A silly questions abou carbs

I'm cleaning the carbs of my 1986 xj700 and I tried to remove the main jet but it turns and doesn't come out. Is that normal or you thonk the thread is stripped? all four are in the same condition.
the pilot jet comes out easy.
thanks for the help in advance.

 

Not normal, they should unscrew and come right out. See if the main nozzle is turning when you try to unscrew the jet. Sounds like you will need to replace the main jets and nozzle(brass center of carb, it sprays fuel into the airstream). The main nozzle should have a locating pin to keep it from turning and to locate it proprely in the carb body, sounde like it is broke.

 

do you have some pictures of this components?
I will check the carbs tomorrow when I get home.
thanks

 

That locating pin will only keep the emulsion tube from spinning if it's seated in all the way... Once it backs out even a little bit, it will spin. So maybe just reach in from the top and push the emulsion tube in with your finger as you loosen the main jet. You will have to remove the slides to get to the top if you haven't already...

 

you will see the top of the emulsion tube (a.k.a. nozzle a.k.a. needle jet).. The locating pin is inside the carb body, which you will not see until the tube comes out.

Basically, the main jet is screwed into the bottom of the emulsion tube. Once you loosen it a bit, the tube will start moving out of the carb body, at which point the locating pin is no longer holding the tube. The fact that this is happening is actually good -- that means that the tube is not corroded and stuck. Some of us had to struggle to get the darn things out so they could be cleaned.

Speaking of.... Once you get the tube out, you will find a multitude of tiny holes drilled through its sides. Make sure they're nice and clean, along with the main bore inside the tube.

 

thanks stereoman! I can wait to get home and put my fingers on them.
I'm not sure if the carbs are Hitachi or Mikuni. Are they have the same design and parts?

 

Same basic design - there are differences in the floats and the enrichment circuit but they work the same.


Chacal carries parts for both - just PM him on this site. He has fair prices and great advice, ships fast and has the stuff in stock most of the time.

 

How can I find out which carbs I have?

 

Well if your bike is an XJ700 Maxim -X they are Mikuni. One way to tell is look at the enrichment circuit. On the Hitachi they are pins that are pulled up when the "choke" is applied. The Mikuni's slide side to side. There are probably other ways to tell bu that should be the easiest.

 

Mikunis usually have MIK or MIKUNI written on them. Hitachi carbs have a little compass symbol.

 

They're Hitachi's. Thanks a lot guys. I will try to take pictures once I put them back on.
thanks again to you all.