Can't get mower to run right

[misha84]

What about fuel filter? Old fuel filter is no good.

 

[peabodyn]

What about fuel filter? Old fuel filter is no good.

The mower will run fine if I keep the throttle linkage pushed to the front of the mower.

What does this mean?

Is there something that is set up incorrectly?

Do I need to get a new carburetor?

I hope the pictures have attached.

Thanks

 

[bertsmobile1]

Did you read the manual that Mark pointed you to ?
The thing you have the clamp on is the govenor arm and that is attached to the throttle butterfly.
The choke is at the front of the carb.
I choke you by shoving someting in your mouth not your bum :laughing:
If that is moving back & forth then it is doing what it is intended to do.
If the engine is surging, revving up, dieing then reving up again you are not getting enough fuel into the engine for the volume of air.
So ither there is a restriction in the carburettor preventing the fuel from flowing through.
or
The float level is too low so the wind passing by can not suck enough up
or
there is an air leak somewhere between the emulsion tube and the inlet valve.

 

[peabodyn]

Did you read the manual that Mark pointed you to ?
The thing you have the clamp on is the govenor arm and that is attached to the throttle butterfly.
The choke is at the front of the carb.
I choke you by shoving someting in your mouth not your bum :laughing:
If that is moving back & forth then it is doing what it is intended to do.
If the engine is surging, revving up, dieing then reving up again you are not getting enough fuel into the engine for the volume of air.
So ither there is a restriction in the carburettor preventing the fuel from flowing through.
or
The float level is too low so the wind passing by can not suck enough up
or
there is an air leak somewhere between the emulsion tube and the inlet valve.

When I took the carb apart the first time, I noticed that someone had used some sealant on the bowl gasket that was degraded by gasoline.

I suspect pieces of the sealant were sucked up into the internal passages of the carb and that I have not been able to clean them out, despite taking it apart and cleaning it out.

It looks like it's time for a replacement carb.

 

[bertsmobile1]

Yes, silicon has a place, behind an electrified fence topped with razor wire and all who access it should do a two year course after a qualifing IQ examination.
OTOH I make a lot of money cleaning t out from where it never should have been used.

Check for air leaks by putting some WD 40 or similar in a TRIGGER SPRAY BOTTLE and while the engine is running liberally spray it around the carb and engine manifold.
If the engine reacts then you have an air leak.
Check the float level as per the instruction in the manual Mark directed you to.
Clean the carb FUEL Passageways as per the same manual then adjust the govenor also according to the manual Mark directed you to.
When you have finished install the carb with nice new gaskets and a new float bowl gasket.
Start the engine
I it still acts naughty, hold the govenor rod flat out .
If the engine runs fine then check the govenor settings again.
If the engine misses and sounds like it is running out of gas then replace or rebuild the carb.
It is a bit of a moot point now days as the rebuild kits are usually 1/2 the price of a new carb.

 

[peabodyn]

I put the new carb on the mower today.

The mower still runs poorly.

Hard to start and spits and stumbles and has low RPM's.

Does the governor need to be adjusted? If so, how?

Suggestion?

Thanks

 

[Marty013]

i think youd need to be 110% sure your using the proper holes for linkage from governor to carb etc.. not nessarily the same ones you removed it from ( in case previous mech fudged it) and to ensure your not seeing any air leaks down stream ( carb to manifold, manifold to head.. head to block..) is the valve lash in spec?? are you 110% sure the problem IS fuel delivery? could it be something in the ignition grounding out and causing misfires?

i wish i had that eureka moment for you.. i know these issues are troublesome to track down

 

[peabodyn]

I took a propane torch and without lighting the gas, held it close to the carb, and manifold to see if it was sucking air.

There was no change in the idle, so I don't think its sucking air.

There is only one hole for the throttle linkage so I don't think that is the issue.

If I manually hold the throttle open I can get it to run ok.

I don't think the issue is ignition as it will start and run OK if I hold the throttle open.

I suspect the governor needs adjustment, I will get a tachometer so I can set the idle speed correctly.

I wouldn't know where to begin to check the valve lash.

It's frustrating..... I bought this mower 'cause it was cheap and thought it would be an easy fix.

Thanks for your input!

 

[Marty013]

its possible your dealing with a broken governor mechanism inside the engine... only one hole in the carb for linkage huh.. is it the proper linkage?? is it bent??

when its running, take that unlit propane torch and falow the intake tract with it... head gasket too.. any change in engine RPM means your onto something here

 

[peabodyn]

Will try again with the unlit propane torch.

Replacement carb is identical to original, no concern that the linkage is wrong.

Haven't had the time (or inclination) to play around with the mower. Will make time next week.

Thanks for the response.