Gunk in the carb

Stinky

Stinky

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We just got back from Buttercup...it was a pretty good Spring-Break trip.  It rained on us.  Afterwards, the sand was like drving on a wet beach.  The next day, there were no tracks/ruts.

I took 3 ATVs.  2 of em had carb issues (a Honda Recon and a Yamaha Timberwolf...(both half tractor, out of place in the dunes).  We took both of em apart 2x each.  The one still has float issues.  Not sure if it needs a new needle, or if there is crap in there.  It had gunk in the bowl and jets both times we took it apart.  The other....we took it apart and it ran fine.  An hour later, we did it again.   This time, it had gunk in the bowl...a lot.  It looked like dirt, and plant matter.  We took the tank off and cleaned it, but didn't really get anything out...but I suppose we coulda got enough to prevent problems.  It also had a bunk of gunk around the petcock.

Sooooo, here is the Q.  What sort of steps should I take to alleviate these issues?  Should I leave gas in the tank?  The problem w/this is that I could see easily leaving 1/8" of gas in the tank, cuz you can't get it all out, and then having it dry up and forming junk/gunk that later gives you issue.  

Should I drain the bowl?  I always, or almost always run them dry.

How much difference does a filter make?  I just added one to both machines.

Another side question, I have 2 Honda Recons.  They both have an accelerator pump.  All those hoses are a pain to work around.  Can they be deleted?  I'm thinking that simpler is best.   

 
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You should also have a screen in the petcock assembly that could be hiding gunk. If you are getting junk plugging the pilot jet, it has to be coming from somewhere so clean the tank, petcock, and carburetor really well. A 1 gallon pail of berrymans carb cleaner works great for petcock and carb cleaning. Just make sure you have new gaskets and o rings on hand before disassembly. A Q tip works great for cleaning the needle seat but if the seat is worn, replace it and the viton tipped needle with OEM Honda parts. 

  On the accelerator pump question: You bought a honda/yamaha for a reason. I would suggest trusting their engineers and not removing bits and pieces. They are supposed to be there. 

  If you store the bikes longer than 6 months, draining the tank and carburetor and using fogging oil in the tank/petcock, carb, and cylinder is the best way I know to store. It's a little time consuming but you are guaranteed to run after adding fuel. Less than 6 month, you can either use stabil fuel stabilizer or run the bikes once a month for 20 minutes. I find a big bottle of stabil is a great investment as I always forget to run the bikes.  

 
Best thing you can do. Quit using california gas. The ethanol corrodes all the brass components in your carb (they turn a weird shade of green). Even after just a week or two.  Turning the gas off and letting it dry out actually makes it worse.

run only ethanol free fuel, avgas, or race gas. no more rebuilding cRbs during the season. And if properly stored and prepped, good for years

 
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Furball offered some good advice.

For me, I would drain the gas, drain the carb and then spray WD-40 in the carb and it worked for me.  BUT...I also cleaned the carb and replaced the pilot jet before every season.  They're $5 and you'll drive yourself crazy if you have the least little clog in your pilot jet.


You can use Seafoam.  If you do, use only as much as you need and make sure you run it all out.  If you leave Seafoam in your fuel system, you will be sorry and end up replacing all rings, hoses, and everything plastic or rubber.

 
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In line fuel filer - always...close petcock and let bike run until it dies when you won't ride it for a few weeks...and if you have a china carb, get rid of it and get OEM
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If you can get your hands on Avgas that's the way to go, its not much more $ than 91 and since I went that route I haven't had carb issues, even on the pit bikes  my kids only ride a couple times a year, its pretty amazing they can sit in a hot AZ shed for 10 months and start on 2nd or third kick! gotta love honda 50's!  

if that's not an option, install a in-line filter between the carb and petcock like you have done, they do help stopping crap getting to the carb as long as they are not the cheap amazon junk ones. I get mine from Napa, ill try to find the part number.  also when you store it drain the bowl completely and either totally drain the fuel tank if its a plastic, or for steel tanks leave it 100% full to prevent more rust. the gas left in the tank will be no good after a couple months so when season comes back around it will need replaced.

when running regular pump gas if its stored too long you'll always have some issues. but a drained bowl and filter should solve some of them.   

 
I generally only run real (Non-Ethanol) gas.  Right now, they have AZ pump gas in them.  I only took about 4 gas cans w/me this trip.  The last day, we had to re-fill in Yuma.  I have, at least, 3 stations in my town that sell real gas.

I've been having pretty good...until this last trip, draining out all of the gas, tank and carb.  I think that I'll continue doing that.

 
I normally run the Chevron 91 that I put into my buggy, in my Genny (Generac).  at the beginning of every off season I put some Stabil Fuel stabilizer in each and run them for a bit.  the genny I shut off the petcock and run the carb dry, then put it back into the trailer until fall.  been doing that since 1999 when I bought it.  The buggy I try to start every few months, just to circulate fluids.  maybe take it for a spin around the block to wake up the neighbors.  might not help with your situation, but it a data point.

 
You got something dirty (literally) in your gas tanks.  I've never had carb issues in my Banshees for 20+ years.   That's with CA gas and sitting for long periods sometimes.

My 70s get gummed up occasionally with old gas but nothing like dirt or debris.  Jets are tiny holes.

 
I had a similar issue a few years ago. Fuel tank was clean, gas was good. Turned out that the filter screen in the petcock was slowly deteriorating causing all of my problems. New petcock and no problems since. FWIW, I drain the carb after every trip and use pump gas with no issues. When the bikes are stored in the off season they have fuel in the tank. Drain and  put fresh fuel in at the beginning of the season, never an issue. I also replaced the stock float bowl drain plug with a sump style as a little extra insurance if there does happen to be any debris in the FB. 

 
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