Bolens ST120 engine SWAPPED!!

[sean'sengines]

I just swapped the 14.5hp OHV engine out of my Murray (briggs and stratton) into my ST120. Although, now I need the self adjusting fuel valve on the bottom of the fuel bowl. Hopefully I can get one soon. Then this baby is ready to mow!!

 

[benski]

I just swapped the 14.5hp OHV engine out of my Murray (briggs and stratton) into my ST120. Although, now I need the self adjusting fuel valve on the bottom of the fuel bowl. Hopefully I can get one soon. Then this baby is ready to mow!!

Very good! New life into your machine:thumbsup::biggrin:!

 

[sean'sengines]

Well I've got everything in and hooked up, now though, I just cant figure out why it's doing this!!! It's surging when running, and backfiring too. Not sure why. I've already rebuilt the carb. Any ideas?

 

[sean'sengines]

Here's a video of it!!! Help?!?!

 

[reynoldston]

How is your valve adjustment

 

[sean'sengines]

just did them today. .005 intake, .007 exhaust. It's a lot easier to start now, and it doesn't burn oil like it was, but it's still running crappy. (it burns a little oil still)

 

[benski]

A couple more ideas cropped up for me.
1. Is your spark plug in good shape?
2. Would the fuel shut off valve (solenoid operated) have an impact on how you're running?
3. Could it be that your plug wire is in bad shape and shorting out occasionally? (You might try firing up at night for a short time and see.)

 

[sean'sengines]

A couple more ideas cropped up for me.
1. Is your spark plug in good shape?
2. Would the fuel shut off valve (solenoid operated) have an impact on how you're running?
3. Could it be that your plug wire is in bad shape and shorting out occasionally? (You might try firing up at night for a short time and see.)

Spark plug is brand new. The wire is fine, and the fuel shut of valve (the solenoid one - I also have a manual shut off seen in the video) only has two positions. on or off. And everything in the bowl and stuff is clean. I guess maybe I could take it off again, take all the tubes and screws out, clean it out as best I can, and put it back together and reset all the screws to factory settings. But I think it goes deeper than that. What about the crank case breather (valve cover?) could that be causing some oil in the carb, hence burning would occur, or some fuel issue?