Extended idling vs switching on and off

Sodo · Mar 25, 2014

Funny. I would not add hours to my tractor meter for something as useless as idleing. The number on the hour-meter is an important number and you're making it meaningless. You have to change fluids more often (if you maintain by the hour meter). And the next buyer gets to beat you down for that big number and scores an un-used tractor.

My dad used to let his Dumptruck idle because the air brakes leaked down, he at least had a reason but he could have fixed the leak. For all these years I've thought that people with diesel pickups let them idle (rather than shut them off) to pretend like they have a "big truck".

PapaPerk · Mar 26, 2014

Sodo said:
For all these years I've thought that people with diesel pickups let them idle (rather than shut them off) to pretend like they have a "big truck".

Exactly! It's more of a chest thumping issue than a mechanical issue! Lol

DieselMonk · Mar 26, 2014

I never found a reason to let my diesel car, tractors, dozer or the Case 580 idle for more than 5 mins here in Canada. Even my late 50's or early 60's dozer not. If there is a reason to idle to keep hydraulic or air pressure up, or if it is severe cold outside, I can understand. Other than that, a diesel with EGR will just carbon up. Those without EGR, won't have such a big problem with idling, but for what?! Just wastes fuel. Hogwash on washing down the cylinder walls I say, but then I don't let anything idle for more than 5 mins either.

newbury · Mar 28, 2014

Sodo said:
Funny. I would not add hours to my tractor meter for something as useless as idleing. The number on the hour-meter is an important number and you're making it meaningless. <snip>

On many small tractors, including my B7610 the number only reflect the hours as if the tractor was run at PTO speed. (For example if PTO speed was 3000 and you ran it for an hour at 1500 it might only show 1/2 hour) http://www.tractorbynet.com/forums/kubota-owning-operating/150221-b7610-hour-meter-tach-rpm.html.

Thus, the number is essentially meaningless for the unaware buyer.

newbury · Mar 28, 2014

Sodo said:
Funny. I would not add hours to my tractor meter for something as useless as idleing. The number on the hour-meter is an important number and you're making it meaningless. <snip>

On many small tractors, including my B7610, the number only reflect the hours as if the tractor was run at PTO speed. (For example if PTO speed was 3000 and you ran it for an hour at 1500 it might only show 1/2 hour) http://www.tractorbynet.com/forums/kubota-owning-operating/150221-b7610-hour-meter-tach-rpm.html.

Thus, the number is essentially meaningless for the unaware buyer.

/edit - the BX24 was reported as time based.

Sodo · Mar 28, 2014

newbury said:
Thus, the number is essentially meaningless for the unaware buyer.

That's very interesting, thank you for this useful correction.

To me that means the hour meter is MORE meaningful, shows the hours the tractor has been putting out "work".

jimpen · Mar 28, 2014

The other thing to consider:

I was taught that if the tractor is getting into the overheat range, such as you have been bush hogging a field to the point the that you clog the filters, that you shouldn't just shut it off. You should put it in a low idle and see if you can get some of the filters cleaned out. Then once it has cooled down some then shut it down and take care of the rest of the maintenance.

Or is this wrong?

Sodo · Mar 28, 2014

This is slightly off-topic as it regards the significant subject of "abrupt shutdown of a hard-working engine", not idle idling.

I would do what you say on any engine that has been working hard. Except I'd use a higher idle not low idle because it pumps more water, blows more air. Low idle could be so slow that it might boil over anyway. A higher idle (but not 'pulling a load') for a minute or two will cool your engine more evenly. A low idle might cool the area where cool water enters the engine, but if the flow is too low then the water is boiling before the exit. I'd say always hold a high idle at first. Maybe not a whole minute, at least 30 seconds?

Technically I think the components to focus on is cooling down the turbo on a turbocharged engine, and continuing the flow of oil to the turbo bearings and seals. Or cooling the exhaust valves on a gas engine with cooler combustion (rather than FIRE). I can't see how filters are involved, but I'm no expert.

In general industrial engines are heavy, thick iron, and there can be a lot of heat in the inside of the cylinder heads that is making its way out. If you shut it off too soon, the waterpump stops while the heat is still traveling out to the coolant. It needs moving coolant to take the heat out to the radiator. And it needs a spinning fan to blow the heat OUT of the radiator. Stopped coolant will boil.

If you shut it off abruptly it can boil over, or burp to the tank. I'd certainly let a hard-working engine get to a steady state (with the waterpump pumping, fan blowing) before shutting off the engine (=stopping the waterpump & fan).

However I bet modern tractors have evolved to have appropriately sized components that accommodate users who might shut down abruptly.

jimpen · Mar 28, 2014

Sodo said:
I can't see how filters are involved, but I'm no expert.

I have a filter/grate that is in front of the radiator to catch things like the milk weed flyers, etc. And then on the very front of the tractor hood there are the other grills that also catch stuff and get clogged as well. Those are the filters I'm talking about.