Yamaha G1 starts on idle but won't rev up and engage 2 drive

[Spicyunicorn]

Cgtech correct me if I'm wrong but this is my theory.... This is what i first thought of crank seals are worn and when starter is engaged it is sucking in air past the crank seals rendering the "pulse" but as it slows down after the starter is disengaged the seals actually "seal" enough to create a small pulse to push a little fuel as the motor is at a slowerer rpm than starter spins if that makes sense?

[cgtech]

Well, might check compression. Have the seals ever been done?

[Green Planet]

Let me start by saying THANK YOU, to all the members who posted suggestions. I could not have done it without your help.

To recap, my G1 ran out of gas , as I do not have a fuel gauge. It was running fine and the just quit. The gas level is the first thing I checked, and I added fuel and tried to start her. Correct me if I'm wrong but I believe that I got air in the fuel pump and it lost it's prime. After checking the things that cgtech told me to check, I was able to identify a lack of fuel to be the problem, then spicyunicorn told me how to check the fuel pump. When I checked the fuel pump discharge line that feeds the carb... no fuel came out, but when I let of the pedal some gas sputtered out. I did this twice and both times no fuel when pedal depressed, but when released some fuel came out like 2 to 3 pulses. Last night CGTECH wrote back to me saying that that was not probable, so today I was going to video post what I was seeing, prior to taking the video, I wanted to verify I was still getting the same results as yesterday. Well to my joy and happiness I was not.
I reconnected the fuel supply to the carb and went to fire her up by way of the pedal. And no start....hmmmm. Well I was looking at the choke cable and it looked a little loose so, I manually engaged the choke bypassing the dash choke cable AND Vroooooom she started. A little wd40 on the choke cable brought back the proper tension. I am back up and running
Thanks again for your help and support

[ewbldavis]

Originally Posted by cgtech

Lets clarify... Just because the engine on a G1 spins on the starter, and tries to turn the wheels does not mean it "idles". Golf cart engines do not "idle", they stop running when you let off the gas. Unless you can hear distinctive "pop-pop-pop" sounds from the exhaust, its not running at all. First, check for throttle movement by pressing gas pedal with key off to see if throttle at carb moves with pedal press. Second check spark while cranking engine (with a spark tester, or your spark plug grounded to the engine). If the spark test & throttle test is passed, spray a shot of ether or carb cleaner down the carb air inlet (only a brief test, as it provides no lubrication for the engine provided with the regular fuel mix). If these tests dont provide signs of life, do a compression test, anything over 100psi should run (maybe not a lot of power at 100psi, but does run, seen engines with as little as 85psi "run").

Actually, if you disconnect black wire with white stripe on a G1, it will, in fact, idle nicely.

[cgtech]

Originally Posted by ewbldavis

Actually, if you disconnect black wire with white stripe on a G1, it will, in fact, idle nicely.

Not idling if its not "pop-pop-poping", just because the engine is cranking doesnt mean its "idling". If you disable the pedal switch AND adust the butterfly, it can be set to idle. In general, I am talking about "as designed by yamaha", most people keep the "starts when pedal is pressed" configuration. And when diagnosing issues i assume stock style starting, unless stated that "i set it up to idle".