Never give up on Old 8 hp Briggs Carburetor

DTurner

Member
I write this a help that you don’t make the mistake I did.
You have to get the jet out in order to get the carburetor apart .
I refuse to give up on this carburetor. I used a wide blade screwdriver , and it damaged the threads in the base bowl of the carburetor trying to remove the jet. So i took and old screwdriver, and ground it down and widen the blade as to not damage the slot in the jet. As i did try to get it out.
Screw the jet back down. Went to hardware store and bought a cheap metric tap 8mm x .75 mm pitch tap . I retapping the bowl with jet seated to depth. Then used the special screwdriver and back out the jet, and disassembled the carburetor.
So don’t make this mistake . If you do this what I did to get it apart.
Hope it’s helps, to someone that doesn’t know these carburetors.
 

Attachments

EvilDr235

Member
I have been using a replaceable screwdriver bit. One of those 1/4 inch drive bits that has a thicker non tapered tip. The bit I use is about 2 inches long and fits the slot with no slop and does not try to cam out when you crank on it. Some penetrating oil first is a good idea. I have been lucky that most came out easy. I did have to drill one and use a PROTO brand square easy out to remove it. I have gotten a lot of good tips watching ZippoVarga and Mustie1.
 
Last edited:

gdstew

Active member
B & S has 2 sizes of jets. The small bowl uses a 1/4"-32 NEF tap and the large bowl uses 5/16" - 32 NEF. I also recommend the proper screwdriver 19061 and 19062. You can also get the set of taps 19245 ( might have to recheck this number )
 

DTurner

Member
B & S has 2 sizes of jets. The small bowl uses a 1/4"-32 NEF tap and the large bowl uses 5/16" - 32 NEF. I also recommend the proper screwdriver 19061 and 19062. You can also get the set of taps 19245 ( might have to recheck this number )
Good point 5/16 -32 looks better now that you mention it
 

K-Tron

Active member
Once the threads are damaged, thats about it for those large flo-jet carburetors. In this day and age, it takes three, to five flo-jets to build a good one. Most of the time those threads are all but stripped out. You might have damaged yours more than anything using the wrong tap. They are indeed 5/16-32 thread.

Chris
 

ulgydog56

Member
yup... almost screwed my flow jet up by not taking the main jet tube out...:bonk:
 
Last edited:

Motormowers

Subscriber
Prob the worst carb Briggs ever made. They leak more often than not and the new ones are made in China and not worth the $150.00 Briggs wants for them as I've had several leak right from the box and Briggs' excuse was to send Teflon washers for the emulsion tube instead of replacing the carb. I've bought the knock offs as little as $15.00 on Ebay with as good if not better luck than the Briggs OEM carbs. Those brass tubes fight you even with the Briggs tool to extract them as they are so tight the chew the slot up anyway.
 

DTurner

Member
Well I put back together and now I found that the carburetor upper housing is warped . Wish I read this chiltons about how to check , this before bought the kit .
Let you know what else I find .
 

Attachments

Last edited:

Steve Kunz

Subscriber
I have a Briggs carb. that has the upper tube part of the jet broken off in the carb. I guess someone tried to get it apart without taking the jet out. I don't know if it can be drilled out or not, has anyone ever tried drilling one?
I found a different carb. and used it. I was going to try drilling it sometime but never got around to it.
 

DTurner

Member
Well was not pretty but I carefull applied a bead of #2 permatex to the surfaces . I made sure to look and clear the idle circuit, so permatex would not block it. Reassembled the carburetor and put back on the the motor. It started and idle which it never did before. The main jet needle needed slight adjustment. Ran much better , than I ever expected.
Vacuum leaves 🍁 with the billy goat all afternoon.
 
I noticed that nobody mentioned heating the carb up to operating temperature before trying to take it apart. Maybe laying on a black surface in the sun, or putting it in a toaster-oven on low heat.
Also with the British Amal carbs used on their old motorcycles the mounting flange is often warped and some mechanics make a tool or jig that pulls the carb flange against a surface curved the opposite way it is deformed, putting slight pressure on it while they heat the carb body gently in an oven to get it to go back into shape.

Double gaskets between the carb and manifold can help seal a slight warp up too.
 
Top