John Deere 850. 1765 hours. Used almost exclusively for mowing lawn on my daddy's place. Pretty big lawn. Maybe 7 acers or so? Last year and this year it has gotten to where it loses power and then stops after an hour or so. Wait a bit and it will fire right up, mow for a while, then do the same thing again. Cooling system has been gone through, flushed, new thermostat, new hoses, new radiator, new antifreeze. Fuel tank was just cleaned out, fuel lines blown out, new filter, fresh fuel. Nasty slimy stuff in tank along with some water. I am starting to think it may a worn injector pump. Anyone here have similar problems?
John Deere 850
- Thread starter ElbertR
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bmaverick
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- Yanmar YM2610 ■YANMAR GURU■ EXTRAORDINAIRE
Your JD850 is really a Yanmar YM2500 in JD green paint.
You did mention a new filter. Was this fuel or air? Power loose is common with a clogged air filter.
Additionally, these Yanmars tend to run hotter when 15W40 engine oil is used. The oil traps heat in the engine longer than the recommended SAE 10W30 diesel engine oil. If the 15W40 or thick oil is used, the head tends to warp or crack.
Our machines use the same 3T80 engine as well. I have a YM2610 with the meter just turning 1800 hours.
The two known cleaners for Japan diesel engines are
#1. Gumout Multi-Fuel System cleaner
#2 Seafoam
Both are about the same price. I was doing Seafoam until I witnessed the Gumout doing a better job on a JD1050 (Yanmar YM4300)
If you need free downloadable manuals or the parts network being 1/2 the cost of Deere, then join the YTOG here,
main groups.io Group
*Yanmar Tractor Owners Group.* **US models, Gray market models, Cub Cadet models, RK models, even our green siblings known as Deere's. ** *A valuable source for owners of Yanmar tractors.* * * *If you would like to join our group, then click on the +Join This Group button below left. *NOTE: A...
yanmar-tractor-owners.groups.io
thepumpguysc
Elite Member
Try changing the fuel filter again.. it’s a minimal cost.
My motor is the 3T80-J. I have the serial number written down but not right at hand so I can't tell you just what year it was built. I should have said filters. Both fuel and air filters were changed. I changed the air filter not long ago and the fuel filter was changed by a tractor repair shop on Thursday and the tractor was returned to me just yesterday. I use Seafoam in every motor I have here from push lawn mower and rototiller to mama's riding mower, our sxs, in both tractors and once in a while even in our vehicles.Your JD850 is really a Yanmar YM2500 in JD green paint.
You did mention a new filter. Was this fuel or air? Power loose is common with a clogged air filter.
Additionally, these Yanmars tend to run hotter when 15W40 engine oil is used. The oil traps heat in the engine longer than the recommended SAE 10W30 diesel engine oil. If the 15W40 or thick oil is used, the head tends to warp or crack.
Our machines use the same 3T80 engine as well. I have a YM2610 with the meter just turning 1800 hours.
The two known cleaners for Japan diesel engines are
#1. Gumout Multi-Fuel System cleaner
#2 Seafoam
Both are about the same price. I was doing Seafoam until I witnessed the Gumout doing a better job on a JD1050 (Yanmar YM4300)
If you need free downloadable manuals or the parts network being 1/2 the cost of Deere, then join the YTOG here,
main groups.io Group
*Yanmar Tractor Owners Group.* **US models, Gray market models, Cub Cadet models, RK models, even our green siblings known as Deere's. ** *A valuable source for owners of Yanmar tractors.* * * *If you would like to join our group, then click on the +Join This Group button below left. *NOTE: A...
I do not believe it is an overheating problem as the temp light does not come on. Not saying it isn't an overheat problem because it sure acts like one but there is the same amount of coolant in the overflow bottle when I start and when it quits. I've been pretty diligent to open the hood to check the coolant level both in the radiator and in the overflow bottle. I also do not believe it is a cracked block or head as the oil is not milky from water or coolant getting in and as I said, the amount of coolant in the overflow bottle is stable.
Now, after all that was said, I have been known to be wrong a lot
Fuel filter was just changed a couple days ago. I can see the fuel filter in the glass. It is still white. I may change it again because you suggested it but it looks mighty clean.
Air filter looks about as clean as the day I put it in but I may change that out again also.
I just got the thing back from the repair shop yesterday (Fri). Hooked the mower up and within hour and a half or so it started losing power and quit.
I'm at my wits end here trying to diagnose this problem. I see a similar problem on the GreenTractor forums from back in 2015 but the OP never did come back to say what it was or if he fixed the problem.
Thank you for the links, Maverick. I have joined the Yanmar group there.
I really hate to spend the bucks but Diesel Pro looks like may have a pump, a reman, for $795. I will probably give them a call on Monday right after I call the repair shop...
Thank you for the replies I really appreciate it.
thepumpguysc
Elite Member
How about loosening the cap on the fuel tank when it STARTS to slow down.??
U could be pulling a vacuum..
U could be pulling a vacuum..
thepumpguysc
Elite Member
Why don’t you let me take a look atchr pump before u go spending $800. bones.??
I’m not saying it’s not possible that the heat from the engine and fuel isn’t effecting the metal inside the pump but it’s HIGHLY UNLIKELY.. ESPECIALLY if it starts and runs good for the 1st hour or so..
Try loosening the cap..
I’m not saying it’s not possible that the heat from the engine and fuel isn’t effecting the metal inside the pump but it’s HIGHLY UNLIKELY.. ESPECIALLY if it starts and runs good for the 1st hour or so..
Try loosening the cap..
I had the same suggestion over on the Green Tractor Talk forums. And with the tank already having had algae in it the vent could very well be plugged.
If I decide to start messing with the injector pump I will most certainly send it to you.
All I have to do now is wait for the rains to stop so I can go mow for a while and see if it's just a simple fix like a plugged fuel tank vent.
bmaverick
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The only time I ever seen the over heating lamp come on was well after the engine lost power, suggesting and then the head warped towards engine failure. When the lamp comes on, it's way too late to save the engine.
BEFORE you spend the $800 on a fuel injector pump, it would be wise to have yours rebuilt by the member who mentioned to replace the fuel filter a 2nd time.
Member here as thepumpguysc is,
Mike the pump guy - Master Injection Pump Rebuilder
For Japan made tractors, namely many of the brands including Yanmar for fuel pumps.
Mike can be reached on our message board from time-to-time, The best way is via email he typical monitors very often at:
thepumpguyscATaol.com
(replace the AT with the @ symbol when emailing please)
- Mike has 35+ years in the industry with injection pumps and hydraulic systems.
- He is very well versed in the JIS and SAE standards for parts to ensure proper components are used for rebuilds.
- From Sunny South Carolina.
- When sending parts via mail, please be sure to have insurance for a bit more than what you can find it new due to carrier issues that 'could' happen.
There are many positive testimonies on many of the Industrial Equipment, Heavy Equipment, diesel boating, tractor and other forums on his work and professionalism.
Shout out to The Pump Guy | Heavy Equipment Forums
(2) Thepumpguysc rocks - TractorByNet
Timing fuel injection pump - Yesterday's Tractors (yesterdaystractors.com)
Ford 3600 leaking from where fuel inlet meets injector | My Tractor Forum
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pmsmechanic
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I've run into this problem before. On a diesel tractor there just happened to be a leather glove floating around in the fuel tank. Every once in a wile it would float over the fuel outlet inside the fuel tank and shut the engine off. After a while you could start the engine again.
The other time was on a swather where the fuel cap had been left off for a while. Every once in a while a dead moth would float over the intake and starve the engine for fuel.
Both were easy fixes. On the tractor I just fished the glove out and problem solved. The swather was a little more messy. I ended up removing the fuel outlet fitting and installing a bit of rolled up aluminum window screen into the fuel hole. That also solved the problem as it was impossible to drain all of the moth's out of the tank.
I hope that some something like this is an easy cheap fix for you.
The other time was on a swather where the fuel cap had been left off for a while. Every once in a while a dead moth would float over the intake and starve the engine for fuel.
Both were easy fixes. On the tractor I just fished the glove out and problem solved. The swather was a little more messy. I ended up removing the fuel outlet fitting and installing a bit of rolled up aluminum window screen into the fuel hole. That also solved the problem as it was impossible to drain all of the moth's out of the tank.
I hope that some something like this is an easy cheap fix for you.
I just solved a similar issue with my JD 430, long story short the fuel shut off solenoid was it, occasionally it would not give me the "click" when the key was turned. I've always thought of this solenoid as either on (working) or off never in between. It has two windings in it and after getting hot the second winding started to close partially giving me the same low power issues you are having too.
Good luck!
Good luck!