Carburetor Problem

[Kinney]

Well today I took my carburetors off for the first time and cleaned them. What I found was problem. The PO must have busted a mixture screw in the carburetor and did a shitty job removing it. Can someone tell me what kind of problem this is going to cause me?

 

[xschris]

With a hole that big it's shot You will never get it to tune right.

 

[xschris]

With the 77-79 xs400 carbs the pilot mix screw needles don't have a stepped end like the 80-82 ones have. People over tighten there worn out needles and they break off and get fused into the carb. If they drill them out with a micro drill bit they can be saved but most often they use a huge standard size bit a mess it up

 

[Kinney]

That's what I figure. I was sick to my stomach when I saw that hole. Are there any aftermarket carburetors that will work on 78xs4002E?

 

[16VGTIDave]

I'm with Chris. The orifices in the carbs are precision machined. With that kind of damage, you will have a heck of a time adjusting the idle mixture, if you can get it even close. The only option I can think of is to try it. You only have some time to loose. I doubt that it could be repaired, but I've seen wondrous things done with JB weld. That may be an option. The challenge will be finding the correct drill to make a new orifice. Or find another set of carbs...

 

[Kinney]

xsChris, do you still have those carbs for sale?

 

[xschris]

No, but I will be listing a set off an 81 in a few days. I am just waiting for new bowl gaskets and passage plugs to come in the mail.

 

[Kinney]

Will those work on my bike?

 

[xschris]

Yep. If you run your bike stock there should be no issues ( no pod or aftermarket pipes and such) If you do you would have to jet them or put your adjustable needles from your carbs in them to tune them. The 80-82 sets have set jet needles the 77-79 are not. I don't rebuild or mess with the 77-79 carbs anymore because of the mix screw issue. I can't tell you how many sets where f*** up and had to toss them

 

[Kinney]

Chris I'm interested in those carburetors. Let me know when you are ready to sell them. My bike is all stock.

 

[xschris]

I will post all the pics and info in the classified section in a few days

 

[xschris]

I did notice that your bike has aftermarket mufflers on it. You may have to do some adjustments with these.

 

[Kinney]

I forgot the mufflers were aftermarkets. I'm looking to find a decent set of original mufflers or something close to them. The PO dumped the bike and broke the baffle out of the left muffler. Also they don't mount on the bike very well. If I was to buy new mufflers what kind of adjustments would I have to make to the carburetors? Are you talking about just adjusting the settings or swapping out jets?

 

[Scorpio1963]

Look on craigslist in your area for set of Harley soft tail mufflers,they sound realy mellow and sell for dirt cheap.They also slip on by using a sleeve.I have set on my bike I just installed recently and couldn't be any happier.

 

[Kinney]

Scorpio,

Are you talking about something like this

http://omaha.craigslist.org/mcy/4082954371.html

 

[xschris]

I have put the 5Z1 adjustable needles in it so that wont be an issue. I have drilled the pilots to 45 and will include a set of 145 mains as well as the 135 stock size. So I don't think you will have any issues with tuning if you do buy them

 

[Kinney]

Chris,

Consider those carbs sold. I get paid on Friday and I have a Paypal account. Pm me your information when the carbs are ready to go.

 

[xschris]

Pm sent

 

[Scorpio1963]

Kinney those would be loud you wont want those.These are what you want.

 

[xschris]

If yours are loose you can buy spacers that are made for that sort of thing. They are cheap