JD 185 wont start

Hi, I have a John Deere 185 with a single cylinder 17 hp FC540V-CS00 engine. It was running fine, no issues at all. Went to start it up, and it wont start. Cranks and cranks, tries to start, but wont. Actually, I did get it going, and it ran great like normal. Shut it off to try to restart, and it wont restart again. This is why I am unsure of what could be wrong, knowing that it runs fine once started, but its the starting issue. It is getting visible spark via plug removed and resting against engine block, but I don't know if it is sufficient spark to start it? Fuel is fresh and it is getting fuel to the carb, and plug is wet, but not soaked. I put in a new plug (NGKBPR5ES) I have since removed the plug to inspect it after attempting to start, and it has some black carbon deposits on it. I tried a little starting fluid as well. I have cranked and cranked, as it seems like it is so close to starting,with random fires, but it wont. I can hear the combustion, and see obvious signs of smoke coming from the exhaust during this time. After searching the internet for this problem, I am more confused now then initially. Appears as though this is not an uncommon problem with this mower. Seems that Coil and/or Ignitor keep coming up as the most common fixes. Would a bad coil still provide enough spark such that it runs fine, but make it almost impossible to start? I also found information about a Starter Improvement Relay kit that seemed to help a lot of guys. Does anyone know if this kit would increase the speed of the starter, as it kind of seems like the flywheel may not be spinning fast enough to start the engine. Or is this kit solely to make sure the starter engages the flywheel? Any suggestions, questions, or did I miss anything in my rambling?

Spinning the engine faster is not going to fix your problem.

I would make sure the choke is working the way it should.

Check compression. You can borrow a tester from most parts stores.
If it was the coil it would not run fine once you get it started.

When it starts does it have all the power it should with the blades on?

Check all the safety switchers the electrical schematic below should give you some idea what to looking out for, if you not understand a schematic or wiring you will be better off taken it into the shop.

Carscw said:

Spinning the engine faster is not going to fix your problem.

I would make sure the choke is working the way it should.

Check compression. You can borrow a tester from most parts stores.
If it was the coil it would not run fine once you get it started.

When it starts does it have all the power it should with the blades on?

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1. ok, thanks
2. I have removed the air cleaner and been manually moving the choke and throttle, When I feather the throttle, that's when it most sounds like it will start. I am familiar with non electrical small engine carbs, but not necessarily this particular one. There is a wire connected to the bottom of it...
3. I will check compression, but it could take a while for me to get. It ran perfect once started, and with the blades engaged as well. So I guess I was assuming the compression was good.

EngineMan said:

Check all the safety switchers the electrical schematic below should give you some idea what to looking out for, if you not understand a schematic or wiring you will be better off taken it into the shop.

Click to expand...

I understand the schematics, but not fully confident on being able to check every one. I will try to enlist the help of someone a little more knowledgable about how to test each switch. I have a volt meter, but not confident with it. I would love to take it to a shop, but do not want to invest what could be several hundred dollars when I can just buy a used working mower for a similar price.


This gets me thinking though. I used to be able to move the mower in neutral fairly easily, but moving it around since it stopped starting has become a chore, such like the transmission is still engaged... I will check into this as my next step. Would the transmission being engaged make it sound like it wants to start, and even fire, but not fully start? Please anyone with a thought- comment

Is it fitted with a fuel solenoid, if so check it out make sure you hear a click when you turn key to run, because you say you are getting spark.

EngineMan said:

Is it fitted with a fuel solenoid, if so check it out make sure you hear a click when you turn key to run, because you say you are getting spark.

Click to expand...

I disconnected the fuel line past the fuel pump, and it pumps when I turn the key. I tried disconnecting the wire that is attached to the bottom of the carb too, no change. but yes, appears to be getting fuel to the cylinder...

If its getting fuel to the cylinder, then recheck the spark.

EngineMan said:

If its getting fuel to the cylinder, then recheck the spark.

Click to expand...

It has spark, but im not sure if its enough. Would this make sense, that it is getting spark, enough to run "normal" If it can get started, but has a very difficult time starting? The coil is old and rusty, so I am trying to decide if I should even bother buying a spark tester, or just buy the coil, since it seems like this or the ignitor is the most common part to fail on this engine, according to everything im reading anyways.

Attempt to find the coil that is... discontinued. Looking for part # 21121-2059. Every website I find that says they have one, does not. I have a call into the local John deere dealer, will see what they say, or perhaps theres a replacement part number hopefully.