Carburetor Rebuild

[Bikebone]

I recently started rebuilding a carburetor for my 1980 xs400 and I'm having trouble getting the rod removed that hold the float in place. Any suggestion for a technique for removal??

 

[xschris]

You can use a fine edge from wire cutters/pliers to grab the end where the flat part is and pry them out. If the flat part is too close to the post a knife with a thin edge can be used to pry it out. Then use the pliers to twist/pull it out. Remove any gum or varnish from the area first and use a good penetrating oil on them as this will make it even easier.

 

[buztabuzt]

Mine were stubborn but I used a small Allen wrench with some light hammering in conjunction with Chris's suggested pliers / wire cutters to pull...

Worst case p b blaster to free it but make sure to keep anything sensitive like diaphragms clear of it?

 

[Bikebone]

Thank you guys for the reply. I used both suggestions to get the pins far enough out so I could get a needle nose vise grip in conjunctions with light hammering to dislodge the pin. Unfortunately I bend the pin and will end up making a small purchase.

 

[xschris]

Avoid any tapping or hammering as this can and will break the posts. I have removed dozens of these over the past 20yrs and never had one break. If you replace the pin with ones from the 70-79 bs38 carbs used in the xs650 or the ones used in the 76-77 xs360 they will just slide in and out. They don't have the thicker end that locks them into place. I use those on all my bs34 xs400 carbs. Never have to worry about getting them out again.

 

[Bikebone]

Xschris,

Obviously you know carburetor, what is the best rebuild kit for the 1980 xs400? Any advise for cleaning would also be appreciated.

 

[xschris]

I soda blast all my carbs. I don't buy kits. I buy parts as I need them. Gaskets, o-rings or any rubber parts is usually all I need most of the time. OEM stuff or mikuni jets are a must as the china made stuff has quality issues.

 

[Bikebone]

Sorry for asking many questions. I removed the jet above the emulsion tube. From what I've seen the emulsion tube should slide out toward the top of the carb. The tubes are not moving, and afraid to apply pressure. Are they critical to remove and clean?

 

[xschris]

Yes you need to remove them. Screw a bolt into them where the main jet was and tap them out. Use some cleaner then some lube then they should come out.

 

[Doug Smith]

Avoid any tapping or hammering as this can and will break the posts. I have removed dozens of these over the past 20yrs and never had one break. If you replace the pin with ones from the 70-79 bs38 carbs used in the xs650 or the ones used in the 76-77 xs360 they will just slide in and out. They don't have the thicker end that locks them into place. I use those on all my bs34 xs400 carbs. Never have to worry about getting them out again.

I found that out.....bought a replacement float assembly and the new "pin" wouldn't not seat when installed....loose as a goose.
I reused the old pin.

 

[xschris]

The earlier "loose" type pin work find and won't fall out as the bowl keeps them in place. The 70-79 xs650 carbs and a lot of the 70's mikuni carbs used them. The later ones that "fit tight" I think where made like this to make user/owner working on them harder to deal with and taking them to a dealer more possible. Kind of like capping the pilot mix screws and plugging the bolt hole to the tci pickup cover. I have been running the old style pins for many years and never had an issue. I also use genuine mikuni pins/parts.

 

[Doug Smith]

I was surprised how relatively inexpensive the genuine Mikuni Parts were.....only a few more dollars and definitely will fit!
Much of the aftermarket stuff around is questionable quality at best.
I steer clear of "generic" Chinese parts.