LT15Wide Not Starting After 1 Month Idle

[Pepe_Silvia]

I wasn't able to run my saw for about a month, and now it won't start.  I don't know how old the fuel was, but at most a couple-few months old. I can get it to fire with carb cleaner and checked that it is pumping fuel into the carb, so I think that basically narrows it down to the carb being gummed up.

First of all, I typically just shut it down after use, but I'm thinking maybe I need to start shutting off the fuel shutoff and letting it starve itself, is that correct?

Second, is there a 'quick fix' on this?  Maybe one spot where it's prone to gum up that I can get to without taking the whole carb apart?  That's probably wishful thinking.

Saw is an LT15Wide with the 25HP Kohler.

[Just Right]

You could try SeaFoam to see if that helps.  Other than that,  rebuild the carb.

[Southside]

I let my welder sit once too long, same engine, and it was just a case of taking the carb off and cleaning it really well.  

[John Bartley]

One month should not be anywhere near time enough to gum a carb with bad fuel.   My guess would be water in the carb bowl.  Try doing a carb bowl rinse first.  If there's a drain screw do that first, then only remove the bowl if you have to.

EDIT : a 25hp Kohler will not likely have a drain screw.  You could start it and keep it running with a squirt bottle while you choke it to suck the water out of the bowl.  I can't believe that fuel could go bad in a month.

[Chuck White]

I have a 25hp Kohler on my mill, but I don't remember if there's a drain plug on the bottom of the carb, but if there is, drain it and feed it some fresh gasoline!

I only use 91 octane, non ethanol gas in my small engines!

[Pepe_Silvia]

Thanks for the advice everyone.  I took the carb apart and cleaned it as suggested and it works now.  So either bad gas or water.  There was some green corrosion on the interior parts.  Is this indicative of water?

There turned out to be no drain on it.



 

[charles mann]

for copper/brass, green is indicative of corrosion, aluminum, white. as recommended, run a little seafoam even though you got it running. my miller has a kohler and i let it sit for a while too, but my fuel tank is below the engine. i poured a couple bottles of denatured alcohol in the tank, put 5 gal of 100LL av gas and let it sit for a couple hrs. since the lift pump is whacked, i installed a primer bulb from a boat fuel tank, primed it, turned it over and it fired right up. i now only run 100LL in ALL my air cooled engines, including my chainsaw. 

[firefighter ontheside]

I’ve never ran my kohler engines dry of fuel, but I do shut off the fuel petcock.  My mower always starts fine the next spring.  If you’re going to let it sit that long, put a little bit of sea foam or other stabilizer in once in a while.

[Magicman]

There turned out to be no drain on it.

I'm surprised because most small engines have a drain screw on the bottom of the float bowl. 

[Pepe_Silvia]

There turned out to be no drain on it.

I'm surprised because most small engines have a drain screw on the bottom of the float bowl.

I don't know a whole lot about them, but this seems to be a little bit different design.  The bowl is basically part of the body of the carb.  There's a solenoid on the side (it attaches where the brass part is in my original post) that could probably be removed to drain the bowl, but I'm not sure the screws are accessible while the carb is mounted.
This isn't my picture but I snagged it from a youtube video I watched.


 

[Ed_K]

 I had problems with my garden tractor not starting if not used every day. It ended up that electric shut off on the side of the carb was sticking. Just a little sticky film on it and it wouldn't open. Not saying what happened to that rod .

[Don P]

On the denatured alcohol thing, I've removed the fuel pickup tube from the tank and stuck it in a bottle of fuel treatment (denatured alcohol) and sucked up a very healthy snort. The alcohol will mix with water and also mixes with gas so it soaked up the water that was in the bowl and it got burned over the next couple of minutes of rough running.

[Pepe_Silvia]

Well, it wasn't actually running as well as I thought.

When putting the carb back together the gasket was curling on me and would not seat properly.  I got it back in as best as I could.

It would run at first, then got to where it was dying every time I throttled down.

Eventually it stopped running and would cough but not start.

I ordered a new gasket, got it in today.  Went ahead and siphoned all the old gas out of the tank as best as I could, unhooked the fuel line and cranked the motor a few times to clear the line.  When I was putting it back together, the spring that wraps around the throttle and is connected to the carb and linkage came off, and I'm not 100% sure I put it back on in the right place.

At idle now it cycles between idling well and almost dying.  At full throttle it surges.  When I throttle down from full throttle it dies.

I'll try to take some video if that will help.

[btulloh]

That spring must be related to the governor and you probably put in the wrong place so the engine is hunting. 

Do you have a manual for the engine?  Or you should be able to find it on a parts diagram online. 

Sounds like the gasket and the other things you did took care of your original problem. 

[Pepe_Silvia]

I found the manual here: http://www.kohlerengines.com/engines/onlinecatalog/pdf/24_690_06_EN.pdf

It is the spring that's on part F here, the throttle linkage.  It looks like I have it in the right place.


 

[Ed_K]

 I found that when my engine was surging/hunting the float was not set right.

[btulloh]

X2 on the float.  I'm not a real good carb guy and I always think the float is adjusted OK because I didn't change it when I'm rebuilding a carb.  I'm usually wrong.

The real story is everything needs to be right with the carb and linkage and it's easy to miss something.  If the original problem was a gummed up carb, it's also easy to miss cleaning some of the tiny internal passage ways.  

Another thing that gets skipped with a casual cleaning is removing the Welsh Plugs - the little domed things that look fragile (they are). They are usually supplied with a rebuild kit.  Removing them allows access to the internal passage ways that like to gum up.

[sealark37]

Just a re-cap of the obvious.  Are you using ethanol-free gas?

[Pepe_Silvia]

Just a re-cap of the obvious.  Are you using ethanol-free gas?

I'm not.  Ethanol-free is not readily available around here. 

[Pepe_Silvia]

I found that when my engine was surging/hunting the float was not set right.

Thanks for the tip.  I've never adjusted a float before, but I'll search and see what I can find.

Any tips?