Another quick carb question

[wylie coyote]

Okay- hopefully just one more. I'm putting in the carb kits as we speak, (Ain't it nice to work night shift?) and I noticed where the pilot jet goes, there is supposed to be a screw to plug the access hole (?), according to one of the tech articles, or in my case on the 80, there is a smooth bore above the pilot when it is screwed in. Now- in the kit, there is a disc that just happens to look the right size to plug that hole. Is that where it goes? Is it a gotta do thing? Nothing was in there before. How would you get the plug out once you get it in? (No way to grab it, I would guess). Thanks

[wylie coyote]

I think I realize what the deal is all of a sudden. This carb is a direct feed to the pilot, instead of the passage fed, where the end of the hole would have to be capped. Sound good?

[DGXSER]

Yes, there are two "pilot" jets/srews referred to in the carbs. One is the pilot idle jet or pilot jet that is accessed through the carb bowl. The other is called the mixture screw, or the pilot mixture screw, or the pilot idle mixture screw or.....anyway, it is on the front top of the carb. On the later model carbs like your 80, it is down inside a tower. From the factory, these towers were capped with a disc like you have in your kits to keep owners from messing with the EPA setting of the mixture. I do not know anyone who puts them in after rebuilding the carbs.

On the older model carbs (and on some very rare 80 model carbs) there is a passage link from the main jet tower to the pilot jet tower. On these carbs the main jet is bigger, typically a 135 or 137.5 or so to feed the pilot jet also and thepilot jet tower is capped with a screw. Not the disc you described.

Hope That Helps.

[wylie coyote]

gotcha- thx

[wylie coyote]

Okay- I found another bad o ring on #4 idle screw, everything was clean, gonna bench set everything for now. Replaced the bad idle screw, started with them 2- 1/4 turns out for now. Nothing else looked iffy.
One other thing was the jetting was 110 across the board, instead of the center ones at 120. Sounds like some do it, some don't, the factory does (the 120 on# 2-#3). Apparently the PO didn't.

[wylie coyote]

Also- one other thing that isn't quite clear at this point--- when you measure the float setting, is it measured from the base of the carb body with, or without the gasket? i.e., measure from the gasket (metal) surface, or the surface of the gasket after it is on the carb body? thx

[TADracer]

Measure from the metal gasket surface with no gasket in place. Measure to the top of the float but do not compress the needle valve spring while doing this.

[DGXSER]

The factory put the 110s outside with 120s inside on the earlier versions of these carbs, and in some specific locations perhaps. Almost everyone I know of jets them consistantly across the board. I know do on all of the carbs I work on and they run great like that for me.

As to the float, as stated, measure from the metal gasket surface of the carb body, no gasket in place. Measure to the highest part of the float, whatever that may be. I use an old credit card or hotel room key to make a "go-no go" gage. Skids or one of the other older fellows here advised me on that some time ago and it works GREAT!! I really like it. I cut one side to the max heght and one side to the min height. A total diff of 1 mm. As long as the float hits the min and misses the max, it is good to go.

[CatatonicBug]

there is a disc that just happens to look the right size to plug that hole. Is that where it goes? Is it a gotta do thing? Nothing was in there before. How would you get the plug out once you get it in? (No way to grab it, I would guess). Thanks

That disc is meant to go into the top of the fuel/air mixture screw tower. Most folks don't use it. The factory put them in to prevent owners from messing with the fuel/air mixture screws. You have to drill them out to remove them, so they are more annoying than anything.