new carburetor

[Tom kite 3]

I just put a new carburetor on my 520h/onan 20

it will not stay running unless the choke is on

need help what is wrong.

[lynnmor 7,415]

Did you put a Chinese carburetor on?  What was wrong with the old one?

[Tom kite 3]

chould keep it running i clean it and still not working right. I also replace the fuel filter.

had give full choke and even then was not right.

[lynnmor 7,415]

So you had the same problem with the old and new one?  Maybe you could better describe exactly what you have tried.

[Tom kite 3]

the way I can keep it running give some alot of choke.  And compression is 100 on 1 and 2

[Maxwell-8 4,362]

14 minutes ago, Tom kite said:

the way I can keep it running give some alot of choke.  And compression is 100 on 1 and 2

typically a bad supply of fuel, A hose pinced? Pre-filter in tank is clough up

[Tom kite 3]

ty will try that ty

[rjg854 11,599]

Are you leaking air around the throttle shaft? I hear tell if you spray some carb cleaner or wd-40 on the shaft and hear a change in the sound of the engine, that may be your problem.

[Tom kite 3]

I will check it out ty but it's a new carburetor 

 

Edited January 10, 2021 by Tom kite

[Handy Don 12,737]

47 minutes ago, Tom kite said:

I will check it out ty but it's a new carburetor 

 

Sadly, "new" is not a guarantee of "good."

Many low-cost replacement carburetors are manufactured to lower standards than the originals and can be difficult or even impossible to make work correctly.

That is the reason for the earlier questions about the source of the new carburetor and what happened to the old one that made you want to replace it.

The experience of many members here is that finding the problem with an original equipment carburetor and repairing it is often more successful than replacing it with a new one. 

Please share details of the problems you were having and what steps you tried. There is a good chance someone here will recognize the symptoms and have more specific suggestions.

[Tom kite 3]

I took off top haft of carb. and clean it with carb cleaner. Then went to every hold on the carb. Took out the set screw on the side clean that to . Then I clean the button of the carb.

I  put on new fuel pump to and a filter. also open port on the side clean that to. one more there was a lot gas stary out of the carb

.

 

[Handy Don 12,737]

Thanks for adding more information.

When you were cleaning, did you use carburetor cleaning fluid?  The best ones are under pressure and have a "straw" that you can use to squirt the fluid directly with pressure into the carb openings (be very careful to use eye protection when you do this!) Were you able to let the fluid soak in the carb for several hours? 

The fuel pump you mention, is that the one attached to the engine and the filter the one between the pump and the carb?

Is the filter transparent and, if yes, can you see fuel flowing through it when the engine is running (the filter will not "fill up", and the pump normally produces small "spurts" of fuel into the filter)?

I think the carb you are using has only one needle screw, and that is for the idle mixture. (The "set screw" on the side covers a fixed main high speed jet.)

On the original carb, that needle screw should be gently screwed inward until you feel resistance and then turned outward 1 ¼ turns as an initial setting.

There should be a small round disk set into the body of the carb directly above the needle screw. Is that in place, or is there a hole in the side of the carb in that spot?

Can you take a close-up and clear picture of the side of the carb with the needle valve screw and post it here, please?

Edited January 11, 2021 by Handy Don

[richmondred01 2,270]

Did they send you the correct carb?

lots of the knock offs fit but they are the same for the p216, p216 and p220.

However, each one is jetted differently. 
im just saying you may have bought a p220 carb but in reality it’s a p216 carb. 
Something to consider.
 

[daveoman1966 3,762]

MAYBE...  You have a leak(s) at the intake manifold to cyl block gasket?  If so, it'll get too much air for combustion and using full choke would help cure that. When running, or while cranking it to start, spray some starting fluid onto the gasket(s).  If it revs up, bad gasket seal.     

[Tom kite 3]

15 hours ago, Handy Don said:

Thanks for adding more information.

When you were cleaning, did you use carburetor cleaning fluid?  The best ones are under pressure and have a "straw" that you can use to squirt the fluid directly with pressure into the carb openings (be very careful to use eye protection when you do this!) Were you able to let the fluid soak in the carb for several hours? 

The fuel pump you mention, is that the one attached to the engine and the filter the one between the pump and the carb?

Is the filter transparent and, if yes, can you see fuel flowing through it when the engine is running (the filter will not "fill up", and the pump normally produces small "spurts" of fuel into the filter)?

I think the carb you are using has only one needle screw, and that is for the idle mixture. (The "set screw" on the side covers a fixed main high speed jet.)

On the original carb, that needle screw should be gently screwed inward until you feel resistance and then turned outward 1 ¼ turns as an initial setting.

There should be a small round disk set into the body of the carb directly above the needle screw. Is that in place, or is there a hole in the side of the carb in that spot?

Can you take a close-up and clear picture of the side of the carb with the needle valve screw and post it here, please?

 

13 hours ago, richmondred01 said:

Did they send you the correct carb?

lots of the knock offs fit but they are the same for the p216, p216 and p220.

However, each one is jetted differently. 
im just saying you may have bought a p220 carb but in reality it’s a p216 carb. 
Something to consider.
 

j

[Tom kite 3]

thats the new one

[Tom kite 3]

15 hours ago, Handy Don said:

Thanks for adding more information.

When you were cleaning, did you use carburetor cleaning fluid?  The best ones are under pressure and have a "straw" that you can use to squirt the fluid directly with pressure into the carb openings (be very careful to use eye protection when you do this!) Were you able to let the fluid soak in the carb for several hours? 

The fuel pump you mention, is that the one attached to the engine and the filter the one between the pump and the carb?

Is the filter transparent and, if yes, can you see fuel flowing through it when the engine is running (the filter will not "fill up", and the pump normally produces small "spurts" of fuel into the filter)?

I think the carb you are using has only one needle screw, and that is for the idle mixture. (The "set screw" on the side covers a fixed main high speed jet.)

On the original carb, that needle screw should be gently screwed inward until you feel resistance and then turned outward 1 ¼ turns as an initial setting.

There should be a small round disk set into the body of the carb directly above the needle screw. Is that in place, or is there a hole in the side of the carb in that spot?

Can you take a close-up and clear picture of the side of the carb with the needle valve screw and post it here, please?

 

[richmondred01 2,270]

Is it a Nikki carb?

If so it should have it stamped into the carb along with part number. 

[Handy Don 12,737]

1 hour ago, Tom kite said:

thats the new one

Hello.

 

Also interested in @richmondred01's question about whether either or both carbs are Nikkis.

 

At the same time, please look carefully at both your old and new carbs where I've pointed with the red arrow and compare them to the same place on a working carb (mine!) in the next image.

From the image of your new one, it looks like there is hole into the body of the carb and on mine there is a plug of metal covering that hole.

That is a Welch Plug and it seals off that hole for both air and fuel. Without it, the carb cannot function correctly and the engine will never run without choke (nor will it idle or run at full throttle correctly).

Let us know what you find.

 

   

[Tom kite 3]

old carb.

[richmondred01 2,270]

What markings are on the new carb?

 

[Tom kite 3]

49 minutes ago, Handy Don said:

Hello.

 

Also interested in @richmondred01's question about whether either or both carbs are Nikkis.

 

At the same time, please look carefully at both your old and new carbs where I've pointed with the red arrow and compare them to the same place on a working carb (mine!) in the next image.

From the image of your new one, it looks like there is hole into the body of the carb and on mine there is a plug of metal covering that hole.

That is a Welch Plug and it seals off that hole for both air and fuel. Without it, the carb cannot function correctly and the engine will never run without choke (nor will it idle or run at full throttle correctly).

Let us know what you find.

 

   

 

[richmondred01 2,270]

 Emissions style

[Tom kite 3]

9 minutes ago, Tom kite said:

 

new one

[Handy Don 12,737]

It looks like a pre-emissions carb (no external accelerator pump) and that the welch plug is in place (red arrow).

But I'm wondering what's going on where the idle jet screw is supposed to be (blue arrow). The image isn't clear but it looks like corrosion and an exposed jet seat or a broken off needle screw.