Honda Carb Problem - HRB216

Truthseeker · Sep 21, 2014

Please Help my Honda Mower is driving me crazy! Here is the puzzle.

Bought my HRB216HXA in October 2001 and it ran well until the last year. Started having the engine run rough and die, plus frequent gas leaking from the carb if the fuel valve was not closed. I cleaned all of the fuel system from the cap down, checked the tank & lines for debris, added fresh filtered fuel, changed the spark plug and removed the carb several times for cleaning, but the problems persisted. Replaced with a new carb (HON16100-Z0L-023), which immediately leaked without the fuel valve closed. Thinking I got a bad float or needle valve in the new carb, I exchanged for another new carb. This second new carb is not as prone to leaking, although it does regularly, and the run problems are still there. While mowing, the engine will start to bog down and will die, but if I shake the mower a little hoping to move the float/fuel valve it will try to resume normal rpm. It may run well for a while after warming up, or it may spit, shudder, and die time after time. When it leaks fuel, the mower will not run until it has had time to dry the flooded carb.

All I know that will cause the flooding/leaking is the float and needle valve. Given that the original and two new carbs have leaked, I either have really bad luck, Honda is selling defective carbs, or another problem. I do not know much about the governor system, but I doubt it would cause a fuel leak. Can any of you real mechanics help before I trash what has been a good mower?

robert@honda · Sep 22, 2014

Truthseeker said:
Please Help my Honda Mower is driving me crazy! Here is the puzzle.

Bought my HRB216HXA in October 2001 and it ran well until the last year. Started having the engine run rough and die, plus frequent gas leaking from the carb if the fuel valve was not closed. I cleaned all of the fuel system from the cap down, checked the tank & lines for debris, added fresh filtered fuel, changed the spark plug and removed the carb several times for cleaning, but the problems persisted. Replaced with a new carb (HON16100-Z0L-023), which immediately leaked without the fuel valve closed. Thinking I got a bad float or needle valve in the new carb, I exchanged for another new carb. This second new carb is not as prone to leaking, although it does regularly, and the run problems are still there. While mowing, the engine will start to bog down and will die, but if I shake the mower a little hoping to move the float/fuel valve it will try to resume normal rpm. It may run well for a while after warming up, or it may spit, shudder, and die time after time. When it leaks fuel, the mower will not run until it has had time to dry the flooded carb.

All I know that will cause the flooding/leaking is the float and needle valve. Given that the original and two new carbs have leaked, I either have really bad luck, Honda is selling defective carbs, or another problem. I do not know much about the governor system, but I doubt it would cause a fuel leak. Can any of you real mechanics help before I trash what has been a good mower?

So it only leaks when the fuel valve is open, correct? That would first indicate the source of the leak is after the fuel valve. There is a short length of fuel line between the fuel valve and inlet fitting on the carburetor. I'd inspect and likely replace that line first, and be sure BOTH ends of the line are secured with clamps/clips.

Does the fuel leak when the engine is off, or only when the engine is running?

You are correct about the float/needle controlling fuel flow, and it is normally a very reliable system. I highly doubt you got two new carbs both with defects. The governor regulates the throttle plate (maximum ending speed) and otherwise does not have any fuel-flow control.

Is the fuel leaking from the same exact location? How about some pics?

Truthseeker · Sep 22, 2014

robert@honda said:
So it only leaks when the fuel valve is open, correct? That would first indicate the source of the leak is after the fuel valve. There is a short length of fuel line between the fuel valve and inlet fitting on the carburetor. I'd inspect and likely replace that line first, and be sure BOTH ends of the line are secured with clamps/clips.

Does the fuel leak when the engine is off, or only when the engine is running?

You are correct about the float/needle controlling fuel flow, and it is normally a very reliable system. I highly doubt you got two new carbs both with defects. The governor regulates the throttle plate (maximum ending speed) and otherwise does not have any fuel-flow control.

Is the fuel leaking from the same exact location? How about some pics?

Thanks for the reply.

Yes, the leak is after the fuel valve, and only when it is open. The lines and valve have been thoroughly inspected and cleaned. Pics would only show fuel leaking from the carb and the air filter being wet. The leak is only evident once the engine has stopped - BUT, when the engine is running rough, a little shake of the engine affects the performance and RPM- as would be expected if the float/needle valve function is impaired. The leak has been noticed after the engine has died on its own, and after I have turned it off, but forgot to close the fuel valve. While operating, I have been repeatedly forced to pause and gently shake the engine via the handle to keep the motor sputtering until it regains an attempt to run. Sometimes it keeps trying to die, other times it becomes smooth enough to mow a little before sputtering again. The only thing that comes to mind is the needle valve is not controlling fuel flow, but after two new carbs, I am out of logical solutions.

robert@honda · Sep 23, 2014

Truthseeker said:
The only thing that comes to mind is the needle valve is not controlling fuel flow, but after two new carbs, I am out of logical solutions.

After two carbs, I'd be hard-pressed to say the problem was still within the carburetor itself. Just does not make sense that two new carbs would have defective floats and / or needle valves. The problem must lie somewhere else.

I'd double-check and confirm all gaskets, spacers, insulators are properly installed. It's possible to fit them inverted or backwards. Make sure are spring, rods, and correct holes are used on each part.

Beyond that, kinda hard to really troubleshoot by using text/messaging alone, so it may be time to have a Honda Dealer take a look in person; I'm confident a good tech and spot the actual source of the problem and get the engine running properly (and no longer leaking fuel).

Find a dealer in your area using this link. : Find a Honda Dealer

Truthseeker · Sep 23, 2014

As you said above, "You are correct about the float/needle controlling fuel flow." It does not make sense two new carbs would leak - period - but they have. Yes, there are a variety of things that could cause the engine to run rough and die, but how many of them cause fuel to leak and favorably respond to the motor being shook? Since the problem responds to physical shaking, it kind of logically eliminates potential issues that would not.

I appreciate your attempt to help. Unfortunately, you are as stumped as I am. Having a Honda dealer work on a mower this old is cost prohibitive. The money is better spent on going new. I want to know what the problem is whether I buy new or not.

robert@honda · Sep 23, 2014

Truthseeker said:
As you said above, "You are correct about the float/needle controlling fuel flow." It does not make sense two new carbs would leak - period - but they have. Yes, there are a variety of things that could cause the engine to run rough and die, but how many of them cause fuel to leak and favorably respond to the motor being shook? Since the problem responds to physical shaking, it kind of logically eliminates potential issues that would not.

One More Thing:

The carburetor on this mower is vented, and if that vent is blocked, it can cause the fuel the be pushed out, regardless of the float/needle status. The vent is a tiny "question mark" groove (highlighted in light blue below) cut into the side of a hard black plastic spacer on the intake manifold side of the carburetor. Installing this spacer backwards will cause the vent to be blocked. The gasket between the spacer and the carb body must also be fitted properly or the vent is blocked; I'd pull the carb off and triple-check that both the spacer and the gaskets are fitted correctly...pay close attention to the tiny hole on #13 and ensure it lines up with the matching holes on #11 and the large metal air guide insdie box #15...and of course, be sure the light blue groove in #11 is spotlessly clean too.

blacksmithden · Sep 28, 2014

Ok...one question. When you say "the carb is leaking"....where is it leaking from ? Is fuel coming out of the throat of the carb, or from somewhere else ? If it's coming out of the throat, the float/needle/seat are not doing their job. Fuel enters the carb via the float bowl. When the bowl is full, it's the float/needle/seats job to stop anymore fuel from entering the engine. Have you set the float height a little lower/the seating tab a little higher to make sure the fuel is shut off before the float gets to high and hits the underside of the carb ? If the needle doesn't seat before the float gets to the top, you're going to have a flooding situation all the time. Do you get brand new carbs where sometimes the float isn't set properly ? YES !!!! I've had a dozen over the years that did the exact same thing you're describing. Remove the float bowl....set the tab on the float a little higher so the needle seats when the float is a little lower in the bowl, and I bet your problem is solved.

Hope that helps....
BSD

Mikie19598 · Oct 6, 2014

robert@honda said:
So it only leaks when the fuel valve is open, correct? That would first indicate the source of the leak is after the fuel valve. There is a short length of fuel line between the fuel valve and inlet fitting on the carburetor. I'd inspect and likely replace that line first, and be sure BOTH ends of the line are secured with clamps/clips.

Does the fuel leak when the engine is off, or only when the engine is running?

You are correct about the float/needle controlling fuel flow, and it is normally a very reliable system. I highly doubt you got two new carbs both with defects. The governor regulates the throttle plate (maximum ending speed) and otherwise does not have any fuel-flow control.

Is the fuel leaking from the same exact location? How about some pics?

Im having a problem with mine not leaking fuel but it will idle up and down like it lopes and i think it just needs a carb kit installed with all ne gaskets but i can't find a kit for mine on the website it.s a troybilt with a Honda engine.

Mikie19598 · Oct 6, 2014

robert@honda said:
One More Thing:

The carburetor on this mower is vented, and if that vent is blocked, it can cause the fuel the be pushed out, regardless of the float/needle status. The vent is a tiny "question mark" groove (highlighted in light blue below) cut into the side of a hard black plastic spacer on the intake manifold side of the carburetor. Installing this spacer backwards will cause the vent to be blocked. The gasket between the spacer and the carb body must also be fitted properly or the vent is blocked; I'd pull the carb off and triple-check that both the spacer and the gaskets are fitted correctly...pay close attention to the tiny hole on #13 and ensure it lines up with the matching holes on #11 and the large metal air guide insdie box #15...and of course, be sure the light blue groove in #11 is spotlessly clean too.

can you tell me ware you got this diagram from i can use this for my card on my mower it looks like the same carb.

robert@honda · Oct 6, 2014

Mikie19598 said:
can you tell me ware you got this diagram from i can use this for my card on my mower it looks like the same carb.

On the side of the engine block you'll find the Honda Engine serial number. It will be in the form of "GXXXX-1234567" You need this full number to get the correct parts for your engine.

A whole new carburetor is likely to cost less than $20 for this engine, and is a lot less frustrating that trying to clean or rebuild an old one.

Use this link to find a Honda engine dealer who can get you a carb (or parts) as needed:

Find a Honda Engine Dealer

Honda Carb Problem - HRB216

More options

Truthseeker

Forum Newbie

robert@honda

Lawn Addict

Truthseeker

Forum Newbie

robert@honda

Lawn Addict

Truthseeker

Forum Newbie

robert@honda

Lawn Addict

blacksmithden

Forum Newbie

Mikie19598

Forum Newbie

Mikie19598

Forum Newbie

robert@honda

Lawn Addict

Footer Links 1

Footer Links 2