Heeeeelllp!!! I need a long distance online diagnostic. My John Deere STX 38 is surgin' and sometimes quittin'. If it sounds like it's gonna quit and I get the deck shut off quickly enough it usually picks back up and stays runnin'. I checked the fuel filter...it's good. I checked the plug...it's good. Good spark too...when I tested it. I'm no mechanic...small engine or otherwise and the JD dealer closes at noon on Saturday (the buggers) Do ya think it could be the coil? How can I check that? If it is somethin' like that I gotta wait until Monday to get a part 'cause only JD carries JD parts around here. The buggers! So what do ya figure Poncho?....or anyone else in the know?
Oh yeah...I checked the oil...good. Checked the air filter...good. And ya can see the linkage to the carb movin' in sync with the surge/pulse...if that means anything. I wanna cut some grass dammit!
is your air filter clean?check the plug?any water in the fuel?i bet ol poncho can point you in the rite direction! these are just a few things that i allways check when my mower acts up.
Water in the fuel is always a possibility or even crappy fuel.
Could be a coil issue but not the first place I'd look. Should check it though. You'll need a digital VOM. Since I don't see Ponchie here, there's an article he copied and posted which is good info. I also have other info on checking coils but this should keep ya busy for awhile.............
Thanx fellas! The air filter is good...and it's not likely the fuel itself 'cause I tried regular, mid grade and hi-test nd it's the same stuff that we run in everything from our vehicles to our other small engines without issues. I'll check out that article. Thanx again.
Mine does the same thing to a certain extent......Engaging the mower deck takes a lot of power from the engine.......Make sure your belts are good and that your spindles on the deck are free and well greased....If a bearing on one of those spindles is tightening up, it will do that. Could be built up crap under the deck and around the spindles too.
Sounds lean. You may have to pull the carb bowl and see if the thing has little sediment particles in it.
Even with clean fuel and a good grade, todays gas leaves a layer of sediment and constricts the orifices and main jet so it runs leaner than it should.
Air cooled engines work that scenario harder so it's a possibility that you have to clean it out and get the air/fuel back up to snuff.
sounds like it is starving for fuel.. or if it has a govenor on the motor, that could be not letting the throttle advance enough, when the mower head is engaged,,
This is from someone that HATES to cut grass,, I would personally use this as a excuse to go buy that new state of the art mower with operator included in the sale price,,
-- Edited by Bad Rat on Sunday 26th of July 2009 01:44:03 PM
__________________ WOMAN WHO PUT HUSBAND IN DOG HOUSE < SOON FIND HUSBAND IN CAT HOUSE
Well, I couldn't wait for my son to get offa work so I went out there, got down on the ground...looked like a turtle stuck on it's back...and got it all greased. I pulled the bowl offa the carb and it was cleaner than some of the glasses I've drank outta. Since I was there I pulled the plug again and gave it a lil' scuffin' too. Fired up the ol' thing and it ran like a top for about 2 minutes then started with the surgin' and pulsin' just sittin' still. She completely dies after about a minute of that nonsense if I don't jam the throttle past "wide open" into choke. If I didn't know better I'd say that someone screwed with the carb settin's. I didn't check the coil yet for a coupla reasons...#1 I'm humped over like a hound humpin' a football from gettin' down and back up...#2 I don't have a digital tester. Gonna call my mechanic buddy to bring his tester and check 'er out for me.
I didn't see the surging part in your post before....Usually that is that the carb is gunked up.....either with dirt or gas has sat in it too long and it has formed a varnish that plugs up passages. You may have to take it apart, clean it out with some solvent and blow out the passages....that usually works for me.
The Deere is runnin' again! I rechecked everything, including the carb float and it all seemed great to me Then it kinda dawned on me the inline shut-off valve for the fuel! Sure enough, it wasn't lettin' enough through Switched that and cut the front yard...ran better than it ever did. Kinda embarrassin' Now if I can beat the rain today I'll cut the backyard.
well i'll be dang. thats allmost as bad as bad rat runnin out of gas!!hahaha. sounds like somethin i would do. well, its a little slow around here but its not borin!!
well i'll be dang. thats allmost as bad as bad rat runnin out of gas!!hahaha. sounds like somethin i would do. well, its a little slow around here but its not borin!!
I'll never live that one down
__________________ WOMAN WHO PUT HUSBAND IN DOG HOUSE < SOON FIND HUSBAND IN CAT HOUSE
My lil' stunt puts me right in there with ya Rat buddy. What can ya do huh? Both of us went right past the simple and obvious and into the unknown zone.
I need a long distance online diagnostic. 
My John Deere STX 38 is surgin' and sometimes quittin'. If it sounds like it's gonna quit and I get the deck shut off quickly enough it usually picks back up and stays runnin'. 
I checked the fuel filter...it's good. I checked the plug...it's good. Good spark too...when I tested it. 
I'm no mechanic...small engine or otherwise 
and the JD dealer closes at noon on Saturday (the buggers) 
Do ya think it could be the coil? How can I check that? If it is somethin' like that I gotta wait until Monday to get a part 'cause only JD carries JD parts around here. 
So what do ya figure Poncho?....or anyone else in the know?
Oh yeah...I checked the oil...good. Checked the air filter...good. And ya can see the linkage to the carb movin' in sync with the surge/pulse...if that means anything. 
Since I was there I pulled the plug again and gave it a lil' scuffin' too. Fired up the ol' thing and it ran like a top for about 2 minutes then started with the surgin' and pulsin' just sittin' still. She completely dies after about a minute of that nonsense if I don't jam the throttle past "wide open" into choke. 
I rechecked everything, including the carb float and it all seemed great to me 
the inline shut-off valve for the fuel! Sure enough, it wasn't lettin' enough through 
Now if I can beat the rain today I'll cut the backyard. 
