John Deere 6220 ‘hunting’

[Tractorjoe]

Hi, not sure if anyone can help or had similar problems. Sorry for the long message!
I’ve got a John Deere 6220 which isn’t a common rail engine. When you run the tractor hard with the PTO running in warmer weather it starts ‘hunting’. It doesn’t return to idle, it sticks. If you turn it off and turn it back on, it doesn’t idle at 850.
I have changed the electronic lift pump, PTO speed sensor, engine speed sensor and all the fuel lines. It is also regularly serviced.
I have spoken to my John Deere dealer and they weren’t sure, said it could be the high pressure fuel pump but it doesn’t do this all the time.
I have had it plugged in, showing no error or fault codes where it is so intermittent. You can occasionally start it up in the morning and it’ll hunt in the yard when warming up on tick over.
I don’t know if this is linked to it but the battery light always comes on when you start it up. If you rev it up, the battery light will turn off. I have also changed the battery and alternator and that hasn’t solved it.

Any advice would be greatly appreciated.

Thanks, Joe.

 

[milkloss]

Suction control valve (scv)? Do a Google,

sounds like an expensive process of elimination so far!

 

[Tractorjoe]

Suction control valve (scv)? Do a Google,

sounds like an expensive process of elimination so far!

Thanks for the advise, I’ll have a google!

 

[milkloss]

Thanks for the advise, I’ll have a google!

copy and paste this into the search

scv jd hunting site:thefarmingforum.co.uk

 

[Tractortech]

Now Then...
If it isn't common rail, it won't have a suction control valve (SCV)!!
Have a look under the bonnet. See which fuel injection pump it has. There's a Stanadyne one with a mechanical throttle control or the all electric Stanadyne DE10..

 

[Bury the Trash]

Just use the advanced search but at tge bottom of the search area ' Google customs

John Deere 6630 hunting at idle

Tractor started hunting at idle at the end of last winter. I changed the fuel filters incase they were drawing air and it made little / no difference. The problem disappeared all summer and now it's started again. Any idea what the problem might be please....

thefarmingforum.co.uk

 

[Tractorjoe]

Now Then...
If it isn't common rail, it won't have a suction control valve (SCV)!!
Have a look under the bonnet. See which fuel injection pump it has. There's a Stanadyne one with a mechanical throttle control or the all electric Stanadyne DE10..

it’s the all electric control I have also change the potentiometer and speed sensor
[/QUOTE]

 

[Tractortech]

Do you have the engine management light flashing?? How many hours has it done?? Can you supply a picture of the engine side from further away so I can see the low pressure fuel hoses.
How long have you had this issue?? Did it happen suddenly or gradually??

 

[lexion780tt]

Those d10 pumps went very reliable, looks like its had a replacement plug put to it from ecu, chech all fuel pipes to it or just replace them there not expensive

Chech plug on ecu and wires to pump particularly the terminals on the 2 pin plug going into centre of injection pump.

If everything else is ok will need pump overhauling if you put a mug full of clean engine oil every fill up of fuel fill up seems to keep them going a bit longer

 

[Tractorjoe]

Do you have the engine management light flashing?? How many hours has it done?? Can you supply a picture of the engine side from further away so I can see the low pressure fuel hoses.
How long have you had this issue?? Did it happen suddenly or gradually??

tractor has done 9,700 hours

occasionally when it starts hunting The glow plug light will come on but it’s not all the time

it’s always done it ever since I’ve had it only when you work it hard on the PTO

 

[Tractordave]

It looks like your fuel return line orifice is missing. It may not be your problem but it’s definitely worth checking first. To test the theory put some locking pliers or a pipe clamp on the hose I’ve crossed. It will temporarily boost the inlet fuel pressure into the injection pump. If the hunting then goes away that could be your problem...

 

[Tractortech]

Ahhhhh, as I suspected, item 6 in the parts drawing (L167846 Orifice) . Without it you'll probably have low fuel pressure at the injection pump supply
It may be worth looking at the old hoses. To the untrained eye it just looks like a hose joint..

 

[Tractorjoe]

It looks like your fuel return line orifice is missing. It may not be your problem but it’s definitely worth checking first. To test the theory put some locking pliers or a pipe clamp on the hose I’ve crossed. It will temporarily boost the inlet fuel pressure into the injection pump. If the hunting then goes away that could be your problem...

Thanks for that, it’s been a big help. I’ll get the orifice!

 

[Tractorjoe]

Ahhhhh, as I suspected, item 6 in the parts drawing (L167846 Orifice) . Without it you'll probably have low fuel pressure at the injection pump supply
It may be worth looking at the old hoses. To the untrained eye it just looks like a hose joint..

Thanks, I really appreciate it the help. I’ll let you know how I get on.

 

[Tractorjoe]

Those d10 pumps went very reliable, looks like its had a replacement plug put to it from ecu, chech all fuel pipes to it or just replace them there not expensive

Chech plug on ecu and wires to pump particularly the terminals on the 2 pin plug going into centre of injection pump.

If everything else is ok will need pump overhauling if you put a mug full of clean engine oil every fill up of fuel fill up seems to keep them going a bit longer

Thank you

 

[Agri Spec Solicitor]

We had this problem when we were new to JD. Turned out it was the rotary control on the R panel which sets the max revs for a particular job. We had it set for 540E speed. May be irrelevant here of course but a cheap fix if it works.

 

[Tractordave]

Thanks for that, it’s been a big help. I’ll get the orifice!

Did it work?

 

[Tractorjoe]

Did it work?

Sorry, I meant all the information has been a big help. I’ll try what you said tomorrow. I’ll keep you updated on how it is!

 

[Tractordave]

Any success?!

 

[Tractorjoe]

I changed speed control sensor in the window seems to have fixed the problem