HD 25 Carb percolting

[fisherman6]

Very nice work. Great find. Thank you for sharing thus info. I have a couple of these motors I haven’t worked on yet. This will definitely be something I’ll remember to check for.
-Ben

OldJohnnyRude on YouTube

[shane-r13]

quote Chacha53:

Shane. How could you hear gas boiling in the carb while running? My engine makes so much noise as to drown out any other sound. If the gas is boiling you will see it bubbling out of the top of the carb around the float needle sticking through the top. Do you see it doing that? If you have a mist of water coming out the exhaust holes on the midsection then I think your cooling system is working. If you’re engine runs for awhile then stops, I would bet it’s a carb issue.

I cant hear it while running. As you said these motors make a racket.
When it dies and i put my ear to the carb you can hear it bubbling and see gas seeping out of the float need as you stated. I took my carb off and check my gasket to make sure I wasn’t having the same issue as you. Sadly My gasket was fine. I tore the bottom end off it ran wires and and air and engine cleaners through all tubes for cooling etc. And it actually ran for longer than i have ever ran it, then it heated up again. I don’t know I’m lost, its going on the back burner for now i guess. Other motors have taken priority.

Congratulations on persevering and finding a solution to your though!

Shane

[chacha53]

Thank you! I think my problem with the gasket is probably a rare occurrence.
Did you remove the drain screw at the base of the head while the engine is running to observe the flow? The flow on mine is not strong, more like a garden hose with the water turned on very low and no sprayer attached to the nozzle. But if you are seeing water come out of the exhaust ports on the midsection, then I think you are getting enough water through the powerhead. Maybe on your next attempt you should try altering the carburetor passage as outlined in the diagram earlier in this post. I wish you luck with it.

[shane-r13]

quote Chacha53:

Thank you! I think my problem with the gasket is probably a rare occurrence.
Did you remove the drain screw at the base of the head while the engine is running to observe the flow? The flow on mine is not strong, more like a garden hose with the water turned on very low and no sprayer attached to the nozzle. But if you are seeing water come out of the exhaust ports on the midsection, then I think you are getting enough water through the powerhead. Maybe on your next attempt you should try altering the carburetor passage as outlined in the diagram earlier in this post. I wish you luck with it.

Yup of course my carb gasket was good not like yours. I have already altered the carb body with no real tangible results from it. I have water coming out of the drain screw on the head but low and slow like you described. if i put my hand by the exhaust ports there is a mist of water and my hand becomes wet. Generally within a minute it seems to overheat and die. Last time i tore it apart and reassembled it ran for maybe 5mins before it died and wouldn’t start until cooled off. Probably at this point going to stop putting money into it and buy another one since they are not exactly rare and just use this guy for parts.

Shane

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