Carb issue

[PensacolaJason]

On one of my carbs there is gas leaking out of the bowl vent when I pump the primer bulb. I took the carb apart and checked it and put a new kit on it. I tested that the needle is seating properly. I'm wondering if maybe I'm pumping the bulb too many times and that's what's causing it.

I held the bowl upside down and blew air into the bowl. Upside down it didn't let any air pass. With the bowl right side up, It allowed air to pass so I believe it's seating correctly.

 

[racerone]

If you won the high school wrestling championship you would be capable of overcoming the float valve.------Pump the bulb and sense that you are moving fuel till carburetor is full.-----Bulb firms up.-----Does carburetor leak when motor is running ?

 

[PensacolaJason]

I was trying to fill up all of the carbs since they were empty after just rebuilding all of them. It was frustrating to see it leaking when I did a test to make sure it was seating. I’m hoping it was just me overpowering the seat. Should I worry about messing up the seat by doing that? Should I crack open the carb again to check or will it go back to seating fine. Just want to make sure I didn’t damage it by over-pressuring the fuel system.

Ill try running the motor to see if it leaks. Would I expect to see it leak even when idling.

 

[kbait]

Drain the offending carb’s bowl and squeeze primer bulb with drain plug out until an ounce of fuel comes out, then replace drain plug and re-prime normally. May be a bit of debris holding the needle open slightly, and a quick flush could cure the issue. Good luck!

 

[PensacolaJason]

I reopened and reseated the problem carb and no more leaking. However, I took it out and it idles fine and even runs at about 3k RPM, but anymore throttle than that and it starts to sputter and lose power. Not sure what my issues is. I e tried to pump the bulb and that doesn’t seem to help at all.

 

[lindy46]

Is the float installed and adjusted properly?

 

[PensacolaJason]

Yep, I set all of the floats according to the manual.

 

[PensacolaJason]

Here is a video or two of the issue if it helps any.

https://www.youtube.com/watch?v=3Yk7rqZ78T8

https://www.youtube.com/watch?v=N2HVz0ospvs

 

[PensacolaJason]

Here is my float setting. I followed the manual and ran a straight edge along the top of the carb while inverted and the float barely touches the straight edge.

 

[racerone]

Time to do some trouble shooting !------Maybe it is NOT a carburetor problem !

 

[PensacolaJason]

Would a bad coil or power pack cause this issue? I'm wondering if it could be electrical instead of fuel. Compression is 120 psi on all cylinders.

 

[PensacolaJason]

I decided to do a spark and drop test on it to see what happens. I found that one of the cylinders was not getting any spark. I pulled the plug and found the gap to be way too large. I gaped it back to spec and now I am seeing spark on my inline tester. I then did a drop test and the motor loss power or died completely after pulling each one of the plug wires one at a time, so I think all cylinders are firing now.

My question is, would a single cylinder not getting any spark cause the issue that I am having in the videos posted above or would they just contribute to a part of it?

 

[racerone]

Power coming on off instantly like that indicates ignition problems.----Test run with cowling off.----Test run with timing light hooked to # 1 and observe spark behavior.----Repeat with other 3 cylinders.----Testing is the path to take.

 

[oldboat1]

Here is my float setting. I followed the manual and ran a straight edge along the top of the carb while inverted and the float barely touches the straight edge.

You are picturing the inverted bowl of the carb -- assume you get a float drop into the bowl when the bowl is right side up. Is there a measurement in the manual for that drop? It's possible the bowl isn't refilling properly. The carb needle valves need to be adjusted per the manual, and tweaked for best operation.

With the cowling off, as mentioned above, you may see some sparking/shorting/leaking that is causing issues. When measuring spark to test magneto strength, use an adjustable open-air tester rather than the inline type. You should see a sharp spark of about 1/2 inch. Spark plug gap setting is probably .030.

 

[PensacolaJason]

I had someone with knowledge of small 2-stroke motors take a look at it and they feel confident that the fuel delivery is not an issue and that it is likely a power pack going bad causing it to drop to 2-cylinders. I am ordering a power pack and will report back with results this weekend.