JD D170 Mower engine shutting off randomly

[raterus]

So I have a problem with my JD D170 mower that I haven't been able to fix yet. It only seems to be getting worse and more frequent. I don't usually have a problem getting the mower started, it starts up and runs great, sounds good, not starved for fuel, etc. However during running, the mower will just randomly shut off. I've checked and replaced both the fuel filter and fuel pump, and blown out the fuel lines just to rule out a fuel problem. I haven't dug into the carburetor yet, but seeing that I can start it fine and it runs, I don't really think there is a problem in there. It's also a new engine with only a couple of dozen hours on it now, and I don't use stale fuel either. I'm thinking that there may be an electrical problem that is kicking off the kill switch in the engine at random times. I just replaced the ignition switch (before this started happening) with a new OEM product, but I'm not sure how I'd go about testing that. I'm not really thinking that a new product direct from John Deere is the culprit either. Does anyone else have suggestions on what else I can check?

Thanks!

 

[Scrubcadet10]

If it's got that low of hours, i'd let a Dealer look at it

 

[Born2Mow]

2 ideas...

• Blocked fuel tank breather. Try taking the fuel cap off and see if it will crank 15 seconds later.
• On-again, Off-again seat safety switch.

But the best idea (since it's new) is for you not to touch it. Take it back to the dealer and demand a new one. You won't get one, but they will fix it in under 8 weeks !!

 

[StarTech]

Well considering that model has been in production since 2011 it may not be new.

I have seen the fuel solenoid on the carburetor to have loose terminals that make contact most times but you hit a bump just right shuts the engine as it looses contact.

Just a thought.

 

[bertsmobile1]

With these sorts of random problems I like to try & eliminate a full series of problems before digging in.
So you could start by removing the magnet kill wire then go mow
Problem goes away = safety switch fault
No difference then I swap out the carb solenoid with a bowl bolt or fit an old solenoid with the tip cut off
Problem goes away = bad solenoid or wiring to it as Star mentioned.
Still giving grief then it is fit a red spark tester to the engine , grab a can of carb cleaner and go mow.
When the engine starts to play up look at the spark tester .
If it stops flashing while the engine is still spinning = bad magneto
If it keeps on flashing to the bitter end then give the carb a quick shot of carb cleaner
Engine fire right up = fuel delivery problem
I have an old Tecumseh tank off an old 8 Hp single which I then hook up directly to the carb and run gravity feed
Problem goes away = carb is fine
Hook it to the fuel pump
Problem goes away = pump good & obstruction in the fuel tank or fuel line

 

[raterus]

Sorry for the delayed reply, I didn't get a chance to try any of this out until today. I think I've got a carb issue, I can manipulate some of the moving parts to keep the engine on. I've attached a picture that explains. There is a moving rod on the underside of the carb that currently is up when the engine off, when I turn the engine on this moves up and down. I'm guessing this is something that controls the intake of fuel. When I hear the engine about to crap out and push it up, I can keep it from turning off. Can someone advise me at this point what I can do to remedy this problem? I'm guessing cleaning the carb is probably in order.