New used xj600 and need HELP!

I just bought a 1992 xj600. Here is the problem.
I bought the bike and it would start but not stay running. The night I bought it I managed to get it running just enough to take it on a ride around my neighborhood and came back to park it in the drivewway. Since then I have cleaned the carbs, got new plugs and changed oil. I could get it running every now and then until now. It turns over and might fire for a split second but nothing more. but then BOOM a loud backfire out of exhaust. It's done it three times. Havnt got it running in about a day and a half now. (it has been a lot colder the past two days too) What do I need to do next?

Thanks a bunch

-Josh

 

Not much to go on - have you got gas to the carbs ? Spark to the plugs?
Is the battery fully charged?

 

Yes I've got gas in the carbs, just cleaned them and I've tried spraying starter fluid in them. Got spark on all 4 plugs. But not sure how to tell if it's a strong spark. and I have been jumping it since the battery won't keep it's charge very well.

 

I put new plugs in yesterday and they already have kind of a lot of carbon build up on them, what does this mean?

It hasn't even ran since either, just turning over trying to start.

 

If they are black/sooty, I think it means you're running really rich, ie. too much fuel, floats adjusted wrong maybe or bad petcock letting fuel in in conjunction with bad floats. Open your oil filler cap and see if it smells like gas, if it does, drain the oil and change the filter, then take another look at your floats and petcock, that's what I"m doing now also. Hope it helps.

 

I tried sending you an email to your 'surf' address - bounced back

 

Could you email it to Padleout@hotmail.com.

I'll check my oil now and everything now. how would i fix the floats if that is whats wrong?

 

wow oil tank definitely smell like gas. Any pointer on what to do with this?

Thanks a lot guys, I feel like were narrowing down the problem here

 

Is the petcock on PRI(me)? Could be stuck floats in conjuction with the petcock setting

 

I would go ahead and drain the oil/filter, pull the gas tank off and put it over an empty container, check to see if it only flows with the petlock in pri position. Pull carbs, see the various posts via the search function, lots of good info on removal, teardown, etc. and don't give up! I'm doing alot of the same stuff so keep me posted on your status and we will both have great running bikes before you know it,

 

If its not on Pri then your carbs need "the whole nine yards" and then some.

 

I'm checking the valves out tomorrow and I guess do an oil change too. How long would it have to be set on prime for it to get this bad?

macros10, thanks man, I'm pretty determined on this bike so I sure as hell won't be giving up. I'll keep you updated on my project. I'd like to hear about yours as well

 

Cool, I'd say the prime would need to be on for several minutes or more, but the problem is that if the floats were working, they would rise to the appropriate level and stop, keeping any gas from flowing into the crankcase, which is why they say that the petcock and float problems typically go together if you have gas in your oil. I've changed my oil and filter, pulled the carbs and rebuilt the bowls/bottoms. Thought I adjusted the floats correctly but now I have fuel leaking from somewhere under the middle part of the carbs so I've pulled them off again and with the advice of others here, am going through it all a lot slower and more methodically. I want to be riding sooner rather than later, but like Fitz says, if you rush or take shortcuts, you'll just being doing it all over again, lol, so I'm trying to avoid that. Don't forget to put your location in your profile and the year/model/miles of your bike in your signature, makes it easier for people identify the bike and it's particular quirks.

 

I'll add all that right now, I got a couple test that I need to do and I think I should be able to figure it out, Thanks again man