4720 fast idle

[RoyJackson]

The bigger tractors do the same. They usually use coolant temperature for glow plug and high idle.
IIRC, the manual says, once the engine speed drops down to normal RPM, it's ready to go. And that's long before any temp would show on the gauge.

And I still don't rev it up past 1700 during the first few minutes after that.

Personally, I don't go to PTO RPM until the temperature gage starts indicating warm up. If I don't need the PTO, I'll start work after 5-10 minutes of fast (1500 RPM) idle

 

[birchbark]

The bigger tractors do the same. They usually use coolant temperature for glow plug and high idle.
IIRC, the manual says, once the engine speed drops down to normal RPM, it's ready to go. And that's long before any temp would show on the gauge.

And I still don't rev it up past 1700 during the first few minutes after that.

Ok guys and girls, I believe youæ±*e not understanding my issue. So letç—´ say itç—´-10c outside, tractor has been running for an hour and is at full operating temperature.. I turn it off for 2 minutes..I go to start it up and it goes to fast idle immediately..and stays there for a while.. just a pain in the *** and totally unnecessary. Thatç—´ the issue

 

[jd110]

I looked through all of the engine electronic control information. It does not say any exact parameter the computer is looking at to control idle speed. It only states that intake manifold air temp, coolant temp, fuel temp, turbo temps, exhaust temps, manifold air pressure sensor, and even temperature sensor internally in computer are all used to determine fuel settings. Tampering with how it interprets these readings will likely result in error codes and derating under some operating conditions.

 

[Bavarian]

Ok guys and girls, I believe youæ±*e not understanding my issue. So letç—´ say itç—´-10c outside, tractor has been running for an hour and is at full operating temperature.. I turn it off for 2 minutes..I go to start it up and it goes to fast idle immediately..and stays there for a while.. just a pain in the *** and totally unnecessary. Thatç—´ the issue

That's a whole different situation. Something definitely hung up in the electronics. It would be interesting if a computer could read the real time sensor signals when it's doing it. I don't know if a diagnosis software exists that works that way.

 

[dadiehl]

Green tractor talk has this conversation started 2/28/15. Someone on there explains where the sensor is. For the life of me I can’t get that post to copy and send it here. The posts title is 3 cylinder yanmar cold idle speed.

 

[Bavarian]

I took a screen shot. I got right there after I typed in the search on Google.

 

[beenthere]

That is pretty clear that the fast idle is intentional.. now will birchbark try to disable that feature?

 

[Bavarian]

I think his problem might be in the IP itself.

 

[jd110]

The 4720 does not have a Yanmar engine. It has a 4024 JD engine. It has 4 individual unit pumps and not one pump for all cylinders. Probably works off of same principal though.