spray into the primer port, there the thin line ran to from the primer bulb. Spray should come out from below.
8. 8. Unless I missed something that’s it. I usually dip all carbs overnight before the above but that’s not essential.
Assembly:
1. 1. Put the spring, washer and gasket on the high speed jet.
2. 2. Screw the jet assembly into the nut.
3. 3. Put the spring, washer and gasket on the low speed jet.
4. 4. Put the bowl gasket on the carb rim.
5. 5. Put the clip on the needle and set it on the float tab.
6. 6. Put the float in place and insert the rod. Check that the float is parallel with the rim. That should work out to 11/64 ths. If there are problem running later this may have to be revisited.
7. 7. Put the float on with the rod.
8. 8. Put the bowl on with the nut and high speed jet attached.
9. 9. Screw in the low speed assembly.
Mounting the carb:
1. 1. Install the throttle to governor linkage rod, probably not removed.
2. 2. Install the governor to throttle linkage rod, governor arm first then into a throttle plate hole. As you look at the carb it usually be the hole to the left on the far side.
3. 3. No springs on yours I think, they stayed on.
4. 4. Press on the fuel line and clip.
5. 5. Attach the primer line.
6. 6. Attach the carb to the block. By the way it’s usually easiest to remove the carb with the manifold inplace rather than at the manifold carb bolts.
I probably missed something but that will likely get you a start and several years of reliable operation from the carb.
