Cub Cadet HD2135 1996 Starting problem and ignition switch feels strange startng

Hi all,
I have a 1996 Cub Cadet HD2135 with a Kohler 12.5 HP engine. This Cub has the hydrostatic transmission. While mowing yesterday, after an hour and half, it started acting like it was running out of gas - the engine started hesitating like just before it stalls out but I was able to make it back to my garage. I shut it off and filled it up, but when I went to re-start - I got nothing. Thought it might've been overheated so I waited a while. Then when I turned the key, I noticed that not only did the key not engage the starter where it usually does, so I kept turning the key and did finally get it the starter to engage and the engine to start - although it was running very roughly. When I disengaged the choke, it immediately died. I was able to get it re-started a second time but had to keep engaging/disengaging the choke to keep it running...

I'm suspicious of the ignition switch, since everything was running fine up until I went to re-start and then I noticed that I had to turn the key an additional quarter-turn from where I normally felt the ignition switch engage the starter.
Was hoping someone would have some ideas on this and how bad/how much cost to swap out the ignition key switch - OR, if I'm completely barking up the wrong tree.
thanks,
greynold99

 

Having to apply choke is indicative of a carb problem. Either water or trash has gotten in the carb. The key thing is probably just the flat spot on the keyswitch got rounded off and allowed the switch to spin in place a little. (unless this has the plastic push-in switch, then the switch internals are getting worn).

 

Cheese,
You were spot-on with the key switch "rounding off" the 'Flat' built into the instrument-cover bezel where the key-ignition cylinder comes up through I believe that happening was just a coincidence and a red-herring to the real issue.

I don't believe it's a fuel or carburetor problem either and here's why. I did a quick fix on the key-switch by jamming a small flat piece of plastic between the instument-cover bezel hole and the round-cylinder of the Key-switch as it comes up thru the panel. With the 'flat' restored - the key operated normally in the switch. The darn tractor started right up. I ran it on idle for about 5 minutes and then decided, Well I didn't get all the mowing done - so, I took it out and mowed for almost an hour and then on one pass up a grade, it started to sputter till I had to disengage the mower deck. It kept running until my next pass up the hill. It then sputtered and died - and would crank to start but NOT start.
Well, I thought it must a heating problem (ignition coil maybe...?) So, I waited an hour, returned and it started right up and ran long enough for me to get back down the hill and inside my garage. I suppose I could've ran it another hour before it failed but it was getting dark by that time.

So do you think I'm on the right track with the ignition coil? Also, on a 16 yr. old tractor, 415 hours - would you recommend any additional maintenance - Carb rebuild comes to mind (which I was planning on doing anyways) and a new fuel filter. I change the oil every season, and the transmission oil/filter every two years (never just changing the filter as recommended in the Owner's Manual).
Can you give me an idea how complicated the carb rebuild will be and if I need to drain the gas out of the tank?
Thanks a lot, appreciate your help.
greynold99

 

Where is the fuel tank on this mower? Does this unit have a fuel pump?

If it idled for five minutes and then cut fine for an hour, only sputtering when going up a hill I don't think it's a coil or ignition problem. I'm wondering if the fuel pump is bad. On level ground gravity is able to get fuel to the engine but when you're aimed uphill the fuel tank is low and the engine is high, starving it of fuel. That is assuming you have a fuel tank in back and a fuel pump. If your fuel tank is located high up under the hood that's probably not it.

 

Sure doesn't sound like a coil problem to me. When you start up a slope, the fuel level in the carb bowl tilts, and if there is water in it that was out of reach of the main jet, it may be in reach when the level is tilted. Also, when going up a grade, it places a larger load on the engine which draws more fuel to meet the demand, and water or trash in the carb can get sucked up to the jet and cause stalling.

Fixing the carb isn't hard if you pay attention to what was taken off and from where. Take close pics with a digital camera before and during removal so you can have some reference to where everything was.

 

Thanks guys,
I've appreciated your help and expertise over the years and always take your posts as seriously useful information whether to me or to anyone else on the forum.

The problem I have with the fuel/carb and slope mowing as the problem is that the first time the tractor sputtered to a dead stop was on completely (well mostly completely) level terrain. That's when I thought it connected to the ignition cylinder 'spinning' in the instrument cover.
What I didn't mention on the followup post is that I had already gone up and down that 15 degree hill side 5-times before it sputtered on the 6th (which I recovered by disengaging the mower deck blades) and then on the 7th climb it sputtered and died. I know that still doesn't eliminate fuel/carb as problem but...

And, just like on the first occurrence - I waited an hour and it started right up. I would think a fuel/carb problem would be more consistent presenting; where a heating problem would disappear when the failing part cooled off.
But anyway, I pickup BOTH an ignition coil and a carb rebuild kit last night.
I'll replace the coil tomorrow and see if that fixes it and if not, rebuild the carb.

Just in case I'm close to the source of the problem, do you guys routinely replaced that little regulator/rectifier part when replacing ignition coil (if the engine has one)?
thanks,
greynold99

 

Once you install the coil, they probably won't take it back (just so you know). Just trying to save you some money. It's much harder to change coils than it is to check for trash in the carb.

When the coil is bad, I replace just the coil unless something else is also bad. Your engine has no rectifier/regulator that is related to the ignition system. Something's in your carb.

 

Cheese,
You got that right about the carb work being easier than the ignition coil change.
Although doing the ignition coil first, showed be how-easy the carb is going to be able to get to, if necessary...
And the price differential is right-on too - the ignition coil $55, carb rebuild kit $11 - no exchanges/returns, All sales final.
However, I'm glad I did the ignition coil exchange; just figgering out how-to-get-at-it was my lesson in humility. I eventually realized that the 'accordion-like' circular-shield between the front of the engine and the firewall (covering the drive shaft)- was made of some kind of plastic and could be 'squeezed' thru the firewall-hole so that you could move the metail engine cover/shield away to swap the ignition coil. I was starting to think I was going to have to drop the engine to swap a simple ignition coil.

Anyway, one thing I wanted to mention: on the ends of the 3 pre-formed metal-legs of the ignition-coil that 'almost but not quite' touch the flywheel there was a good bit of build up of oily grass/engine debris - enough to cause a false-touch condition. I'm wondering if I had problem with that gunk either acting as an insulator and keeping the proper voltage/current from generating OR, perhaps functioning as a 'conductor' at the higher heat-range, causing the coil to short-out on the flywheel.
Maybe nothing wrong with the coil at all.
Another thing I haven't mentioned earlier is that it seemed this past year that the engine didn't Start as easily or Run as strongly at Full throttle as I remembered. Even after new spark plug, oil change and new air cleaner installed. Although, I admit a fuel/carb issue could cause the same symptoms.
I ran out of daylight last night before I could get it all back together to test but will tonight - gotta get mowing with the past week's rains, I'll have a pasture to bale before long.
thanks again,
greynold99

 

I got everything put back together last night except for putting on the side-covers for the exterior of the tractor (just in case I had to do a carb rebuild) and started her up. The first thing I noticed was that with only the new ignition coil installed, the sound of the motor was quieter. I mowed for 2 hours and had no further problems. While not a fuel/carb problem, I'm not sure there was anything wrong with the old coil except for the gunk built-up on the front of the three 'legs' of the coil-armature that pass closely to the flywheel 'brush'.

I'll keep the carb rebuild kit but I'm popping on the side covers tonight. Since it didn't blow up on me or start burning (see You Tube for burning Cub Cadet 2135) on me (I did replace the fuel filter as well) I figure I got everything put back together correctly.
Only part I had left over was a small 5/16" star-washer that I hadn't noticed coming off any bolt. Thought it might've been from the one POS battery cable connection since you have (2) wires connecting to the battery - so that's where I used it.
Thanks again,
greynold99

 

Glad you got it!
__________

 

As I said earlier, I don't think there's anything wrong with that first ignition coil but I'm curious What made you think it was not a coil issue...?
Is it one of those cases where a coil will usually either work or not work; whereas a fuel/carb issue might work just enough to present with those same symptoms?
Thanks,
greynold99

 

Applying choke made it run, and it died when you let off the choke. That is a sure sign of a fuel problem. That was a fuel problem that apparently has now disappeared.