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Small engine/carburetor experts...

Jason280

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Mar 4, 2012
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I picked up a couple '06 or '07 Honda 400 Rancher AT 4-wheelers, and they have been sitting for a while and won't crank. I've pulled the bowl off one of the carbs, and have been trying to get the jets cleaned out. I've gotten to what I believe are pick-up tubes, and one seems to be completely blocked off (but I am not 100% sure). Here's the tube in question:






...and here's the carb:





Now, in trying to get the tube cleaned, I cannot get a wire tip cleaner all the way through. Its blocked in the middle, but I am not sure if that is by design or not. I can fit a 1/16" drill bit in, but not sure if I should try to drill all the way through. Should it be open from one end to the other?
 
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galute

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Jun 28, 2010
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Bald Knob AR
Yes there is a hole all the way thru. Not sure of the size but I doubt it's a 1/16. If you have some lacquer paint thinner let it soak in that a while. Best stuff I ever used to clean a carb. Just make sure not to get it on any rubber or plastic.
 

PassnThru

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Bowling Green KY
Not an expert but been there before. Before poking you should be soaking :lol_hitti
Really - soak everything in carb cleaner / sea foam / your weapon of choice. The hole in that is very small - it's easy to miss.
I'm a little concerned that it isn't doing anything though. Did the float bowl have fuel in it? My biggest problem with carbs seems to be that they will start and idle but not take gas.
 

redmondjp

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Redmond, WA
Not being intimately familiar with that tube, I can't say for sure - what I would do it to use a strong flashlight to sight down one side to see if there is an opening or not. I would certainly not recommend drilling it out. If it appears that there is an orifice there, I would use very small wire to try to clean it out.

I like to use the tiny steel wire that is inside those plastic bag ties for cleaning out small carb orifices, as it is a small enough diameter to get through even the smallest holes.

Here's another idea - you say that you got two ATVs - by any chance, do they have the same carb on both of them? You may be able to look at the same part on the other carb to see what it is like for comparison.
 

Lx460

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Central Florida, USA
That is the pilot jet or "slow jet". Yes the opening goes all the way through. This operates from idle to about 25% throttle. If the bike won't idle, that's usually the problem. The openings are so minuscule that a rebuild kit for $25 would be a good idea. Poking around with a wire, etc. can distort the soft brass and make it run weird. It also looks like the bike sat with ethanol gas in it for a while as evidenced by the tinted green plastic floats.
 

Streetbu

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Jan 7, 2014
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Central NY
Don't drill it! That is a specific size. Clean it or replace it only. I often use the wire from a bread bag twist tie...
 

OccupantRJ

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Eastern North Carolina
The number stamped on the side of the jet assembly is usually the size of the hole in millimeters. If it is 25, it is .25 mm. This jet has been stopped up on the majority of Honda bikes I have dealt with over the years if the bikes have been sitting up for long.
 
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robin1731

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Dec 25, 2007
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Decatur, Indiana
Like most have said, poking is not a good thing. Soak it and use compressed air to clear it. Looks like number 45 on the side of it. Even when the pilot jets are clean you can see very little light through them. Make sure the holes on the sides are clear too.

And make sure you pull the main jet and tube out to check those. That is the larger one that sticks up further.
 

Showkey

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What they said In the last four posts...........But at the bare minimum the all the jets, the air screw, the float needle and seat, the diaphragm on top of the slide and the assorted passage ways need to cleaned with spray carb cleaner and compressed air. Often there is a filter screen on the top of the float seat. The float needle is rubber tipped must be clean and free from imperfections.

Hold that pilot jet to a strong light if can not see light your not done.

Often when they sit a complete disassembly and soak in carb cleaner is needed. There rubber part, diaphragms and orings that do not like super strong solvents that why a complete disassembly is needed. Often a specialized soak carb cleaner in needed to loosen the dried varnish and gummed up mess. Old school nasty carb cleaner was called hydro seal ......has an unforgettable smell.

The fuel tank also must be addressed or your carb cleaning will not last and those jets will be plugged with **** from the tank. Bad fuel and rust in the tank usually goes with that carb issue.

This needed carb work is not the reason it does not turn over or crank. If the engine is stuck or frozen from sitting that is a much bigger issue.

This is not a Honda problem but an industry wide problem with ethanol fuel that sits untreated. Small engine guys put their kids through college or buy a bigger boat on the work that stale bad fuel creates.
 
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jsantoro

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Mar 14, 2007
Messages
15
Ultrasonic cleaners do a good job on carb parts. This slow jet was used on tons of Keihin carbs from the 80's on. As Showkey stated it's caused by Ethanol and the **** gas in general. The rest of the carb is probably gummed up as well.
 

Lx460

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I have to disagree somewhat. Do not use any kind of cleaner on the rubber diaphragm of the slide. The rubber is delicate and gets compromised by carb cleaner. Never put any rubber or plastic parts in carb cleaner that you want to survive. I usually just wipe them with a hot soapy cloth and check for holes or damage. They are not exposed to gasoline, and as such don't get that dirty.
 

Showkey

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I have to disagree somewhat. Do not use any kind of cleaner on the rubber diaphragm of the slide. The rubber is delicate and gets compromised by carb cleaner. Never put any rubber or plastic parts in carb cleaner that you want to survive. I usually just wipe them with a hot soapy cloth and check for holes or damage. They are not exposed to gasoline, and as such don't get that dirty.

Agree........when I said complete disassembly is done when doing a complete cleaning is to get and keep the sensitive parts like diaphragms, orings, switches, electric solenoids away from the nasty solvents.:beer:
 

scooterboy

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Nov 12, 2013
Messages
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Location
Ft Wayne IN
I work on Scooters (Mopeds) most every day and they have a carburetor very similar to yours. That is the idle jet or some call it the pilot jet. It has a very small hole in it. I use a #80 drill bit to clean the jet. This is smaller than a 1/64" drill bit. I just did a carb tonight and the same thing a plugged idle jet. If you can't clean it you can order a new idle jet. You will have to completely take the carb apart to clean it. I use carb cleaner and compressed air to clean all passage ways. I just noticed the 45 on your jet so use a #77 drill bit (0.4572 mm). You could also order a new carburetor on Ebay.

Good Luck!
 
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