Just won't stay running

[Paul Boy 31]

Spent the day working on a stubborn horse.  Trying to get our snow thrower tractor running. Its a Briggs 16HP and I would rather work on a Kohler any day. I've eliminated a plugged gas line. Cleaned the carb and the only way it will run a few seconds is on starter fluid. Acts like its not getting gas above the gas line filter. What can it be?  What else should I try?

[gwest_ca-(File Mod) 11,270]

Service manual help? Guessing at the model you have

Garry

[ZXT 2,401]

Have you checked to see if you're getting fuel? Pull the hose off of the carb and crank it over. You should get fuel. If you don't, the fuel pump could be bad or the hose running from it to the crankcase could have deteriorated. 

[ol550 830]

Most likely the fuel pump check valves or needle valve stuck, Sneak the carburetor top off and see if fuel is getting there. 

[lynnmor 7,606]

Apparently you have just the fuel pump built into the carburetor.  When you switched carburetors, did you switch the entire assembly which includes the fuel pump?   It is possible that you had two bad or dirty ones in a row.

 

Pull the fuel line off and blow back thru it while listening for air bubbling in the gas tank.  That should verify that the line is open. Also, check that there is no air leak between the tank and the carburetor, that will allow air to be drawn in and not allow gas to be pumped.   If you have a good supply system, then get into the carburetor for cleaning and adjustment.

[Paul Boy 31]

Thanks for all the help. Will get busy on the fuel pump and carb again tomorrow. I've not replaced the carb yet but need to try again using some of these suggestions. I'll let you know/

 

[Paul Boy 31]

Well, its been a disappointing day. Pulled carburetor apart and front panel of fuel pump. Not a drop of gas is being pumped. I suspect that I will need to locate the entire unit, Here's the problem, I don;t know which carburetor to order for this model Briggs & Stratton 16HP twin. There are no model numbers on the motor, no numbers identifying the Wheel Horse on it anywhere. Bought it from a guy who did a paint job (poorly) and removed everything. Any suggestions would sure help me with this. What to do next?

[Paul Boy 31]

Here is a photo of the tractor with the blower installed, when it was running  It has a B&S 16HP twin engine.

[ZXT 2,401]

57 minutes ago, Paul Boy said:

Well, its been a disappointing day. Pulled carburetor apart and front panel of fuel pump. Not a drop of gas is being pumped. I suspect that I will need to locate the entire unit, Here's the problem, I don;t know which carburetor to order for this model Briggs & Stratton 16HP twin. There are no model numbers on the motor, no numbers identifying the Wheel Horse on it anywhere. Bought it from a guy who did a paint job (poorly) and removed everything. Any suggestions would sure help me with this. What to do next?

The diaphragm should be replaceable. Were you cranking it and checking for fuel while you had the front panel off of the fuel pump? I wouldn't suspect it would pump while it is apart. Did you check to see if the hose running to the fuel pump is in good shape to ensure that there are no leaks? The pump operates off of crankcase pressure and if that hose is bad, has a blockage, etc., it won't pump fuel. 

 

If the pump is indeed bad and you can't find a replacement diaphragm, you could get away with installing another fuel pump in line with the old one - this would be about a $7 solution. 

[ZXT 2,401]

I believe this is the kit you need for your fuel pump. It can be found cheaper on eBay, but the rules of the site say no craigslist or eBay ads, so here it is on Amazon. https://www.amazon.com/Briggs-Stratton-393397-Fuel-Pump/dp/B000A13FBU/ref=asc_df_B000A13FBU/?tag=hyprod-20&linkCode=df0&hvadid=167151490548&hvpos=1o2&hvnetw=g&hvrand=17241527959784484440&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1026874&hvtargid=pla-306140047883&psc=1

[Paul Boy 31]

Do you have any idea if the entire carburetor/with fuel pump is available? If so, how would I go about finding out a part number to order the entire unitas the fuel pump is actually built right onto the carb.

[lynnmor 7,606]

Would this one fit?

 

Perhaps these parts are more than you need.

 

If the current carburetor(s) have no damage, I would simply clean, adjust and replace gaskets as needed.  Rarely does the entire carburetor need replaced.

[Paul Boy 31]

If I were to try and install an inline fuel pump to see if I can get it running that way and bypass this bad one, what would I need?  This is not my area of expertise in restoring these old horses so I can use any advice that someone might have. I would love to get this old girl running for the fall/winter season.

 

Someone has suggested that this engine may be what they called a B &S 16HP Opposed twin cylinder instead of a V twin. What is the difference and would the type of inline parts I might need be different?

Edited September 21, 2019 by Paul Boy
missed a pharagraph

[Paul Boy 31]

22 hours ago, lynnmor said:

Apparently you have just the fuel pump built into the carburetor.  When you switched carburetors, did you switch the entire assembly which includes the fuel pump?   It is possible that you had two bad or dirty ones in a row.

 

Pull the fuel line off and blow back thru it while listening for air bubbling in the gas tank.  That should verify that the line is open. Also, check that there is no air leak between the tank and the carburetor, that will allow air to be drawn in and not allow gas to be pumped.   If you have a good supply system, then get into the carburetor for cleaning and adjustment.

 

[Paul Boy 31]

I have never changed the carb. Its the same one that was on the engine when I got it. It has a fuel pump that is attached/built into the carb and cannot come off from its stationary position. Is there a possibility of bypassing this original pump and still using the original carb?

[ZXT 2,401]

Paul, the fuel pump is part of the carburetor, yes, but It can be rebuilt easily using the parts I linked to above. Replacing the carburetor is unnecessary, and original carburetors are often better than the Chinese knockoffs you'll find for sale. You'd be better off buying the $7 OEM B&S fuel pump kit that I linked to, as it will be made of material that will work with ethanol gasoline. I can't say the same for a Chinese carb.

 

As for there being a possibility of bypassing the original fuel pump, read a few posts up where I suggested that. The original fuel pump would obviously still be in line, but it wouldn't be doing anything. All you would need is a pump like this: https://www.amazon.com/HIPA-CH17-CH25-CV17-CV25-CH730-CH740-CV730-CV740/dp/B00WPSFAFU/ref=sr_1_1_sspa?keywords=lawnmower+fuel+pump&qid=1569114940&s=lawn-garden&sr=1-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFYNlhTVUo1NkNKMVYmZW5jcnlwdGVkSWQ9QTA4NzI5MTIxNTBJTThSN0NCRUFJJmVuY3J5cHRlZEFkSWQ9QTA3MTI2MDAyVzJGRFFGNEFGVzFFJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

 

In order to use this, you'd pull the hose off of the bottom of the existing fuel pump and hook it to this pump, hook the supply line from the tank to it and then run a new piece of hose from this pump to the inlet of the old pump. It should then work. 

 

Also, I've suggested this a few times now. Have you checked the fuel hose coming from the crankcase to the fuel pump? Is it free of blockages and in good shape?

 

Another note, the engine you have is a B&S 16 HP I/C opposed twin. It is not a V twin and shares nothing with the newer V twins.

Edited September 22, 2019 by ZXT

[Paul Boy 31]

The fuel line coming from crankcase is free of any blockage. I will run a new line for all of the hoses when I get the parts I need for either rebuilding the old pump or running something like you have suggested above. I checked all lines and have fuel to the inline fuel filter. There does not seem to be any blockage but the pump seems to not be working at all. Had trouble with it starving for fuel when it was but away last spring, acting much like a car does when the fuel pump is going. That is as far as it goes. I have a bad hand on the left side and only have the use of the right one so my wife has to be my left hand. Wish I had two good hands as doing some of these things seem to take forever. Thank you for all of your suggestions and help. Much appreciated.

[ZXT 2,401]

Sounds like the fuel pump diaphragm has a hole in it. You just need the rebuild kit, or buy the fuel pump I linked to if that is easier for you! Either should work fine. 

Good luck!

[Paul Boy 31]

Have ordered the fuel pump as suggested. Today I will replace all of the fuel lines and see what happens. Pump should arrive late this afternoon.

[Paul Boy 31]

Worked on the carburetor again today. Its been installed but there is still some type of fuel issue. All new gas lines,(except for tank to fuel filter)  new carb, new fuel filter, new air cleaner. Starts, runs a few seconds and stalls out. I took a bit of gas and put it into a bottle. Closed off the gas line from the tank, dropped hose into bottle and tried again. Started right up and ran until I shut it down. Its there a screen somewhere in the only line that I didn't replace?  So, tomorrow its back to the remaining line. Any opinions as to what this might be?

[gwest_ca-(File Mod) 11,270]

Should be a screen on the valve. Can you remove the line at the filter and see if gravity will drain the tank? Should have a steady flow until empty.

 

Garry

[mrshaft696 131]

Does the engine have decent compression?

 

 

[Paul Boy 31]

The engine has always run beautifully, no problems there. It runs if its disconnected at the inline fuel filter and the line stuck in a bottle of gas. Just replaced the last fuel line from the bottom of the gas tank to the inline gas filter going to the carburetor. Still the same issue. If I remove the gas tank line where it comes out of the tank, is there a screen there that might be causing this problem. Also, the fuel filter in the gas line never appears to fill completely. Is it supposed to to be fully filled with gas? Not sure what to do next. Very frustrating.

[lynnmor 7,606]

Remove the valve under the tank.

 

Often a fuel filter will contain air.

[Paul Boy 31]

Still working on this issue a couple of weeks later. Will run fine while being gravity fed but refuses to run but a few seconds when hooked to either fuel pump. Does anyone have a different option for me to try?  How would I adapt this engine to run gravity fed?