Strange Problem with John Deere Tractor

Reply

  #1  
Old 05-21-20, 02:33 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Strange Problem with John Deere Tractor

I have a 20 year old JD LX279 garden tractor with a 17HP liquid cooled Kawasaki V-twin. Two weeks ago I was mowing (~1 hr) and had to shut it off before I finished mowing. When I started it back up, it was running a little rough, but cleared up after a few minutes. However, about 10 minutes after I started it back up, the engine started to die. If I gave it partial choke, it would run fine, and sometimes would run well for 30 seconds or so with the choke off, but would then begin to die again.

The next day I took the carb off and took it all apart and cleaned all the jets and passages, using a pin and Gumout carb spray. I reassembled the carb and installed it on the engine. The engine started up and appeared to run fine (no choke required except to start it). Yesterday I mowed again and it ran fine for 15-20 minutes. Then it started to die. Again, giving it partial choke would keep it running. I finished mowing by holding the choke lever with one hand while steering with the other.

Today I purchased a can of Gumout Multi-System Tune-Up (liquid) and put 2.5 oz into the gas tank (~2.5 gallons of fuel). Again, the engine started right up and ran normally for about 15 minutes, then, just like someone flipped a switch, the engine started to die unless I gave it partial choke.

At this point, I'm stumped. The fuel is fresh this year, and I always put Stab-il in the gas in the Fall before I put the tractor away (put it in before last mowing). I'm assuming the spark is okay since the engine runs reasonably well with the choke partially on (when it acts up). It seems to act up when the engine gets hot, as it will run fine for the first 15-20 minutes.

I apologize for the long post, but I would appreciate any advice on how to solve the problem.
 
Sponsored Links
  #2  
Old 05-21-20, 02:45 PM
G
Member
Join Date: Jun 2006
Location: United States
Posts: 2,445
Received 5 Votes on 5 Posts
Try loosening the fuel cap it sounds like it is not venting properly, if that helps then clean or replace the cap. Have a good one. Geo
 
  #3  
Old 05-21-20, 02:48 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Thanks Geo, I'll try that. However, why would it only act up when the engine is hot?

Update: I just tried mowing with the gas cap off. Engine was running great. Approximately 15 minutes after I started, suddenly it lost power and would only run with the choke partially on. I turned the engine off, let it sit for 5-10 minutes and it started right up and is running normally again, although I don't know for how long.
 

Last edited by Bob14525; 05-21-20 at 03:21 PM. Reason: update
  #4  
Old 05-21-20, 04:07 PM
W
Member
Join Date: Apr 2003
Location: Ohio
Posts: 1,777
Received 8 Votes on 8 Posts
Have you ever changed the fuel pump?
 
  #5  
Old 05-21-20, 04:10 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Thanks for the reply. No, it's the original pump. Is this a common problem, where they work for awhile, then stop working? Letting the engine cool for a few minutes lets it run again.
 

Last edited by Bob14525; 05-21-20 at 04:32 PM.
  #6  
Old 05-21-20, 06:44 PM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
Is this a common problem
Yeah, but for different reasons.

Fuel flow restricted = let's it run until the reserve of fuel is used, then it dies. As it sits the fuel flows past the restriction and it repeats itself. Plugged or collapsed lines, plugged tank cap vent, dirt in carburetor or float inlet needle hanging up.

Vapor locking from either excessive heat source (like exhaust) or poor line pressure from fuel pump performance. Also fuel quality can affect it.

Ignition = coil heating up after running a short time, then failing is fairly common. Also if equipped with a fuel solenoid and a dead battery = shuts down the carburetor.

There are other things, but this will get you started.
 
  #7  
Old 05-21-20, 06:56 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Thanks very much for the reply. After hearing your comments, I'm leaning towards replacing the fuel pump. I hate "shotgunning" it, throwing parts at it, but the pump is relatively inexpensive. It does have a fuel solenoid, but the battery isn't dead. Although it's the original battery, it still cranks over okay.
 
  #8  
Old 05-21-20, 07:04 PM
W
Member
Join Date: Apr 2003
Location: Ohio
Posts: 1,777
Received 8 Votes on 8 Posts
I agree with MarbobJ, Since all of my tractors are older than 20 years I have had all of the things he mentioned happen to me at one time or another with one or several of them. The one that trips my trigger on yours is that it runs with the choke partially closed. That one of minet got fixed with a new fuel pump. I had two that had intermittent failure of the ignition module. With those two, the engine got hot and the module just stopped me, no partial closed choke would get me anywhere until it cooled off. I think a new fuel pump will solve a lot of problems for you, if not right now. very soon. Let us know!
 
  #9  
Old 05-21-20, 07:20 PM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
It does have a fuel solenoid, but the battery isn't dead
The fuel solenoid can fail internally. Having current from a battery to operate it is one part of the equation.
 
  #10  
Old 05-22-20, 02:14 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 17,371
Received 30 Votes on 25 Posts
I would suspect 20 year old fuel lines collapsing internally or the fuel filter or pump.
 
  #11  
Old 05-22-20, 04:21 AM
B
Member
Join Date: Oct 2015
Location: Ct.,USA
Posts: 1,529
Received 60 Votes on 53 Posts
Does it have a fuel filter that can be replaced?
 
  #12  
Old 05-22-20, 05:34 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Cheese, thanks for the reply. Yes, it does have a replaceable fuel filter. I'll check the fuel lines for signs of collapsing and order a new fuel pump and filter. The fuel solenoid is working. With the engine running at a moderate speed, if I pull the wire off the solenoid, it begins to die. As soon as I put the wire back on, it starts to run again. I tried this while the engine was hot and acting up, so I don't think the solenoid is intermittent.

I'll report back after I get a new pump and filter (will take some time as I'll order them online). Thanks for all your replies. I totally forgot that this engine had a fuel pump.
 
  #13  
Old 05-22-20, 04:39 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 17,371
Received 30 Votes on 25 Posts
You might just need $5 worth of fuel line. You can't tell if it 's collapsing internally by inspecting it.
 
  #14  
Old 05-23-20, 04:43 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Where would I go to buy new fuel lines? Are they usually all the same diameter, or are there many different sizes? I just checked Amazon, and they sell bulk fuel line hose. They have both 1/4 & 3/8 ID hose. To determine the size, I assume you measure the diameter of the "pipe" that the hose attaches to, not including the larger diameter nipple. Is that correct?
 
  #15  
Old 05-23-20, 06:07 AM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
Just take a piece of what you have to an auto parts or small engine shop and match it up.
 
  #16  
Old 05-23-20, 03:26 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Update

Today I replaced the fuel filter and replaced all the fuel hose from the fuel tank to the filter, filter to fuel pump, and pump to carb. On the JD LX279, it's a pretty big job as you need to remove the "body" of the tractor. The body is heavy and my wife was struggling with it while helping me remove it and reinstall it when I was done installing the new lines.

Unfortunately, the engine behaves the same. I was out mowing for 10 minutes and it started to die. Again, I can bring it back by giving it partial choke. One observation I made. When the engine started running poorly, I limped back to my garage using the choke. I looked at the new fuel filter and it looked like there was very little gas in the filter compared to the amount that was in it when I first started it up and it was running well. At this point, I'm 99% sure that the fuel pump is the culprit, somehow failing to pump properly when it gets hot. I have a new pump on order from Amazon. Hopefully, it will get here sometime next week. I'll report back when the new pump is installed.
 
  #17  
Old 06-01-20, 04:16 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Another Update

Well, the fuel pump came in about half an hour ago. I pulled out the old one and installed the new one. I was certain this was the problem, as there was virtually no fuel in the fuel filter when the engine started running badly and requiring partial choke to run. Last week, while waiting for the fuel pump to arrive, I tried to mow with the tractor. It usually would run for ~10 min before it required choking to stay running. Last time, it would only run with the choke on even when cold. It runs the same way now with the new fuel pump. I see a little gas in the fuel filter, although not as much as I thought there should be. How much fuel should be in the fuel filter with the engine running?

Tomorrow, I'll pull the fuel line from the pump to the carb and see if it's pumping. It's possible that the new pump is defective, although unlikely. If the fuel pump is working, I'll replace the carb. I ordered a replacement carb when I was "shotgunning" the problem. It came in a couple of days ago, but I didn't install it because I was sure the pump was the problem.

I'll report back tomorrow with the results of further work (testing pump and possibly replacing the carb). There's virtually nothing left. I've replaced the entire fuel line from the tank to the carb, new fuel filter, and new fuel pump. Needless to say, I'm very frustrated at this point.
 
  #18  
Old 06-01-20, 05:48 PM
W
Member
Join Date: Apr 2003
Location: Ohio
Posts: 1,777
Received 8 Votes on 8 Posts
John Deere

Did you check the flow of the fuel coming from the tank, at least at its first length of hose before it attaches to the fuel pump or whatever? I have found stuff floating around that will flow by gravity and then suck whatever is in there to where it blocks the line inside the tank right when you need it the most. If that comes up zero. Use another tank of fuel and line to bypass everything you can. That way you can narrow it down a LOT as to where your problem is.
 
  #19  
Old 06-02-20, 04:22 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Thanks for the reply. I was thinking the same thing overnight. I'm going to pull the fuel line from the carb and stick it in a jar. I'll then turn over the engine and see if fuel is being pumped out of the tank. If that is inconclusive, I could try removing the gas tank from my snowblower (gravity feed) and feed that directly to the carb to see if it runs. If it runs well, then I know it's a fuel delivery problem. I hope it's not something wrong with the fuel pickup in the tank, as the tractor "body" is a bear to remove (very heavy and awkward to remove).
 
  #20  
Old 06-02-20, 04:42 AM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
Before replacing the carburetor, I would check the spark when it dies. A lot points to a fuel problem, but a compromised ignition can work better in a richer mixture environment. The fifteen minute duration aligns with a limping ignition.
 
  #21  
Old 06-02-20, 05:16 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Thanks for the reply. I just came in from testing the fuel pump. I believe the fuel system is working okay. I ran a hose from the output of the fuel pump into a 32 oz glass jar. I ran the engine for approximately 10 seconds and it nearly filled the jar. I have no way of measuring the fuel pressure, but the volume seems okay.
 
  #22  
Old 06-02-20, 06:49 AM
T
Member
Join Date: Jun 2012
Posts: 949
Received 6 Votes on 6 Posts
This is a pretty common problem, running with the choke on indicates there's fuel but it's not pulling enough up through the metering jet. Replace the carb, you can find a $20 aftermarket unit online.
 
  #23  
Old 06-02-20, 08:33 AM
W
Member
Join Date: Apr 2003
Location: Ohio
Posts: 1,777
Received 8 Votes on 8 Posts
Have you done any work to the valves? Before I bought any more new parts, I would certainly get a compression check done first, My last engine that acted like yours was caused by a chunk of carbon under an exhaust valve that was preventing the intake stroke from creating enough vacuum to get fuel TO the cylinder and then allowing it to fire off and stay running. After 20 years a lot can happen that you just don't see. A valve job on a small engine is not that tough to do, even for a novice.
Your fuel tank is probably plastic, but if not, metal tanks are notorius for creating rust, chunks of which float around until you put a drag on the fluid and suck it over to the filter screens. I took and old metal tank that was driving me nuts doing that to a radiator shop. problem solved.
 
  #24  
Old 06-02-20, 01:23 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Update #3

I was tied up most of the morning and only got a chance to get back to the tractor after lunch. I pulled the plugs and checked them. They looked pretty good with little wear and no carbon. I adjusted the gap (was very slightly too large) and put the plugs back in. I then proceeded to replace the carb. After replacing the carb, I had to crank the engine for 10 seconds or so to fill the float bowl (expected). It started right up and ran great. It idled smoothly and was running great. I put the hood back on and went out to mow. It ran great for about 15 minutes, then started to act up again, requiring partial choke to keep it running at speed. What does seem different this time is that after giving it partial choke for about 15 seconds, I can then open the choke and it will run fine for several minutes, then starts acting up again. I repeated this procedure for several times before I finally finished mowing.

So, it seems to run better in that I don't have to give it choke continuously, just every few minutes after warming up. I have a compression gauge somewhere. I'll try to find it and check the compression. Since it appears to be heat related, I'm wondering if it could be a bad ignition module. However, an ignition module is ~$250, so I don't want to buy one unless I'm reasonably sure that's the problem. If I can find my compression gauge, I'll report back what I find.

Thanks for all the ideas, guys!
 
  #25  
Old 06-02-20, 03:23 PM
W
Member
Join Date: Apr 2003
Location: Ohio
Posts: 1,777
Received 8 Votes on 8 Posts
Every bad ignition module I had to replace was because it would shut the engine off completely. Cool off and start again until it got hot again, and bang. shut down. Someone else can chime in and say it happened to them. (kept running with partial choke,) but not me. After 20 years, it needs a valve job regardless.
 
  #26  
Old 06-03-20, 11:38 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
I agree with you regarding what is likely to happen if the ignition module craps out. It was just a thought since it seems to be temperature related. I can mow for 10-15 minutes and then it's just like someone flipped a switch. The revs start to drop and the engine begins to sputter. If I give it partial choke, the engine comes back to life at or near full revs. BTW, I was unable to find my compression gauge. I haven't used it in over 30 years, and I don't remember if I loaned it to someone, or what happened to it. I'm about at the point of purchasing a new tractor. I've received nearly 20 years of faithful service from this tractor and maybe it's time to retire it. I have over 1 acre of land to mow, and at my age (71), it's difficult to do it with a 20" non-propelled push mower.
 
  #27  
Old 06-03-20, 11:49 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 17,371
Received 30 Votes on 25 Posts
It's a fuel issue, no need for compression tests or valve jobs, you have an issue with fuel delivery to the cylinders. The fact that it runs fine for several minutes and then begins to falter and the condition is reversed by applying choke proves there is a fuel problem. Could be foreign matter blocking the pickup tube in the tank, a restriction in the lines, a tank venting problem, something lodged in the carburetor inlet, or a blockage in the carburetor itself.
 
  #28  
Old 06-03-20, 12:42 PM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Cheese, I agree with you 100% that it's a fuel issue. However, I have replaced the entire fuel system. I've replaced all the fuel line from the tank to the carb, new fuel filter, new fuel pump, and new carb. The only thing I haven't changed is the pickup in the fuel tank. What seems strange about it being the fuel system, is why does it only act up after the tractor has been running for 10-15 minutes? It's just like someone flipped a switch and it suddenly starts dying. I was convinced it was the fuel pump, thinking that there may have been a tear in the diaphragm and it somehow changed with heat, but changing the pump didn't fix it.
 
  #29  
Old 06-03-20, 01:24 PM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
I would check the spark when it starts acting up. It's easy enough to do and just basic diagnosis.

But I wouldn't replace any more parts without knowing they're faulty.
 
  #30  
Old Yesterday, 10:24 AM
Bob14525's Avatar
Member
Thread Starter
Join Date: Jun 2013
Location: USA
Posts: 1,504
Received 15 Votes on 10 Posts
Final Update

Well, I've solved my tractor problem. I went out this morning and bought a new JD X330. The local dealer was running a sale ($300 off), and surprisingly, they gave me $400 for my old tractor. I just have to wait for them to deliver it next week.

I had a final thought on my old tractor. I'm wondering if possibly the intake manifold has a hairline crack in it. When the engine heats up, the crack gets bigger, letting in air. The additional air would make the mixture leaner, thus requiring some choke. If it is that, it would be an expensive repair and it more than I'm willing to do for a 20 year old tractor.

Thanks for everyone's assistance and ideas. It was certainly an experience and I appreciate all the help.
 
  #31  
Old Yesterday, 02:27 PM
M
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 4,098
Received 9 Votes on 9 Posts
That is a solution that works. You should be good for another 20 years. Take care.,
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: