Carb Leaking - know where, don't know why

[mculik5]

Hi. New to this forum. Thanks in advance.

I have a 15HP Brush Master CH4 chipper that came with our new house. I have no use for it, so I'm selling it. It runs and works great, but has one issue that I'd like to fix before selling it. Whenever the fuel flow valve is turned on, the carb leaks from what appears to be some kind of drain port. I took it apart and found out where it's leaking from, but don't know what is broken that is causing this issue.

FYI, the engine is branded DEK and the carb has Yinba cast on the side of it.

I've attached a picture of what I've found. Here are the details:

1. Fuel is gravity fed from a tank several inches above the entire carb.
2. When the fuel flow valve is turned on, fuel enters at the hose barb at the end of the top arrow on the left and begins to fill the bowl (which was removed when I took this pic).
3. Because of the height of the tank, fuel completely fills the bowl and "bowl chamber" inside the carb.
4. At the very top of the "bowl chamber," there is a through-hole (circled in blue). There's no check valve or anything on either side of the hole. It's literally just a through-hole.
5. When the fuel reaches the height of the hole, it starts draining through the hole and down this weird, baffled pathway (drawn in blue) between the carb and the air filter connection which drains to the ground.

FYI, there are no other holes in the "bowl chamber" except for the needle valve. Also, to be clear, the needle valve is not leaking. The engine runs great and the fuel is distinctly coming from the drain port I mentioned above.

I'm guessing that the through-hole is to allow air to escape as the carb bowl fills. What I don't understand is what is supposed to stop the fuel from leaking once the bowl is full?

Thoughts? Again, thanks.

 

[ILENGINE]

Hi. New to this forum. Thanks in advance.

I have a 15HP Brush Master CH4 chipper that came with our new house. I have no use for it, so I'm selling it. It runs and works great, but has one issue that I'd like to fix before selling it. Whenever the fuel flow valve is turned on, the carb leaks from what appears to be some kind of drain port. I took it apart and found out where it's leaking from, but don't know what is broken that is causing this issue.

FYI, the engine is branded DEK and the carb has Yinba cast on the side of it.

I've attached a picture of what I've found. Here are the details:

1. Fuel is gravity fed from a tank several inches above the entire carb.
2. When the fuel flow valve is turned on, fuel enters at the hose barb at the end of the top arrow on the left and begins to fill the bowl (which was removed when I took this pic).
3. Because of the height of the tank, fuel completely fills the bowl and "bowl chamber" inside the carb.
4. At the very top of the "bowl chamber," there is a through-hole (circled in blue). There's no check valve or anything on either side of the hole. It's literally just a through-hole.
5. When the fuel reaches the height of the hole, it starts draining through the hole and down this weird, baffled pathway (drawn in blue) between the carb and the air filter connection which drains to the ground.

FYI, there are no other holes in the "bowl chamber" except for the needle valve. Also, to be clear, the needle valve is not leaking. The engine runs great and the fuel is distinctly coming from the drain port I mentioned above.

I'm guessing that the through-hole is to allow air to escape as the carb bowl fills. What I don't understand is what is supposed to stop the fuel from leaking once the bowl is full?

Thoughts? Again, thanks.

Either the float valve is actually leaking or the pathway between the fuel inlet and the float valve seat is cracked, which I have only seen once in 21 years.

 

[cpurvis]

The float chamber should not be completely full of fuel. It's the float and needle valve's job to prevent that. Check the float to make sure it is airtight; replace if necessary. Replace the needle valve (and seat, if you can).

 

[mculik5]

The float chamber should not be completely full of fuel. It's the float and needle valve's job to prevent that. Check the float to make sure it is airtight; replace if necessary. Replace the needle valve (and seat, if you can).

Thanks to both of you. I feel like an idiot. Should've Googled first. I didn't realize the purpose of the float was to shut off the fuel flow to the bowl and thought the needle valve was controlling fuel flow into the airstream somehow.

The float is not air tight. It's got fuel in it. Since the engine runs fine, I didn't think anything of it.

Now I've got to figure out if/where I can get parts.

Thanks again!

 

[david02777]

Did you ever figure out where to get parts (and a manual) for this motor? Thanks!

 

[bertsmobile1]

Did you ever figure out where to get parts (and a manual) for this motor? Thanks!

There is no service literature nor any parts for these lowest possible price engines, because it is the lowest possible price & warehouses full of parts cost a fortune and generally run at a loss. Ditto for producing manuals.
As designing & testing an engine also costs money all of these bottom price engines are copies of old engines that are out of patient or strait out patient thieft.

As Honda makes the best small engines just about all of them are Honda copies.
Thus all you have to do is work out which Honda engine DEK stole.
Some times they get a bit canny and mix parts from 2 different engines.

Once you have worked out this then you can go to an independent engine shop and get some after market Honda clone parts.
You can take pot luck and hopefully get parts that actually work and will in fact fit.
Don't bother with a Honda shop because they will need an engine & serial number to look up the part on the computer.

 

[david02777]

Thank you, I really appreciate the help. I've got the DEK engine number off their website - this may be an SKU or a number for the website, so I'm not sure if it will help me yet. (15 HP # E06910). I'm not too familiar with small engine types so I'll have to do some digging.

As for the production observations, I couldn't agree with you more. I've a bunch of years overseeing production in Chinese factories (machine shops) and I can see how this all unfolded.

Thanks again.

 

[Scrubcadet10]

omb wharehouse and gopowersports sell clone parts.

 

[bertsmobile1]

Thank you, I really appreciate the help. I've got the DEK engine number off their website - this may be an SKU or a number for the website, so I'm not sure if it will help me yet. (15 HP # E06910). I'm not too familiar with small engine types so I'll have to do some digging.

As for the production observations, I couldn't agree with you more. I've a bunch of years overseeing production in Chinese factories (machine shops) and I can see how this all unfolded.

Thanks again.

And we both know how it will end and it ain't pretty but greed is a basic human trait.
Without it we would not have outlived the dinosaurs..
A friends son has just finished a degree course in criminalogy.
He was taught that less than 10 % of thiefts happen because thiefs want whatever the item is they are stealing and in most cases that would be food.
The other 90 % gets sold to "honest" people

If you post a few photos those with a wider knowledge than mine might recognize the engine styling.

 

[david02777]

omb wharehouse and gopowersports sell clone parts.

Good to know, I will check them out, thank you.