HD2135 Starting/Running and possible bad ignition switch

[greynold99]

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

 

[EngineMan]

I feel you may have two problems, 1 with the switch so replace that and 2 with the carb so give that a good clean.

 

[greynold99]

There was a problem with the switch but only with where it is mounted on the instrument cover panel. Where it comes up through the cover-panel the key switch had "rounded off" the 'Flat' built into the instrument-cover bezel where the key-ignition cylinder comes up through and is supposed to keep it locked in place. 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/wedging 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,
greynold99

 

[Rivets]

I agree that cleaning the carb is the first step. If you are mechanically inclined rebuilding the carb is not that hard. Just take your time and if needed take pictures as you go, to make sure everything goes back the way you took it off.

 

[greynold99]

The price differential between replacing the ignition coil $55 and the carb rebuild kit $11 is significant - especially with no exchanges/returns, All sales final.
However, I still feel pretty strogly that it's an 'electrical' and not 'fuel/carb' caused issue and I'm glad I did the ignition coil replacement/exchange; the hardest part was figgering out how-to-get-at-it with no service manual. 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 removed and 'squeezed' thru the firewall-hole so that you could move the metal 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-contact condition between the coil and flywheel brushes. 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

 

[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

 

[EngineMan]

Well you got her going again thats the main thing:thumbsup: can you pop up a link to your youtube video.

 

[greynold99]

Well you got her going again thats the main thing:thumbsup: can you pop up a link to your youtube video.

Here you go EngineMan - Took me a while to find it again... greynold99

The Cub Cadet Bursts into flames! - YouTube

 

[EngineMan]

Thanks for the link, that one is going to take more then a carb clean....:biggrin: