How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Curtis B. Your Own Question
Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 26030
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
30244710
Type Your Small Engine Question Here...
Curtis B. is online now
A new question is answered every 9 seconds

Have a &S 311777 OHC engine. Have adjusted & readjusted valves

Customer Question

Have a B&S 311777 OHC engine. Have adjusted & readjusted valves (.04 & .06) and cleaned carb including replacing bowl gaskets & the left & right mounting gaskets. I've also replaced the solenoid/valve that screws onto the bottom of the bowl. It sputters every couple of seconds but continues to run. Any suggestions?
Submitted: 8 months ago.
Category: Small Engine
Expert:  Curtis B. replied 8 months ago.
Is this gravity fed from fuel tank, or is this have a pulse fuel pump.
Customer: replied 8 months ago.
Gravity
Expert:  Curtis B. replied 8 months ago.
Does it ever quit. or just sputters?
Customer: replied 8 months ago.
Gravity. I have cleaned out the fuel tank and replaced the fuel filter.
Expert:  Curtis B. replied 8 months ago.
If you remove the fuel hose at the carburetor, do you get 1/4 cup in 15 seconds ?
Customer: replied 8 months ago.
It doesn't quit, just sputters every couple seconds.
I get 1/2 cup in 15 seconds.
Expert:  Curtis B. replied 8 months ago.
Plenty of fuel! Any other symptoms? When did it last run without sputtering? You could have a valve that is not seating properly.
Customer: replied 8 months ago.
Ran fine couple weeks ago and then wouldn't start a few days later. See initial description to see all tasks done since then.
How can I determine if valve seating is problem?
Customer: replied 8 months ago.
Is there a fuel additive that might clean the valves?
Customer: replied 8 months ago.
I am using non-ethanol fuel now. Was using ~10% ethanol before.
Expert:  Curtis B. replied 8 months ago.
Nothing will clean the valves, if that is problem, the head would have to be removed and the valves reseated. Do you have the old solenoid from base of carburetor? Take it and cut the tip off it and install in the carburetor as a dummy, for test.
Customer: replied 8 months ago.
The old solenoid is a fuel shut-off valve: open when key is on; closed when key is off. Tip can't be cut off.
Expert:  Curtis B. replied 8 months ago.
It can be cut off, it is not a shutoff valve, it is anti-backfire valve, It does plug the main jet when key is shutoff m but does not shut off fuel to carburetor.
Customer: replied 8 months ago.
Sorry, it's not a "fuel shutoff". I was told, because there was oil 4" up on the dip stick, that the solenoid/valve was either stuck open or that it was not seating in the carburetor and that I had gas in the oil which kept it from starting. I replaced the solenoid, drained & replaced the oil & filter & adjusted the valves (.004 intake/.006 exhaust).
Expert:  Curtis B. replied 8 months ago.
You were told wrong, Fuel in the oil is the needle valve and float leaking. Not the anti-backfire solenoid. But it can cause starting and running problems.
Customer: replied 8 months ago.
So how do I resolve the needle valve and float leaking?
Customer: replied 8 months ago.
Also, would the needle valve & float leaking cause the engine to sputter?
Expert:  Curtis B. replied 8 months ago.
You replace the needle valve and seat, or just shut off the fuel between uses, Do you have fuel shutoff from tank? It will only leak when engine is not running.
Customer: replied 8 months ago.
I do have a shut-off valve but the current problem is that the engine sputters. Does a leaking needle valve and float cause the engine to sputter?
Expert:  Curtis B. replied 8 months ago.
I doubt it. I wanted you to remove the anti-backfire solenoid and check with dummy in place!
Customer: replied 8 months ago.
I don't see how I can create a dummy solenoid from the old solenoid because it only disengages when the key is engaged (voltage applied). I know the solenoid works because I tested it before installation. It may not seat correctly. How would I check that?
Expert:  Curtis B. replied 8 months ago.
The solenoid is supposed to retract when key is turned on. The thought is that the solenoid is relaxing and is not staying fully open. Not that it does not seat properly. You make it a dummy by ripping or cutting off the tip and installing it, and leaving the wire off.
Expert:  Curtis B. replied 8 months ago.
My response shows as customer!
Customer: replied 8 months ago.
The new solenoid works because I tested it before I installed it.I'll get a new needle valve & seat.
Expert:  Curtis B. replied 8 months ago.
OK>