Nikki Dual Carb Main Jets

[GAVolunteer]

Briggs V-Twin
Model 44M777 0148 B1. SN 081212YG
On a John Deere Lawn Tractor

Engine has a Nikki dual carb. When I removed the bowl, both main jets fell out. They look identical, but it turns out there is a Left and Right main jet and they are different. There are no makings on the jets. Does anyone know how to determine which is which?

Thanks.

 

[Fish]

So they are just pressed in? I looked, and have no help, sorry. Never have liked a Nikki carb. Are there any markings at all on the jets???

 

[GAVolunteer]

So they are just pressed in? I looked, and have no help, sorry. Never have liked a Nikki carb. Are there any markings at all on the jets???

I do not like Nikki carbs either. Yes. They are pressed in. But the o-rings are so small, they have a tendency to fall out as the o-ring gets old. Here is a link to a site that has a lot of great pictures. http://outdoorpowerinfo.com/repairs/briggs_intek_v-twin_carb.asp

The jets are very small. I have yet to find any kind of markings. I assumed there was some way to tell them apart, but I have not figured it out.

 

[roeroe]

Supposedely there are markings on the carb itself telling you which goes where the numbers are very small and require a magnifying glass to see. I have included a video that explains rebuilding and shows how to find these numbers

 

[StarTech]

Left jet is 1.18mm PN 792296
Right jet is 1.22mm PN 842627

So if you have 3/64 drill bit you can figure which is which as it won't go in the LH jet but will go in the RH jet; unless, the LH is badly worn.

Btw those o-rings needs replacing at least.

 

[Hammermechanicman]

I use a cheap otoscope. I can tell the size difference by looking at them side by side. If you do get them reversed it's not the end of the world. Some engines run just fine and some one cylinder is a tad rich

 

[bertsmobile1]

I regularly replace the smaller one with a big one
The mower actually runs better like that
The different jets are to keep the EPA happy not to make the engine run better

 

[GetTechnicalWithJd]

Use a magnifying glass to read the 3 digit number on each jet. The jet with the higher number goes to the Right. (There is an "R" and a "L" embossed in the casting on the top of the carb)

 

[StarTech]

Not always there even on new jets as they figured we knew how read them and make mixture adjustment as needed. I tried getting techs to help me build a cross reference chart of PN to size but they all were too darn lazy to help so all I got is a chart of the ones that I used which is limited in scope as I seldom change out jets but I do lose one every now and then.

This what I got for trying help anyone out on these.