258 with a miss

[jb8376]

I recently changed the plugs wires cap and rotor and it was running pretty smooth. I ran it out of gas and after filling it back up it starting running rough. So I figured I stirred up trash that was maybe in the bottom. of the tank. I pulled the carb which is a carter bbd. Well it turned out was pretty dirty . I soaked it overnight and rebuilt it. I did not think to check the float adjustment till after I put it back on. Now when i start it up cold it runs a little rough like it is not firing on all cylinders. It blows out a little white smoke until it warms up and then it smooths out except for a miss. The miss is at idle and you can feel it a little when you accelerate. Also it will puff a little black smoke when you rev it up. I don't get it. It did not do any of that before the carb rebuild. Any suggestions would be appreciated. Thanks

 

[Tinman22]

That's my favorite myth. The one where running your car out of gas either sucks up or stirs up the stuff on the bottom. The pickup tube is always at the bottom of the tank. Any way it sounds like there are two issues at once 1 the miss and 2 the smoke . The miss first recheck your work I.e. plugs cap wires and the like. My guess is that you will find a fouled plug from incorrect carb. Settings hence the smoke. It will be the wet one.

 

[jb8376]

I just pulled a couple of plugs and they are covered with black soot. Looks like I am going to have to pull the carb back off and get the settings right.

 

[Tinman22]

Sounds like a good idea. Was your choke open all the way?

 

[jb8376]

Yes I have it working good with a new choke pull off.

 

[Torxhead]

Another thing you could do is remove the gas tank to clean it out. It is a lot of work, but you have 30 years of in there. Also you can check the condition of the fuel pickup sock and adjust the fuel sender settings to the gauge if you need to. I hope you have changed out the main fuel filter out since running out of gas.

 

[jb8376]

I had changed it shortly before I ran it out of gas. I did not think about it since it was new. I will go get a new one.

 

[Tinman22]

Fuel pickup is always at the bottom of the tank. Unless your 30 years of has been floating. running it out of gas will not cause an issue. I just changed tanks in my 1991 f350 diesel the pickups are 1/4 - 1/2 an inch off the bottom and the tanks were clean. since the pickup tubes are at the bottom they are always sucking up the on the bottom. Otherwise the bottom of the tank would fill with, well mostly water, at least up to the level of the pickup tube. Filters are there to collect the water and sediment that the pickup picks up off of the bottom of the tank. A lot of times people will associate (incorrectly so) several events and then go about trying to fix a phantom problem while skipping the obvious.

 

[johnnyreb]

mine does about the same thing cold. Runs rough, misses, runs rich till it warms up. I have a MC 2150 sitting on the bench for it.

 

[jb8376]

Well I got her running good. I pulled the carb and checked all the settings. The float was good but the metering rod and accelerator pump needed adjusting. I should have done that to begin with. Thank you all for your help.

 

[Tinman22]

Got to love the easy fixes. And new knowledge is priceless,just don't forget where you put it.