Check your fuel pump on top of the one fuel filter . When the pump starts to go bad it doesn't have enough pressure anymore and that's why you are getting the error codes and loose engine performance.

 

I will check it out Tks
,

 

Not sure of the actual error codes now but we had de rating problems the same as your describing, it turned out to be after much messing around to be a engine sensor on the block that was faulty. Just get your technician to check agco fault finding list for what throws the codes you put up. That's how our problem was resolved.
Cheers Matt

 

tech and shop foreman claim faulty engine sensor makes engine run rough at 1800 rpm.

 

Will do

 

Same problem with a r76 check the ground wire for just in front of that pump on the engine frame and solved the problem

 

Mechanic rode with me with laptop hooked up and code would pop up but nothing changed on laptop...pressures remained constant. After it through 4 codes it derated and fuel pressure dropped. After a chat with tech on phone he changed fuel filters and pressures were more stable so back to town he went. Everything worked well then 2 hrs later 14 codes and a derate at almost the exact same time as last night. I will check all of the grounds and clean screen in fuel line. Then not sure

 

That will probably be the one, the symptoms you are explaining sound exactly the same as ours. And you can tell the tech or foreman that it did derate the engine to 1500 rpm. I would push they try changing it. We did exactly what you did re changing fuel filters, and she went along okay for a bit then derated again.
We drained all the fuel out of tank and cleaned out the already clean tank filter, you name it I think we did it, and turned out to be the engine sensor, I think there is actually 2, but they got the right one first up.

 

You don't add any weird additives to your fuel that aren't recommended for fuel do you? Had one guy with a power issues that added some kind of oil to his fuel for lubrication and it kept plugging up the filters on his 9795 MF with Tier 3 SISU engine. Worked in everything else on his farm, but the filters are so fine one these new engines they would just plug. Used new fuel and fixed problem. Can't remember what he used ATF or something like that.

 

Yes Howes fuel conditioner and it worked for the first 600 hrs with no problems.

 

Have they checked actual pressure, have seen cases with plastic filings in the tank causing fuel restrictions. Always good to see the actual pressure on a gauge to verify what the computer is saying.

 

I got a feeling plastic might have been the cause of all this frustration. The last thing we did was drain tank through fuel line and I blew air back through line to see if flow would improve it didn't improve flow. In the process of blowing air I must have blown fuel intake screen off of fitting so we didn't ever find screen to see if it was plugged. New screen was installed along with another set of new filters and 500 acres so far with no codes.

 

We were blessed with a fuel tank on our 67 that didnt

Have the plastic cuttings removed after they cut the holes in the tank for the fuel lines. They look like black plastic drill bit cuttings. They plugged up the fuel tank screen, the screen in the line about half way between the tank and fuel pumps and I think there is another in line strainer right before the fuel filters. We had to drain the fuel tank 3 times I believe. Check all of these strainers. It took us over a year as more cuttings just kept coming. We were getting the same codes and engine would derate. Can't tell you how many fuel filters we changed. You might also send in a fuel filter and have it analyzed. This all occurred after we ran it a year.

 

There was a few pieces of plastic in screen before filters but not enough to restrict flow. I will look to see if we missed that other filter. We have a pile of snow so we have time to check it out.

 

No filters other than screen and two cartridge filters in engine bay. I will drain tank through line and see if flow slows.

 

I drained tank and removed fitting from tank and found no screen in tank. I pumped fuel through fuel line back and forth and flow is good. This is starting to get me frustrated, my crop is under a foot of snow and when it's go time if it ever comes I have no time to trouble shoot...harvest window is going to be really small.

 

Is there a lift pump on this 2013 S77? They used to have one on top of fuel filter on previous models but I don't see one on this one.

 

Did they actually change the engine sensor, or did you just run with their theory on it running rough at 1800 rpm or whatever?

 

All sensors three of them and a solenoid were changed one of them twice as new one was faulty. Drained fuel flushed lines, changed filters twice and now waiting for snow to go and crop to dry to try it again. I am now thinking it has to be a supply or lift pump getting weak if there is one, the problem started when fuel level was getting low around 6 pm it would throw codes then it would gradually start throwing codes early each day then the last day every time I used more than 60 % power it would derate.

 

Still sounds exactly like our plastic cuttings problem. There is a screen on the fitting that goes in the bottom of the tank. An inline screen that is half way down the left side of the machine kinda right behind the left front tire and I think there is another before the fuel filters. Next time it does it take the fuel line off before the screen on the left side and see what your flow is. Ours always occurred when the tank was getting low as the cutting would settle around the screen that is in the tank connected to the fitting that has the fuel line on it.

 

There is a screen in tank and one just before filters in engine bay but none on side of machine, I had all of the lines off no filter in between. There were a few plastic pieces on screen the first time I removed it covering less than 10% of screen. Were is the lift pump?

 

On my R62 I had the similiar problem with power. Changed filiter and cleaned screens. Don't about the codes but they sound similiar to the ones I had. It was a bad wire in the wiring haraness.. Tech found it by moving wires around.

 

That's good to here. Hope you get it all finished up. Just took off the last of my canola here today, went through the combine really nice but the moisture must be close to 20%

 

Did you ever fix this problem? I Have a S77 with a engine code: Rail pressure controller positive deviation
CODE SPN/FMI: 157/ 15
Changed filters, fuel screen, both rail sensors, and a sensor on the injection pump. all recommended by the techs I talked to on the phone. still derating to 1500rpm. Trying to see where to go from here?