I've been helping a friend get a 2000 model Trailblazer up and running after sitting up for two years. It appears that he had an ETC problem initially and didn't know about it at the time...so he left it sitting in his garage for a long time.

Well, I decided "hey, lets get this thing running"...that's usually where the problems start.

Got it to firing after adjusting the ETC...but not getting gas....hmm.

The carburetor was seriously "gunked" up. After letting it sit in carb cleaner for about three days, it was a beauty...every thing looked great. The floats were free. It looked new.

I proceeded to put everything back together...It cranked on the first try. Cool!.....not. After I turned it off and let it sit there for a few minutes, I noticed that gas was coming out of the overflow tubes....AND IT WON'T STOP! I have to turn the gas off to make it stop.

I've checked the needle...it's in great shape. It appears to be going into the Jet properly...I can't see any trash.
The floats appear to be free and moving easily.

I'm not sure what to do....I read other posts that mention adjusting the floats...??? how in the world would you do that? It doesn't appear to me that you can adjust them. Can you adjust the float arm?

I'm at a total loss...Can anyone help? Any ideas why gas would flow into the carb like that? My first thought is the needle isn't seating properly (but that's just a guess).

Any help would be greatly appreciated!

 

you have to bend the float where it touches the needle valve it is not stoping the gas soon enough. the other thing it migh be but not sure is maybe what you use as the cleaner eat awat the seal on the needle? just something to check

 

My guess is the little rubber washer/seal has been ate away from the carb cleaner........could be the floats too I guess.......

 

How would I replace this?....order a kit to rebuild it, or order would the jet be included in that?


Also, if it is the the needle valve, would I bend the float arm down so that the floats would engage the arm sooner?

 

The bottom of the needle is sitting on a small metal tab that is part of the float. As the float raises, this tab raises, and then the needle is raised. You GENTLY bend this tab to adlust the float height. Bending the tab UP, LOWERS the fuel level.

To check for a bad rubber washer, remove the carb bowl (leave carb on engine if possible), open fuel petcock, and manually lift up on the float--fuel flow should stop when the float reaches it's maximum upper limit. I would try this first, as this seems to be the most logical cause of your problem.

 

ok...got that straightened out, it was a piece of trash keeping the needle valve from working right.

Well, I got it all togerther and it will crank fine...however, it will not idle. I've adjust the idle screw and air screw but it doesn't make a difference...it will not idle.

If I barely press the throttle it will bog down....as I press more, it will rev on up. If I let off, it will go dead.

Any ideas.

 

i hate to say it, but you just cant throw the carb in cleaner and thats it. you have to blow the passages out and check everything. chances are you have crap broking the idle circuit. remeber the piolet jet is for closed to around 1/4 throttle.

 

Thank you...I'll take it off an blow it out. We'll go from there.

 

you will need to at least pull the low speed jet and make sure its clear. Its the smaller of the two and plugs easily.

 

You were right..the pilot jet was stopped up.

IT WORKED GREAT!!!!!


I would like to personally thank each and every one of you...this has been a lot of fun and I have learned a lot about carburetors.