Fuel/carb problem need help

tomnj

tomnj

Old fogie stogie
My 128 has a 1979 1.5 strada engine w/carb which I believe is almost identical to the X1/9 carbed 1.5. It is completely stock. I am having a fuel starvation problem that I can't figure out. First, when the car sits for more than a day or so, it can't be started without spraying starter fluid in the carb. It's as if the entire fuel system is dry. Once I spray some starter fluid in, it starts right up and runs well, good power, smooth idle. However while driving the car will cut out on me sometimes, like it's out of fuel. It sputters, then stalls. I can restart it after a few cranks and drive away, but then it cuts out again. Idling seems to help "build up" fuel and therefore help the car go longer without cutting out, but not always.

I have replaced the fuel lines, the filters and the pump (electric). I have verified the pump is working by pulling off the fuel line and watching the fuel get pumped out when the engine is started.

My gut feeling is that the float bowl is leaking or not keeping the fuel at the proper level. But can't understand why the car can run good sometimes. I can hear a trickling or gurgling noise from the carb after shutting the motor off, not sure if that is normal. The carb may need a rebuild, but the car will idle and run well sometimes and I've used carb cleaner in it. Any ideas?
 
I've had six 79's...

...that initially had that same carb. Not a great carb, by any means.
However, that aside, you may have a minute piece of dirt or spec of fuel line fragment that is floating around in the carb, every once in awhile finding its way to block a passage. Once the car is shut down or the fuel moves around, it is freeing up that passage again. A complete rebuild may be in order, but first try pulling the jets and cleaning them out individually (making sure they each go back into the same place they came from). Won't hurt to try.
 
!

Gurgling isn't good. I'm not super familiar with that carb, so somone else will probably have a more precise anwer.

Usually, gurgling is caused by vacuum being exerted on the float bowl. Maybe the vent to the float bowl is stopped up. If there is vacuum in the float bowl, air will be sucked back through the fuel jets (gurgle), and no gas will go out of them either.

Here's where I'm guessing now: Some carbs of that era had anti-dieseling valves installed to intentionally exert vacuum on the float bowl to get the car to shut off (back when gas was really low octane). If your carb has an electric wire going to it, that's probably an anti-run-on valve. If it don't work, your car don't run.

Otherwise, carb floats with pin holes can do funny things. Depending on the barometric pressure, they can suck fuel in and sink, or blow fuel out and float. As stated above, it's probably time for a good carb rebuild anyway.
 
Thanks guys, some good information there. I'll have to check the jets and vacuum lines. I will consider a rebuild, but that will cost me some $$ since I would leave that to a pro. Maybe a new carb is a better option since its a 1973 car without half the pollution controls the 79 came with. What carb type would be a good choice as a replacement if I go that route?
 
Tom... Eddie has some good points...

BUTT...

BB4RE and I will GUARAN-DAMN-TEE ya that its in the carb.

Megabucks are NOT required and neither is too much skill.

Exploded drawings are available on this site and all ya need is 20 bucks worth of carb cleaner in a bucket. If you are careful, you can even reuse the gaskets and internal parts. A rebuild kit is NOT required but NOT expensive either. I've even made my own gaskets in a pinch.

Once cleaned after a 30 minute soak, rinse in paint thinner (or carefully with gas) and then BLOW out the passages with compressed air.

Same with all the tubes and rods and make sure they are reinstalled where they came out!

I messed with several of these and the carb "boil-out" is the only way to rid yourself of this problem.

If this still sounds like too much for you... get with Mad Matt or BB4RE and see if they have rebuilts for ya...

Hope this helps, actually, I hope I've inspired you to give it a try!
 
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