[Larryplbg]

Unfortunately I let gas go bad in this machine and trying to get it running now. Ran great before my neglect. Pulled carb and cleaned thoroughly. It will now idle fine but will not rev up unless I mostly block off the air intake. Diaphram appears completely intact. I put fuel air mixture screw back to its setting. Fuel flow to carburetor is good and I put a in-line fuel filter in case junk in tank and pulled carb and completely cleaned everything again, but same result. It will only rev up if I block the air intake
Please and thank you

 

[fishfiles]

welcome to the forums

What was your method of cleaning the carb? did you totally disassemble it and soak it in a gallon can of carb cleaner then blow out every passage , tube and jets with compressed air ----a spray can of carb cleaner doesn't work on carbs that are really dirty

 

[Goober]

Welcome Larry
Your carb is still not clean and most likely your starter (choke) valve is worn. Your carb is due for a rebuild.
Please read this sticky https://www.hondaatvforums.net/forums/repair-maintenance/11134-how-clean-carb.html

I have a 98 TRX300FW at work and it’s always been reliable. But last fall I could not get it run–took the carb off and found seds in the bowl, primer seal perished, seals cracked–even the starter valve seal was flat. Couldn’t get it back together because the bowl seal was bad. I don’t perform maintenance on work quads so i took carb to local Honda shop; cost $275 for rebuild with new starter valve, primer bulb. Set the pilot 2 turns out was perfect.

Otherwise i buy a Shindy rebuild kit and OEM starter valve, primer bulb. These pieces not cheap but worth it
Use a plastic coffee can and a little berryman chemtool. Use Deep Creep to soak those screws and put it in the freezer overnight to allow it to work in. Use a plumbers acid brush to bathe the outside of the carb first–and don’t reuse that batch of solvent unless you coffee filter it. A lot of members soak their carbs but i only soak the body in new solvent–I don’t want big chunks from dirty solvent getting into tiny passages.
https://www.hondaatvforums.net/forums/honda-fourtrax/119242-trx300-carb-rebuild.html

 

[Larryplbg]

Thank you. I will do the disassemble and soak method. I didn’t realize that carb cleaner had another besides a spray can.
I learned something new so I’m not dead yet?

 

[Larryplbg]

Thank you for your advice. I’ll do the soak method now. How long a soak does it take? And then proceed from there

 

[Goober]

Only metal; Don’t soak any rubber parts catb cleaner will melt them

Members esp Shadetree did a greAt job on that sticky

Overnight is good to loosen those remnants of bowl seal.

I use bamboo handled cotton swabs; break off the handles and use them as scrapers to get those little bits of rubber out of the bowl gasket channel. Tooth picks are OK.

I generally avoid using metal because it scratches but a brass brush or other gun cleaning brush is good

I also use small dental brushes and pipe cleaners to clean the jet passages—as far as i can go anyway

 

[Goober]

Keep in mind that primer channel can carry tiny bits of debris into the carb body. That primer channel terminates with a brass tube in the carb throat. Spray nozzle.If you get debris in the channel it could eventually block the primer spray nozzle

 

[Goober]

Berryman Chemtool and other fuel system cleaners are great. Keep in mind it contains acetone methylethylketone methanol etc. it will dissolve the fatty tissue in your skin too so always wear gloves. I use nitrile gloves and find i have to change the often. Work in a well ventilated space and don’t breathe the vapors—your brain cells are fatty tissues too. I have a cheapie organic vapor respirator i try to remember to use lol.

I also use new solvent to clean the bowl and I’m very careful not to brush used solvent into the primer channel. Use those little cleaning tools i talked about to get in the drain and primer channels.

When i get the carb clean I always attach the new primer, pour alcohol in the bowl, open the butterfly and vacuum piston—squirt alcohol from the primer to make sure the spray head works!

The primer is kinda useless; several members here remove the little pump lever and seal the hole with hondabond