15 replies to this topic

[Bobinyelm]

After getting my Honda 2000ui back together after extracting the runaway spark plug I spoke about in another post recently, my Honda would only run with the choke partially on, alerting me that I probably had some carburetor problems, possibly from old fuel residue, since I hadn't used the generator for many months.

For those who have not yet had occasion to clean their carburetor, I offer the following procedure. It is harder to describe the work than actually do it, and hopefully I can dispel any fears anyone may have of digging into the little bugger.



Cleaning the Carburetor
(see below how to remove the carburetor if uncertain)

Upon disassembling the carburetor (accomplished by removing the 10mm headed bolt retaining the carburetor's float bowl), it was obvious that considerable green algae had grown on the small amount of gasoline residue in the bowl over the past several months that was clogging the very small carburetor passages.

Using spray car cleaner, and a lint-free rag, I cleaned the green gunk from the bowl and down in the drain cavity (remove the small brass bowl drain screw to get down there to clean all the algae out).

Remove the float and needle valve by sliding the hinge pin out and lifting the float w/ needle attached and carefully and lay it aside, cleaning them with both gently a shot of cleaner and a gentle wipe w/ the rag.

Using a small slotted screw driver the width of which is almost the inside diameter of the threaded center post of the carburetor (from which you removed the bolt to remove the bowl) "feel" the screwdriver as in engages the slot in the main carburetor jet at the bottom of the post and remove the jet (counter clockwise).

Hold the jet up to the light to see if the hole through the jet) is fully open.

Mine was partially clogged, though I could still see some light through the drilled hole. I used a length of small diameter wire to clear the hole as well as the recesses of the jet transitioning to the hole. These recesses held a decent amount of algae that had to be "picked out" with the wire. I used brass plated 0.021" diameter "hobby" wire, and was careful not to enlarge the drilled hole in the relatively soft brass jet.

Note: If you intend to operate your Honda at high altitude (above 5000ft), the brass jet I refer to directly above is the item you will want to swap out with the stock jet that came w/ your Honda, using one obtained from Honda for high altitude.

Spray carb cleaner through all of the passages in the carburetor (shoot it into the idle jet hole and transition holes visible looking into the carburetor's air passageway by the throttle plate, or "butterfly").

If you have an air source, you can blow some air through the passages in the carburetor to ensure they are open.

Assembly is the reverse of the above steps, making sure that you install the bowl with the drain oriented on the choke side of the carburetor.

Carburetor Removal

1) Remove the two silver 8mm headed nuts from directly at the end of the carburetor (located in the air cleaner extension.

2) Then after removing the large slotted screw in that air cleaner cover, remove the lower mesh insert to reveal a silver 8mm headed bolt that you need to remove.

3) Carefully remove the air cleaner (and the large attached rubber hose) that is inserted into the crankcase and put it aside (with the black gasket that lives between the air cleaner and the carburetor).

4) Slide the carb off the two long studs, removing the clear plastic tubing and the black fuel supply hose. That will leave the carb attached by the throttle motor under the white nylon cap. Leave the green gasket on the two studs so it won't get lost.

5) Depress the 3 clips retaining the cap, removing it, then unplug the small electrical connector, and separate the cable/plug from the motor, allowing you to remove the carb assembly from the generator for cleaning (or just replacement as described above).

From now on, I will resolve to drain the fuel tank and run the generator dry each season to preclude having to do this cleaning procedure every time. If you're not going to use the generator for perhaps only a month or two, simply draining the carburetor is probably sufficient. To do that, just remove the side cover, and unscrew the bowl drain screw a few turns (CCW). No need to remove it completely-the fuel will drain via the clear tubing through a hole in the bottom of the generator case.

Edited by Bobinyelm, 04 April 2009 - 04:09 PM.

[Paul from NWOnt]

I always admire the tenacity of someone willing to take the time to do it right.  Kudos!

Personally, I would have dumped a "glug" (technical measurement term) of either fuel injector cleaner, or seafoam fuel system conditioner into the tank, and let it run dry.  While I admit it ReAlLy has it's shortcomings, I've had great success on both my motorcycle, and snowmobile using this method.  I imagine my system wouldn't help with a well fouled carb, but for minor issues, it eliminates the need for tools, and shouldn't do any damage if it doesn't work.

[Bobinyelm]

I always admire the tenacity of someone willing to take the time to do it right.  Kudos!

Personally, I would have dumped a "glug" (technical measurement term) of either fuel injector cleaner, or seafoam fuel system conditioner into the tank, and let it run dry.  While I admit it ReAlLy has it's shortcomings, I've had great success on both my motorcycle, and snowmobile using this method.  I imagine my system wouldn't help with a well fouled carb, but for minor issues, it eliminates the need for tools, and shouldn't do any damage if it doesn't work.

Given the amount of dried-hard algae I found in there, I am glad I didn't do that, actually, though I had seriously considered it.
Most fuel system cleaners will remove varnish, but even with spray carb cleaner applied full-strength and allowed to sit (stronger than fuel additive types), I had to physically scrub and pick to get the crap loose.

I've seen aglae form in diesel fuel, but never in gasoline. Perhaps it likes the corn ethanol in most gasolines these days.

Bob

Edited by Bobinyelm, 04 April 2009 - 04:15 PM.

[Dan & Jan]

After sitting in storage for several months my Honda EU2000i started but had a lope on econo mode.  I did pretty much the same thing as you described, took the carb off but only gave the carb bowl a good cleaning and a good dose of carb cleaner in a spray can down into the main jet followed by a blast of compressed air.  It did the trick...runs perfect now.  All in all, pretty simple, about 10 or 15minutes job.
D & J
17' Casita SD

[Fireballsocal]

To add onto Bobs post, I believe his pilot jet was blocked. The choke/fast idle function of todays carburators bypass the pilot jet which is why it ran with the choke partially on. The pilot jet is also the smallest oriface so it naturally gets plugged first. Sea Foam can sometimes clear these jets out but there is no telling what has dried up in your float bowl, best to clean it the right way. It really isn;t that difficult. A hint is to disassemble on a large rag so any parts that drop can be spotted quickly. Also the float bowl screws like to strip out. If you don't have an impact driver, then inserting your screwdriver into the screw and tapping the screwdriver firmly with a mallet or hammer several times will break the corrosion that binds the screw.

[Don in OKC]

To add onto Bobs post, I believe his pilot jet was blocked.

It's usually the main jet orifice that gets clogged.

This is the level at which the carb float bowl has gasoline that evaporates overtime and leaves 'varnish' which plugs things up.

This is why it runs with the choke 'on', and dies with the choke 'off'.

It's best to use a round wooden toothpick to poke into the main jet rather than wire, but Bob makes the point of being careful which also takes care of it.

Here's a photo of the carburetor off and the main jet out. It's possible to fix it without removing the carb once you've done it.

===

It takes a screwdriver that's 'not too small, not to big, but just right' to get the main jet out without buggering it up.

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Edited by Don in OKC, 05 April 2009 - 09:13 AM.

[Fireballsocal]

I apologize in advance for disagreeing but, the main jet is almost never plugged. The choke bypasses the pilot jet, not the main jet. The  pilot jet is small compared to the main and gets plugged sooner. While the main jet can get a coating of dried gasoline or varnish, it is almost never enough to plug it completely. Then, when the generator is ran, the gasoline flowing through the main will remove the varnish with time.

[Don in OKC]

I apologize in advance for disagreeing but, the main jet is almost never plugged. The choke bypasses the pilot jet, not the main jet. The  pilot jet is small compared to the main and gets plugged sooner. While the main jet can get a coating of dried gasoline or varnish, it is almost never enough to plug it completely. Then, when the generator is ran, the gasoline flowing through the main will remove the varnish with time.

Hello Fireballsocal. Yes we disagree.

My experience is with single cylinder motorcycles of the 70s and 80s. I can't count the number of times I've rolled out a motorcycle that's set neglected thru the winter and wouldn't start/run.  Blown out the main jet and had it fix the problem. I'd argue the theory also, but there's no need...... I'll be sticking to my story.

Respectfully, Don in OKC

[Fireballsocal]

Lol, I guess we agree on something.   It only matters that the problem gets resolved and as long as it does, then everything else is gravy. This is my 85. I have 7 singles, both four and two stroke, 2, 3, and 4 wheels and I most definitely have purchased about half of them with plugged carbs. It's a great way to pick up a cheap bike if they have sat.

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[Don in Ut]

I also forgot to add some fuel stabilizer to the gasoline tank on my Honda generator.  When I started mine it did the same thing - it would lope (surge) and would only run smoothly with the choke on part way.  Most of my carburetor experience has been with cars I owned before fuel injection.  I disassembled and cleaned several carbs before I learned that nine out of ten times the problem could be resolved with a can of carb cleaner in the tank.  I didn't see any reason why I couldn't do the same on the Honda but I called my favorite small engine expert anyway.  He said it wouldn't hurt anything and recommended a product called Sea Foam.  I put a little in the tank, cranked it over and let it run for about five minutes.  Suddenly it began to run like new.  I'm going to do the same thing with my lawn mower.  It used to always start with one or two pulls.  Now it takes three or four.  Can't hurt.

Don in UT

[CaptGeorge]

I always use premium gasoline in small engines including my Honda generator.  The premium gas is very stable and requires no additives.  Lawnmowers, generator, edger, etc. always start on second pull.

I did have a problem loaning out my Honda generator to daughter during Hurricane IKE power outage.  She mis-interpreted the choke position and ran it on half-choke just to get it to run.  This fouled the plug of course.  After listening to her, I realize the choke setting can be confusing.

The attached pic shows the RUN position - even though the lever is under the CHOKE icon.  Her logic was CHOKE meant CHOKE and ARROW meant RUN. Hummmm.... I wonder how many have made that mistake.

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Edited by CaptGeorge, 07 April 2009 - 10:53 AM.

[Bobinyelm]

In my case it was the MAIN jet (the one shown in Don's fingers in his excellent illustration) that was almost completely clogged.

Most cleaners WILL remove varnish, but not so sure about green algae (since the algae is water soluable, and probably not soluable in petroleum based cleaners like SeaFoam, Gunk, etc.).

In my case, even with straight carb and choke cleaner (strong enough to remove cured paint, but after soaking for 15 minutes wouldn't touch the algae), the only way I could remove the algae was by mechanical means (scrubbing and picking at inside the recesses and orfice of the main jet to remove it).

The smaller pilot/idle passageways appeared perfectly clean (probably because they were largely above the fuel level in the bowl). Only the bottom 1/2" of the bowl and center post into which the main jet screws had algae. The bottom of the white plastic float also had a heavy coating of algae on it, BTW.

The fuel in the bowl smelled slightly stale (varnishy smell), but there was NO varnish (amber/brown deposits) in the carb whatsoever. No water appeared to be present (since all drained fuel evaporated promptly).

Bob

Edited by Bobinyelm, 07 April 2009 - 04:33 PM.

[Don in OKC]

Captgeorge:

Yup, as good as the little EU2000 is, the graphics aren't user friendly. Not only the choke, the gas cap vent is puzzling. I had some vinyl letters (from Hobby Lobby) left over from another project that helped.

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[Xeno]

Do you guys drain the bowl if your not using it for a few days?

[Fireballsocal]

A few weeks to a month and your fine without draining the float bowl. I tried to run mine once a month to excersise it. After a couple of months is when you start seeing fuel system issues on these small engines. That is just about standard for most small engines.