1981 g1 carb issues

[Steelworker77]

Purchased a g1 yesterday with known running issues.
Was told it was a 1984 but after finding Vin seems to be a 1981.

Will run if you dump some gas in the carb and will continue to run some but runs itself out of fuel.

Previous owner stuck a new carb on it and unhooked oil injection /went premix since new carb didn't have ports on it for it.

What I am worried about is the carb may be hooked up wrong or isn't the correct carb. I have adjusted and set the float heights but no help.

The small line with the bolt in it where does that originally go? Assuming that is the fuel inlet from the pump beside it? The hose on the other side is just hanging out in mid air. Is that correct?

Plan on contacting plowmans to order parts to refresh everything.

Top end, crank seals, intake gaskets, fuel filter, Spark plug, fuel pump, fuel lines.

Clutches seem to need some work as the primary doesn't seem to What to release all the time.

Any help is appreciated

[slonomo]

Is there fuel getting into the bowl?

Are you getting fuel from the pump?

The hose that has the bolt in it goes to the oil injector, so it's disconnected that should be ok.

The hose next to it with nothing on it, that's the vent line, it should have a short piece of hose just running to atmosphere.

The port on the other side is the fuel inlet.

I'm going off memory so.....Give that a try see what happens. Some of the aftermarket carbs are wonky. It seems the Chinese have their own way of designing carbs. I've seen China copy carbs have the fuel inlet in a different location than the factory carb.

You can blow air (not compressed) through the inlet and see if it comes out in the bowl. Tip the carb upside down while blowing air into it and the air should stop, that's basically testing the needle/seat/float operation. I usually just use a clean piece of hose in my mouth to to the test. Use gentle air pressure. You should hear the air coming out inside the bowl, then when you tip it upside down it should stop. That will ensure you have the fuel inlet.

Did the seller give you the original Mikuni? Those are much better carbs. Usually old carbs can be cleaned out and rebuilt with new parts. Those Chinese aftermarket carbs are trash. Don Plowman will have a solution for a good replacement carb, he advocates the original though.

Also what premix ratio are you using? Too much oil and/or the wrong kind of oil can gum up a carb.

[Steelworker77]

There is fuel in the bowl and I have adjusted floats. The port next to the oil injection line that is plugged off was hooked up to the fuel pump so maybe that was the problem. I will swap and give that a try. No original carb came with It. I will see if this works and if not try to locate a better one. Thanks

[AGELE55]

Originally Posted by Steelworker77

There is fuel in the bowl and I have adjusted floats. The port next to the oil injection line that is plugged off was hooked up to the fuel pump so maybe that was the problem. I will swap and give that a try. No original carb came with It. I will see if this works and if not try to locate a better one. Thanks

Here’s a couple pics from my 84 G1 during rebuild. Looks like you have your lines swapped.