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Hank F.
Hank F., Technician
Category: Small Engine
Satisfied Customers: 14439
Experience:  Certified on Onan and Generac generators
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model# XXXXX bf-3cr/16004-b engine starts but will stay running

Customer Question

model# XXXXX bf-3cr/16004-b engine starts but will stay running for 15 seconds or so..longer if choked by hand.......had coil checked......replaced condencer/points....whats up?
Submitted: 7 years ago.
Category: Small Engine
Expert:  Hank F. replied 7 years ago.


It sounds like the carburetor is plugged up.

Has this set been sitting for a while?

The easiest way to test is to spray a little gas or carb cleaner into the carb to see if it will stay running longer.

If so, you will need to remove, disassemble and thoroughly clean the carb.

Hank F. and 2 other Small Engine Specialists are ready to help you
Customer: replied 7 years ago.

i tried that and it still doesn't stay running .....not sure if fuel pump is working properly........also it seems to not keep spark when looking for a used pump as i've had this one apart and theres a couple small springs on the bottom that are broke

Expert:  Hank F. replied 7 years ago.

You have tried spraying gas into the carb and it still will not run?


What exactly do you mean by seems to not keep spark when needed?


At the oil filter adapter base is a small round sensor with a single wire attached to it. This is the low oil pressure cut off switch. Disconnect the wire and insulate it so it can not touch ground. See if this will help keep the set running.

Customer: replied 7 years ago.
sprayed carb cleaner in but didn't seem to make a diff...put a mirror so to see points spark......... sometimes not there.........but it will start for a short time........hand choke seems to help a bit now fuel pump not putting out at all times
Expert:  Hank F. replied 7 years ago.

On the points, you may not always see them spark. It depends on the state of charge of the condensor.


If choking it helps, it means it is not getting enough gas. The 2 culprits are the carb and the fuel pump.


If the fuel pump is bad, it will need to be replaced. I doubt you will ever find a used one, and I personally would not trust a used one.


On the fuel pump are 2 wires, they should be black and tan. One is ground, the other is hot. Remove the fuel line from the carburetor and put it into a container of at least a quart. Jumper the hot wire directly to the battery terminal of the start solenoid and watch the flow. It should be strong and steady. If you happen to have a fuel pressure tester, it would be a good idea to pressure test the pump. It should have 3-4 psi pressure.


Have you checked the valves on this set? The intake should be set at .005", and the exhaust at .013".

Customer: replied 7 years ago.
i'll have to get back to ya........but have to say the only two wires going to the pump are on the same post.........i can jumper from the hot on the soldenoid to the pump and it does operate just not pump fuel steady at all it did before i took it apart
Expert:  Hank F. replied 7 years ago.


The 2 wires, one of them should come from hot, the other should go to the fuel shut off solenoid. Is this correct?

Customer: replied 7 years ago.
Expert:  Hank F. replied 7 years ago.

You will definitely need to get the fuel pump replaced.


Have you checked the valves yet?

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