New XJ Owner

Just picked up an '86 XJ700XS that spent the last 5 years in a barn and need some advice. The bike is semi assembled with the gas tank fenders and side covers in the paint shop. All the fluids have been changed I decided to crank it up the other day so I bought a fuel filter and a small funnel. The bike starts in choke but won't stay running if I try to move it out of choke. I know the carbs had been off the bike for some work but am not sure what was done and if they were bench tuned. Anybody have any suggestions?

thanks

 

Yup, pull those carbs and clean them out. After sitting a long period (sometimes as little as a month or two), parts and ports start getting gummed up and blocked. Assume the worst and start from scratch. Pull 'em and scrub them out. Rick-O-Matic has a great How-To on this evolution and you should have no problems. I'll bet dollars to doughnuts your non-choke idle problem will disappear. Let us know where you end up and could you please insert where you are located in your info. If you are near someone, odds are pretty good they would be more than willing to pop by and give you a hand. Welcome to the gang.

 

Thanks for the reply Robert. I've spent several hours on the forums since the post and had a feeling you(or someone else) was going to say just that. It has decide to snow again here in the Cincinnati area so taking the time needed to clean the carbs won't be so painful. I guess I should have included some more info on my first post but forgot to mention so here goes. The previous owner had already taken off the gas tank so I have no idea what some of the hoses connect to. I assumed the line between the #2 and #3 carbs was the main fuel line that connects to the petcock and the vacuum line off the #2 or #3 intake(not sure how they are numbered) also connects to the back of the petcock. The 2 lines between the outermost carbs connect where? Do I need to plug them when trying to start the bike w/o the tank on. I ask because there was fuel coming out of the one on the right side of the bike when i attempted to start it.

Anyway, thanks again for your support. Can't believe I found you guys! Not sure what I would have done w/o the wealth of info here. I'll keep you up to date with the progress and take a few pics along the way.

Tweezer

 

Welcome aboard Tweezer!
I guess I can't say anything that hasn't already been said, other than - if you need info on a particualr topic, try the "search" function. You'd be surprised that alot of others came across the same problems as you have, or will in the future. PD

 

Great site here with lots of great info. I'm still reading up on some old threads.

Sounds like you got yourself a great find too.

 

Yes and yes. The vacuum line comes off the #3 carb intake manifold nipple (although it really doesn't matter which one you use, as long as the other three nipples are capped off).

The cylinders are numbered 1-4 sequentially starting at the left side (clutch lever side) of the bike.

Those lines "go" nowhere....I think. This has been an ongoing mystery for some time, as the Yamaha service manual and "hose routing" diagrams aren't very explanatory on this subject. Those are bowl vent/overflow passages and hoses, and many people believe they just head straight down, towards the ground, about a foot in length. By the way, they are bigger (5/16" ID) than the fuel supply hose from the petcock.

Having fuel come out of one is not a good sign....they're supposed to vent fumes, not fluids! Stuck float needle, or float, or ????

By the way, if it's a "California" model bike, then you also have some type of vapor recovery cannister thingy that absolutely no one knows how it's hooked up........

And an anti-rollover check valve somewhere on the bike, with god knows how many additional hoses to that.

 

first try at posting a picture. It's HUGE!! I'll have to work on that next time. Anyway, as it turns out the leaking fuel i described earlier is coming from the base of the posts kinda near the funny looking arrows. (need a good program for photo editing for mac)



Any ideas why it would be leaking fuel from there?

 

did the float valves get replaced? Have the floats been properly measured for required height?


If not, then it's quite possible you're leaking past the valve, or your float height is way too high.

 

More than "quite possible". I'd go with - Almost certain -

 

Unfortunately I have no idea what was done to the carbs other than the seller said they were "cleaned". As it turns out the person "cleaning" them has little or no experience with these carbs which leads me to believe he probably did more harm than good. I think it's time for the complete rebuild so I know what I've got when I'm done. I'm going to have to learn patience now :x

thanks guys

 

Tweezer,
It's not as bad as you may think. I lay a nice clean towel on the bench in the shop to be able to keep track of all the parts as I remove them (and soaks up fluids that may leak out) A small container (plastic Tuperware works good) is helpful to put the small parts in, so you don't accidently knock them onto the floor. Lay out every part in the order it comes out so you don't get confused when it comes time to assemble them again. And like you said, patients always helps. Good luck! PD

 

thanks pd.