• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Rough idle followed by no start after oil change.

  • Thread starter Thread starter Zack
  • Start date Start date
So what your saying is when you first pulled the bowl drains it had fuel in it but now they won't refill correct? If that is true you either have a pinched fuel line between the tanks and the carbs or something stuck in the line somewhere. If you are getting fuel to two of the carbs but not the other two the problem is most likely in the carbs themselves. You do have the fuel line hooked up to the correct place on the carbs right? There are two vent lines for the bowls they are between #1 & 2 carbs and #3 & 4. The fuel inlet is between #2 & 3 carbs on the airbox side of the carbs. That is where the fuel line hooks up.
 
main fuel line is off, and not clogged but the T it goes into is very dirty looking into it with a flashlight.
How might I take it off so I can clean it?
ALSO, the float pins are all being very stubborn and will not come out so I can check the float pendulum hole thingy.
 
You probably found your problem. You have to ungang the carbs to get the fuel "T" out. If it hasn't been done recently it would be a VERY good idea to strip the carbs and dip them in carb cleaner for 24 hours. Blow out all the passages with compressed air and follow that up with all new orings.

You have to be very careful with the float pins because the little cast posts on the carb body break very easily. What i do is put a small socket on the side of the pin that has the flange on it and put it down on a table to get some support on the bottom post. Then tap VERY VERY carefully on the other side with a small roll pin punch and a hammer. Once it starts to move out you can grab it with a pair of pliers and pull it out the rest of the way.
 
Ungang them, I was afraid of that.. Are there any good youtube videos of that? I mean I have the bowels, slides etc all out but the carbs look pretty well "ganged".
I managed to get one pin out by using a dike, going to have to use my impact driver when people arent sleeping for the float screw, its stupid tight like most else.
I was hoping to just go heavy with the carb cleaner in the "T" and then hit it with air once its soaked and I have the floats all off, is that reasonable or worth the effort or am I going to have to ungang them 0_0
Ive come this far on youtube and prior dirt bike carb knowledge lol
 
You cannot take shortcuts; there are passages you cannot see that can become clogged and cause you problems. Go to Basscliff's site (http://members.dslextreme.com/users/bikecliff) and download the carb rebuilding tutorial by Nessism. Follow his step by step instructions to the letter or you will have to do it again. Get new orings from www.cycleorings.com and bowl gaskets from Z1; I would also replace the screws with allen headed ones.
 
Here is some you tube videos if that will help.

https://www.youtube.com/watch?v=MdfH_kodoSU

https://www.youtube.com/watch?v=HrfV0kN1AQA

https://www.youtube.com/watch?v=Z4VJHvqB9F0

It is a 3 part series and they do a great job of explaining the process. They take them all the way down to the bare core but you don't have to remove the throttle shafts if you don't feel comfortable. Most guys here just leave the throttle shafts and butterfly's in and remove everything else and dip them in carb cleaner.

Your going to wanna get a couple cans of aerosol carb cleaner and a gallon can of carb dip. You will also need some source of compressed air to blow through all the passages with. If you don't have an air compressor those cans of electronics duster like for your computer work just as well. Just take your time and do it right and you will be fine.
 
unless i am misunderstanding something, you did NOT have the vacuum line connected from the carbs to the petcock. this line is needed to make the fuel flow in the "on" position, which would explain why the carbs were dry....yes, you probably need to clean the carbs, but dont overlook something obvious and easy.
 
A 1980 850G that runs perfectly will not start from cold without choke. At least not within a reasonable amount of cranking. Without the choke cable, you can pull the choke rod on the carbs to the left, and hold it. You may be able to put a clothes pin on it.

Your petcock has two connections. That means that you need to connect two connections. The smaller one is engine vacuum, which opens the valve. The other is the fuel flow. Fuel should still flow when you have the petcock on prime, but when you leave the vacuum connection off, it isa giant vacuum leak, which isn't good ever.

If this bike has been sitting without being stored with the carbs drained, you will have to clean them internally, including the emulsion tubes and all of the tiny internal passages. There isn't any debate about that.
 
the float that I took off doesnt move the same as the others now.
The others you can gently push and feel it compress, but this one swings freely for the most part now.
Also the screws on the bar that holds the carbs together wont come off even with my impact driver, at this point I may have to just conan it with the carb cleaner and hope for the best.
I dont think those screws have come off in 44 years..

EDIT Testing by pouring carb cleaner into main fuel T I get dripping out of all 4 carbs, with the strongest stream in carb 2 and 3. Those are closest so that makes sense. If I spray it hard it will come out of all 4 so I think we are good to atleast test it. Fuel is able to get to the bowels.
 
Last edited:
Zack said:
Hello, so after a lot of work I was down to my last few things that my 1980 GS850 needed.
I drained the horrible oil last night and let the loctite for the drain plug to set overnight. I also changed the oil filter.
This afternoon I put new oil in ( a little over 3 and a half quarts of 20w50 valvoline) and a new choke and clutch cable.
After everything was back together and tight I started the bike, and it would not stay on without some choke or throttle and then proceeded to die after a few minutes.
It wont start for anything now and makes a noise I haven't heard before..
The bike was NOT started before I had the new oil in.
I'm at wits end here, after everything the last thing to do before I could ride it and now it wont start!
It started fine with the old nasty oil, sheesh..(wasnt ridden but would start and idle fine)
I'm hoping it's something stupid but I haven't figured it out yet. Please help :([/Q

Am I the only one that caught that?
Click to expand...
 
Might be an obvious suggestion but................... Is your vacuum pipe for the fuel tap (petcock) ok. If it's off or split this will give you a strange noise (air puffing) cause strange running and the bike will stop running when the carbs run out of fuel?
Colin
 
You must log in or register to reply here.
Back
Top