23 hp v-twin Briggs only runs wide open.

[murph4231]

i purchased a used husqvarna 2348. Mower looks great has 153 hours run time on it. Problem is when I start the motor it runs wide open. Can't figure out what is causing it, all linkages and springs look fine and appear to be working properly. I tried using a piece of stiff wire to hold the governor arm up all the way. No change in the run status, runs wide open, regardless which position the throttle is in. Any hints or suggestions, please advise.

 

[bertsmobile1]

First thing is to get firmly in your mind.
The throttle lever opens the throttle wide open.
The governor closes the throttle down to the level appropriate for the load on the engine.
ie, they work against each other, not with each other.

Usually an engine running WFO will be either an air leak between the carb and the engine.
Or a failure of the governor .
Two most common govenor failures, broken connection spring or loose connection at the govenor shaft.
After that it is on with the scuba gear and some diving deep inside the engine.

 

[murph4231]

First thing is to get firmly in your mind.
The throttle lever opens the throttle wide open.
The governor closes the throttle down to the level appropriate for the load on the engine.
ie, they work against each other, not with each other.

Usually an engine running WFO will be either an air leak between the carb and the engine.
Or a failure of the governor .
Two most common govenor failures, broken connection spring or loose connection at the govenor shaft.
After that it is on with the scuba gear and some diving deep inside the engine.

Thanks for the info, checked and tightened the carb mounting bolts, spring is fine and the linkage is tight on the shaft. So it must be inside the engine.
What is it in the engine that can cause this problem?

 

[gainestruk]

With engine not running move govenor arm (have throttle set at full speed) you should see movement on carburetor throttle shaft, if no movement most likely wrong spring or spring not hooked up right, if you see movement start engine and with hand throttle in fast position you should be able to slow down engine moving governor arm, you also should notice it much harder to move if governor is working while running, if you can slow engine down you have a failure of govenor inside engine which will mean taking engine apart.

 

[Tinkerer200]

"No change in the run status, runs wide open, regardless which position the throttle is in."

First thing to do given your info above is to see IF the carb throttle butterfly is in place and moving. Screws holding it may have come out OR shaft may have broken.

Now, in your statement above are you talking about the actual carb lever OR you talking about the remote throttle lever?

Walt Conner

 

[murph4231]

With engine not running move govenor arm (have throttle set at full speed) you should see movement on carburetor throttle shaft, if no movement most likely wrong spring or spring not hooked up right, if you see movement start engine and with hand throttle in fast position you should be able to slow down engine moving governor arm, you also should notice it much harder to move if governor is working while running, if you can slow engine down you have a failure of govenor inside engine which will mean taking engine apart.

Thanks for the info, with the engine running I was able to control the engine speed by manually moving the governor arm. I guess it's into the engine I go. I assume I first drain the oil, remove the engine from the frame and turn it over then remove the bottom part of the engine housing. Is there anything I should expect to come flying out or will it come apart so I can see the gears inside similar to pulling the oil pan off a car engine?

Many Thanks
Murph

 

[murph4231]

"No change in the run status, runs wide open, regardless which position the throttle is in."

First thing to do given your info above is to see IF the carb throttle butterfly is in place and moving. Screws holding it may have come out OR shaft may have broken.

Now, in your statement above are you talking about the actual carb lever OR you talking about the remote throttle lever?

Walt Conner

Thanks Walt, turns out to be the governor inside the engine. I will be tearing it down later today. Have done many automobile engines but this will be my first lawnmower motor. Hoping things don't start flying out when I remove the bottom part of the engine. Don't have and can't find a shop repair manual. Any insight regarding what to expect or procedures would be greatly appreciated.

Murph

 

[gainestruk]

As you say you have done several auto engines you won't have any problem just take your time open it up and see what damage you have, if you have any problems just ask, most of us will help all we can, I for one is interested in what you find, my father Inlaw has the same engine and it might help me down the line :thumbsup:

 

[Lawnranger]

If you don't mind, please post some pictures of what you find - this will help those who have not seen this problem before and give us a thread to refer to.

Thank you

 

[Tinkerer200]

I can send you a Service Manual for your engine IF you like, address below, put in proper format and remind me model number and what you want. The sump gasket kit for your engine will cost about $22 - $24.

Walt Conner
wconner5 at frontier dot com