Cub Cadet 1330 with 190-350 snow blower won't start

[fhiggenbottom]

In getting my Cub Cadet 1330 with a 190-350 snow blower mounted on it ready for the snow season the Kohler 12.5 hp engine wouldn't start. In response I started a diagnostic and discovered that it had spark and would run on starting fluid. Assuming it was a plugged carburetor I ordered a new one on line. When it arrived I installed it verifying an ample supply of fuel to and from the gas filter but also replaced the fuel filter and spark plug when I installed the new carb. After that t now won't start even using starting fluid. I verified it has spark and although not conclusive placing my finger in the sparkplug hole it seems to have good compression. I reinstalled the old carburetor as an experiment and even with starting fluid it too wouldn't allow the Kohler 12.5 hp engine to start. It has spark, appears to have compression and good fuel flow and even with a new sparkplug, new carb, new fuel filter and fresh gas it won't start. Could it be a safety switch? And if so how should I proceed to find it. Any suggestions?

 

[spndncash]

if you cover the carb air intake with your hand when you crank does it pull a vacuum? if not its either got an intake leak, or an internal problem with the engine - rings, valves, cam, hole in the piston, etc etc etc.
and yes it could be a safety switch or other electrical demon - but I dont know your circuit well enough to diagnose. Every thing I have wont crank without the safeties made.

 

[mgonitzke]

If it has spark, compression and fuel, the only thing left is timing. Check to see if the flywheel key sheared.

 

[tkhoffman]

When was the last time it ran? How fresh is the fuel in the tank? Spark means it's not a safety switch.

 

[gary noblit]

Fred,you didn't say how long since it ran,assuming it did when parked.You did not say you drained old gas and lines.It doesn't take much condensation to ruin gas and it doesn't take much to ground a plug internally.Simple but functional compression test:round handle screwdriver held snug on plug hole should produce a loud hiss.If it does you have some compression.I never use starting fluid,it evaporates quickly and too much has a host of problems.Try carb. cleaner spray after you have drained every thing including carb. Todays ethanol creates issues.....It is till possible timing issue but was it running when it was parked???

 

[fhiggenbottom]

My Cub Cadet 1330 is equipped with the Kohler 12.5 hp engine and it ran well when I parked it two seasons ago. Reviewing, the steps taken after it wouldn't start: I first squirted starter fluid in the carb and it ran for a few seconds each time that I did that. I surmised the carburetor was plugged from sitting for two seasons and instead of rebuilding it ordered a new one on line. When it arrived I replaced the carburetor, drained the fuel tank, cleaned the rubber fuel lines with carb cleaner, replaced the fuel filter, gapped and installed a new spark plug, and placed enough fresh gasoline in the tank to start it. I also verified that the fuel line from the tank was freely delivering fuel to the fuel filter and that the fuel went through the new fuel filter to the carburetor. I verified that the new plug had spark by spinning the engine and observing spark at the plug tip with the plug grounded against the engine.

The flywheel key doesn't appear sheared because I can rotate the engine by hand and feel resistance which indicates at least some compression. I don't have a compression gauge and can't take a definitive measurement of compression but in placing my finger over the spark plug hole feel a considerable amount of compression which makes it impossible to keep my finger over the hole. After all this, the engine wouldn't start even using starting fluid. If I can figure out how to remove the engine hood when the weather warms up without having to remove the snow blower from the tractor (what a pain) I'll remove the sheet metal over the engine and confirm that the flywheel key isn't deformed or partially sheared.

Unless I can figure this out, I guess my next step is to take it to the Cub Cadet service repair shop and suffer costs of $80 an hour in labor plus their high priced parts with the obligatory sales pitch for me to buy a new or used mower/snow blower from them.

 

[tkhoffman]

Carb cleaner in the fuel lines.... No good. Take the bowl off the new carb and see if it is loaded with gooie rubber.

 

[mgonitzke]

Keep in mind that the torqued flywheel bolt preloading the taper interface between the end of the crankshaft and the flywheel is what is keeping the flywheel in position, not the key. The key is there to index the flywheel correctly for proper ignition timing. The key can be sheared (by a backfire or sudden engine stoppage) but the flywheel is not loose on the crankshaft.

Starting fluid is hard on engines. A squirt can with some 2-cycle mixed gas in it would be a better idea. I'm going to speculate that it either preignited or backfired when you were trying to use starting fluid on it, which sheared the flywheel key and shifted the flywheel just enough that the timing is either advanced or retarded too far for it to start.

 

[etopel]

While anything's possible, I doubt the flywheel key is sheared. Have you tried your old plug again? It's rare, but I've had new plugs that would spark outside the engine but wouldn't under compression.

 

[gary noblit]

Fred, one last thought..Does carb. have elec. solenoid.If it does you have to prove it is working as well.It should "click" when key is turned on. Everybody has offered great advice so far.Step by step prove everything including timing key.It will run....

 

[fhiggenbottom]

Thanks for to all for the helpful advice and moral support. I finally got the Kohler 12.5 hp engine to start!

Smelling a strong odor of gas after returning to continue working on this engine and diagnose the problem, I discovered that gas had leaked into the oil. The new carburetor (from China) was faulty and had leaked a rather large amount of gas into the oil and engine. It had flooded the oil pan and engine block just short of causing hydraulic lock or even worse an engine fire which proved the reason it would not start.

Switching to another carburetor, changing the oil filter and giving it a fresh oil change to remove the gas resulted in the engine starting. But in the process of removing and replacing the carburetor the throttle linkage became disengaged from the governor. Reattaching it proved a frustrating chore given the tight spaces and plastic retainer located on the linkage rod that clipped between the governor and engine block to secure the rod. But after reinstalling it and reattaching both it and the choke linkage to the carburetor the engine started.

But the saga continues. To my surprise the engine ran only at full throttle having no throttle control. I confirmed that the throttle control lever moved the carburetor throttle before completing the button up and now I'm totally stumped. I don't understand the genesis of the new problem but logic dictates that it has to emanate from the throttle linkage and governor mechanism. Frustrated I gave it a rest last night and will try to diagnose and resolve the problem today. Has anyone else encountered this problem?

 

[gary noblit]

Fred,My question is gov. spring still hooked ??I'm sending a pic but don't know if it will help.My engine(same) is upside down waiting for crank seal. best advice is get next to another 12.5 for comparison of linkage.The gov. spring shows up brown in the pics.Note: I put on carb. with elec solenoid to avoid flooding issues,of course you have to run a hot wire to it from switch.Your flooding is very common and can be very dangerous.Even old carbs leak when needle wears out.I'm a voice in the wilderness when it comes to this issue on gravity fed gas.Mfg should have long ago put a stop to this with an auto shutoff or at the very least a manual one...

 

[fhiggenbottom]

Problem solved! I discovered that the carburetor I replaced the leaking one with was slightly thinner than the OEM carburetor. This caused the throttle linkage to bind when the air filter housing was fully torqued to specifications and kept the engine at full throttle. The MacGyver solution to the engine running only at full speed with no throttle control was to use three gaskets (instead of one) between the carburetor and the air filter housing to make up the difference. The governor is now free to do its job, the throttle control works and the engine runs as it should.

 

[fhiggenbottom]

Fred,My question is gov. spring still hooked ??I'm sending a pic but don't know if it will help.My engine(same) is upside down waiting for crank seal. best advice is get next to another 12.5 for comparison of linkage.The gov. spring shows up brown in the pics.Note: I put on carb. with elec solenoid to avoid flooding issues,of course you have to run a hot wire to it from switch.Your flooding is very common and can be very dangerous.Even old carbs leak when needle wears out.I'm a voice in the wilderness when it comes to this issue on gravity fed gas.Mfg should have long ago put a stop to this with an auto shutoff or at the very least a manual one...

Thanks for all your help! It was received with gratitude and appreciated. To mitigate further instances of carburetor leaks and the fire hazard associated with them I may take your advice and put a carburetor on the Kohler having an electric solenoid. I assume that to work properly it will require either wiring it into the starter switch or setting up a toggle switch.

 

[etopel]

The carb solenoid is an anti-dieseling device. It closes off the main jet when shutting down to prevent run-on. It does not prevent fuel from over filling the bowl if the needle leaks. When it over fills, it will come out the bowl vent inside the carb. From Gary's pictures it looks like there is an upturned intake elbow so the fuel can't get out that way so it runs into the engine. On the old Cubs with the air cleaner on the side the gas would run out that way and soak the air filter and run on the floor. If you want an automatic shutoff you can install a solenoid valve in the fuel line or else a manual valve that you have to remember to shut off each time.

 

[gary noblit]

Fred, congrats!! Did you put shut off in fuel line while you were at it..??? Ed,I believe I am mistaken and you're correct.

 

[fhiggenbottom]

Fred, congrats!! Did you put shut off in fuel line while you were at it..??? Ed,I believe I am mistaken and you're correct.

I did install out a shut off valve in the fuel line for safety and here's the final result with pictures of the Cub and snow blower and a shot giving you a view of the carb, new fuel filter, fuel lines and the shut off valve you can see just above the frame. And thanks Ed for saving me the time and cost of installing a solenoid equipped carb that wouldn't have provided the result I wanted.

 

[gary noblit]

Fred ,I apologize for the mistake,I do know better...It's a pain to shut off fuel every time but if you do you should never have gas in the crankcase again....nice clean looking machine !!

 

[fhiggenbottom]

Another reason for cheap Chinese carburetors not working properly on the Kohler 12.5 hp vertical shaft engine on the Cub Cadet 1330 and the work around.