New carburetor Installed and it still won't run. Has good spark. It turns over when adding seam foam to the crank case. It won't turn over by adding sea foam directly to the carburetor but it did before I swapped the carb out. What could this problem be? This carb grabs fuel directly from the tank. All linkages are correct.
Briggs carb swap
- Thread starter Mike
- Start date
Big_Holla
Senior Member
Big_Holla
Senior Member
If I remember right, the generic setting is 2.5 turns out…..
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What ya working on?
You said directly from the tank, I assume this means it doesn't have a float bowl? If there is one is there fuel in it?
Will it fire without the air breather on the carb? While that is off put your hand over the air intake and see if you get suction on the intake stroke.
If you're not getting fuel through the carb take it off and blow through the fuel inlet nozzle. If it's a china replacement sometimes they are plugged with casting material or something.
You said directly from the tank, I assume this means it doesn't have a float bowl? If there is one is there fuel in it?
Will it fire without the air breather on the carb? While that is off put your hand over the air intake and see if you get suction on the intake stroke.
If you're not getting fuel through the carb take it off and blow through the fuel inlet nozzle. If it's a china replacement sometimes they are plugged with casting material or something.
She done fired up by me totally covering the carb opening.
There is a fuel pump built into the carb that fills the cup(bowl) in the top of the tank prolly needed primed
Big_Holla
Senior Member
Sounds like it. Surprised dumping Seafoam into the carb didn't create enough prime to get it sucking.
I assume you checked the fuel inlet line, no dry rot, cracks, correct size, so on and so forth. Some of those smaller engines/carbs are quite sensitive to fuel line inlets/feed lines. If it has a bubble fuel pump thumb primer, same thing, make sure no leaks, cracks, dry rot issue. If does have one, pull it off, check it, clean the area up pretty good, hopefully it has a reusable gasket, but if not, that too may be no good, and it's sucking air through it.
And finally, the exhaust could be plugged or carboned up, restricting outtake air flow. Might check that too.
Good luck Mike!
And finally, the exhaust could be plugged or carboned up, restricting outtake air flow. Might check that too.
Good luck Mike!
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If it started with your hand over the intake you're not getting enough fuel to make it fire. Your hand creates a vacuum through the fuel line to pull in more fuel. Once it's running it has enough suction on the intake stroke to suck fuel itself. You pulling the handle without blocking the carb doesn't create a high enough RPM to create enough suction to draw fuel. You're basically choking the motor of air flow to get it started. Same thing a mechanical choke does but your meat paw has a better seal.
Does the motor have a fuel pump? Might be a little square looking thing bolted on the motor. Those work by vacuum through a small hole in the back. Take it off and blow through it. It should make a duck sound and vibrate. While you have it off go ahead and spray some carb cleaner in the holes. Don't give it the full blast just enough to get some cleaner in there. If it has a little thumb screw on the outside take it off and look at the screen. It may be rusted.
Does the motor have a fuel pump? Might be a little square looking thing bolted on the motor. Those work by vacuum through a small hole in the back. Take it off and blow through it. It should make a duck sound and vibrate. While you have it off go ahead and spray some carb cleaner in the holes. Don't give it the full blast just enough to get some cleaner in there. If it has a little thumb screw on the outside take it off and look at the screen. It may be rusted.
I assume this is a piece of equipment sits for long periods of time between use. That is why I strongly believe you have an air leak issue within your fuel system, whether it be fuel lines or all kinds of gaskets that harbor/contain fuel to the carburetor, and then through the carburetor to the motor. Even an improper toque down of the new carburetor gasket between motor block and the carburetor itself can cause too much air into the whole system. It doesn't take much of an air leak to cause the problem you are describing. Even old fuel line not properly fitting correctly due to being dried out, can cause the same problem. When equipment such what you have, sits for long periods of time, without or very little fuel in it, gaskets and fuel lines will dry up, or become dry rotten, where there may be cracks, or even microscopic holes in them, where you will not be able to see them with the naked eye.
So, again, I believe your equipment is sucking too much air into the cylinder head, and possibly not flowing through it correctly. That is why I said to check your outtake/exhaust too. If you have enough carbon build up, or it's plugged for whatever reason, the will be enough restriction for hard start as well.
If you have starter fluid, to prime the entire fuel system after checking everything I mentioned previously, and all is good, pull the spark plug, do a couple of small quick burst of starter fluid inside the cylinder wall, put the spark plug back on and finger tighten it down. Attempt to start it. You may have to do this a couple of times in order to properly bring up fuel pressure throughout the entire system and to build some heat into the motor block, which will swell most all gaskets again, too prevent an air leak.
Once you to get it running, shut it off, and toque spark plug down. Start it back up. then you may have to adjust fuel & air jets on the carburetor in order to run correctly under load, and the fuel mixture is not too rich or too lean for the motor.
Again, good luck Mike. Wish you weren't so far from me, otherwise I'd run over to help you out.
So, again, I believe your equipment is sucking too much air into the cylinder head, and possibly not flowing through it correctly. That is why I said to check your outtake/exhaust too. If you have enough carbon build up, or it's plugged for whatever reason, the will be enough restriction for hard start as well.
If you have starter fluid, to prime the entire fuel system after checking everything I mentioned previously, and all is good, pull the spark plug, do a couple of small quick burst of starter fluid inside the cylinder wall, put the spark plug back on and finger tighten it down. Attempt to start it. You may have to do this a couple of times in order to properly bring up fuel pressure throughout the entire system and to build some heat into the motor block, which will swell most all gaskets again, too prevent an air leak.
Once you to get it running, shut it off, and toque spark plug down. Start it back up. then you may have to adjust fuel & air jets on the carburetor in order to run correctly under load, and the fuel mixture is not too rich or too lean for the motor.
Again, good luck Mike. Wish you weren't so far from me, otherwise I'd run over to help you out.
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Parts lookup and repair parts diagrams for outdoor equipment like Toro mowers, Cub Cadet tractors, Husqvarna chainsaws, Echo trimmers, Briggs engines, etc.
I just took a quick peek, Tough diagrams to see even after trying to increase size, but I will go through it here shortly, and if I see anything obvious, I'll report back.
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PartsTree - Home of OEM Parts for Outdoor Power Equipment
Parts lookup and repair parts diagrams for outdoor equipment like Toro mowers, Cub Cadet tractors, Husqvarna chainsaws, Echo trimmers, Briggs engines, etc.
Looking at the diagram. Does this carb bolt directly on the fuel tank and pickup fuel via a pickup nozzle?