4720 still don't understand pre-heat...help

[9973720wb19]

i have a MY 2011 4720 and the owners manual says to pre-heat (push in the key) for no more than 10 secs. However, the pre-heat light is still on after 10-15 secs (now with my mowes, I wait until that goes out and then you start it) AND the LED dashboard read out in the 4720 still says "wait to start"...i don't want to go too long pass 10 secs at the risk of damaging something, but when I do go a bit longer, it seems to kick over easier. should I hold in the key until the pre-heat light goes out and/or it stops scrolling "wait" ...what do you guys do?

 

[arlen4720]

i have a MY 2011 4720 and the owners manual says to pre-heat (push in the key) for no more than 10 secs. However, the pre-heat light is still on after 10-15 secs (now with my mowes, I wait until that goes out and then you start it) AND the LED dashboard read out in the 4720 still says "wait to start"...i don't want to go too long pass 10 secs at the risk of damaging something, but when I do go a bit longer, it seems to kick over easier. should I hold in the key until the pre-heat light goes out and/or it stops scrolling "wait" ...what do you guys do?

My 2012 4720 manual says 10-15 seconds for temps as low as 0 deg F and 15-30 seconds for below 0 deg F. However, I've noticed that when it's cold, it automatically turns on the glow plugs ( or intake heater, whatever). I find it's not necessary to manually do it. I just got the 4720 in may, so I've only tried to start it down to about 20 deg. I also leave the throttle at the idle position. The manual says to start it with the lever at 1/3. The engine revs way up, and doesn't start as good if I do that.
I also noticed that it will start at fast idle automatically when it's cold.
To answer your question directly, I don't think you will hurt it keeping the glow plugs on for up to 30 sec, but it seems to me that it handles itself automatically pretty well.
I think the light will never go out when you are holding the key in; it will always say "wait".
I would just let it do it's thing first, then when the light goes out, press the key for another 10 sec if you think it helps.

 

[PioneerMan]

My older 4320 only heats the grids as I push in the key. I thought I heard yours has a time control. Much like my old truck, there is a temp sensor so it will preheat a certain amount for various temps. It should be a simple manifold heater during wait to start. I have repeated the cycle with no bad effects when temps are 0-30.

 

[jcalla]

My 2010 4720 goes into heat mode when the temp drops and I get the wait statement on the display. I can depress the key also but usually don't.

 

[Chuck on lake]

I have wondered the same thing with my 3720. It is inside and never goes below freezing. I hold the key in before starting and the "wait to start" never cancels. I usually keep it in until the OH door opens (12 secs?) but the wait light never goes off. It seems to start fine although I think some of the battery punch has drained by using the preheat.

 

[kford13]

I thought that pushing in the key cycled the air intake heater as well. For cold starts though, nothing has done as much for me as installing the block heater. Even when it was -40, started right up. I am thinking about installing the fuel heater though... anyone got it?

 

[JD 4520]

I thought that pushing in the key cycled the air intake heater as well. For cold starts though, nothing has done as much for me as installing the block heater. Even when it was -40, started right up. I am thinking about installing the fuel heater though... anyone got it?

Where do you live in 40 below?

 

[arlen4720]

I thought that pushing in the key cycled the air intake heater as well. For cold starts though, nothing has done as much for me as installing the block heater. Even when it was -40, started right up. I am thinking about installing the fuel heater though... anyone got it?

I didn't know there was such an option. I was kind of kicking around the tranny heater though, anyone got one of those?

 

[kford13]

For your tranny heater, looks like AR94493 Transmission Oil Heater
Requires AR95434 Cord Set, R34557 Clamp and (2) R44302, Self Locking Straps.

 

[kford13]

Where do you live in 40 below?

Colorado.. Looking at my good ol weather station at the house to refresh my memory... we hit -27 which resulted in -45 with wind chill.