carb rebuild

[Horse]

So, remind me again the primary signs that your carb (a carter bbd) needs a rebuild.  I want to make sure that's what my fuel delivery issues are before I send it to the carb guy, since most issues outside of that (with thanks to the tutelage this site has offered) i can do myself.

[Whuntmore]

might also consider running a can of carb cleaner (and some fuel cleaner) and see if that don't fix it first.

[Horse]

yeah I've got the carb spray, haven't hit it with that in awhile.  I have to prime the carb with gas when she gets low on fuel.  When run out of gas I'm used to dropping a little into the carb, but when there's gas in the tank she still wants some dropped in the carb.

[Whuntmore]

what's wrong with your fuel pump?  is there some seal loose between the fuel line and the carb?

Maybe your carb does needs a rebuild.

[BenM]

There's a bad idle issue that can be clogged idle tubes. It can be cleaned up with a small drill bit by removing them without taking the rest of the carb apart.

If you're so inclined.

[Horse]

If there were a seal lose, wouldn't I be leaking gas?

[Horse]

Yeah, I'm not even starting.  There's only a gallon of gas in there and she hasn't been starting when the tanks that low.  Throw a fresh gallon in the tank and a little in the carb and she'll start; that's how the last week has been going.  When I'm able to put half a tank in then everything runs more or less fine. This all sounds to me more like fuel pump than carb rebuild.  Bad idle has always been the give away for a rebuild as far as my experience goes, and once warmed up (she runs very cold) the car idles fine. 

[carnuck]

Could be the pickup tube in the tank has rotted or the hose from the tank has become a piccolo from MTBE

[Whuntmore]

Could be the pickup tube in the tank has rotted or the hose from the tank has become a piccolo from MTBE

Now that Carnuck has mentioned it, that's about the only thing that makes sense.

[carnuck]

If the line is rusted and you apply air, what's left may blow off into the tank leaving you stranded right where the car sits. Never work on your car in a spot where you have to move it if things don't go right!

[Horse]

pickup tube inside the tank?  That's something I didn't know about.  The gas line is rusted but not leaking from what I can tell.  The PO proudly called the car "stock" so I'll bet that's the original tank.  This air compressor business... you just blow air down the gas line?

[milliard431]

Those pick up tubes are metal and Unless your tank was full of water I doubt it is rusted. They look like an exhaust pipe on a motorcycle with a slot cut on the end. It goes without saying that all of your gas lines outside of the tank should be replaced.

[WoodenBirdOfPrey]

The bottom half of the pickup tubes are plastic though.  The one that came out of my 87 when I replaced the tank was starting to split up the side from the plastic contracting over time.  It broke off in my hand with very little pressure, so it's not a stretch at all for the plastic part to be damaged.  If it's just starting to crack it could be still letting enough fuel through to run, but mixed with air so it won't be running at full capacity.

[milliard431]

Mine was older before plastic was widespread but I can see the plastic getting brittle

[carnuck]

I'll see if I can find the pics of the pickup tubes rotted off (due to MTBE and alcohol plus other fuel additives) I've had to change 7 myself on various rigs. Park them a long time with a partial tank of fuel and the rust starts!