Yanmar vs JD 4024T

[9973720wb19]

I traded in my 2008 3720 for a 2011 4720. Enjoying the 4720 but had a few questions about this engine:
1) I don't think my 3720 had glow plug, but rather an air heater for cold starting...after 10secs of warming with the key...it fired up quicker than i could take my fingers off the key.
2) my 4720 on the other hand, starts fine with key warming, but not as fast. where my 3720 gave a more quick "gas engine car start", the 4720 is more diesel and tractor like...it cranks a bit.

I really liked how the Yanmar kicked over, why is there a difference?
Just the nature of the engine?
Different heating methods?
Would some Yanmars crank like the JD engine?

 

[AKfish]

Neither engine has glow plugs. Both have an intake air "preheater".

First question in mind, are you holding the warmup key "in" for an equal count time?

Second thought, the 3720 engine was ~92cu.in. and the 4720 is around ~145cu.in.

Gonna take more "warm air" to convince those 145cu.in. that it's OK to start than the smaller Yanmar.

AKfish

If you're concerned that the 4720 is a little "cranky" starting in the colder temps - consider a block heater, too.

 

[9973720wb19]

Yup, holding the key in the same amount of time. That was one of my thoughts/hopes, that the bigger engine just needs more/longer drain on the battery to fire. thanks for the reply.

 

[cdaledave89]

Ok, this is similar to another thread about cold starting and I didn't see anybody mention this in either thread. My 2009 4520 automatically preheats (or turns on the glow plugs) when I turn the key to the ON position. The display on the dash says WAIT and the glow plug light stays on until it is properly preheated. Then you can turn the key and it will start. Depending on the temperature, it will say WAIT up to maybe 30 seconds before it's OK to start. I have never had a problem starting the tractor down to temperatures as low as 3 degrees F, even without a trickle charger on the battery or a block heater. Seems to me that JD has made it idiot-proof if you just wait until the WAIT message goes away. Maybe not all model-years work this way?

 

[AKfish]

I went here: John Deere - Parts Catalog

I checked 2 of the 3 engines listed fuel systems and yep... the Deere powerplants for the 4000 series 20's are glow plugged!

AKfish

 

[sunnyside360]

I went here: John Deere - Parts Catalog

I checked 2 of the 3 engines listed fuel systems and yep... the Deere powerplants for the 4000 series 20's are glow plugged!

AKfish

I just wish JD would update the owner/operator manuals. Manual's for both of my 4320's (2007 and 2010) specify intake air heater as shown below. Just a pet peeve of mine and there are other areas of the manuals that need updated. They still make great tractors or I wouldn't buy them.


9. For cold weather starting, use the intake air heater system. Activate the intake air heater system by pushing in the ignition key switch with the key, and holding it there for the required time:

10 - 15 seconds for temperatures as low as -18ｰC (0ｰF).

15 - 30 seconds for temperatures below -18ｰC (0ｰF).

 

[jenkinsph]

My experience with the Yanmar and Deere engines in the 110 and 4520 is that the Yanmar(110) starts up with a quick turn of the key in any weather, the Deere needs coaxing in 40 F and below.

 

[sunnyside360]

My experience with the Yanmar and Deere engines in the 110 and 4520 is that the Yanmar(110) starts up with a quick turn of the key in any weather, the Deere needs coaxing in 40 F and below.

Yep, my experience exactly. My 3720 with Yanmar engine fires up on first or second compression stroke and the 4320's with the 4024T JD engines have to turn over several times/seconds to start.

 

[9973720wb19]

Ok, this is similar to another thread about cold starting and I didn't see anybody mention this in either thread. My 2009 4520 automatically preheats (or turns on the glow plugs) when I turn the key to the ON position. The display on the dash says WAIT and the glow plug light stays on until it is properly preheated. Then you can turn the key and it will start. Depending on the temperature, it will say WAIT up to maybe 30 seconds before it's OK to start. I have never had a problem starting the tractor down to temperatures as low as 3 degrees F, even without a trickle charger on the battery or a block heater. Seems to me that JD has made it idiot-proof if you just wait until the WAIT message goes away. Maybe not all model-years work this way?

so you should wait until the Wait message goes away??...I thought the manual said do not hold the key in for more than 10 secs. or it will cause damage?