DCS
Bronze Member
I have always heard that it is not good to "bog" down a diesel engine. What damage could occur to an engine by doing this?
"Bogging" down the engine
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chrisjbell
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The good news is that diesels do OK "bogged" because the way they ignite the air fuel mixture is pretty much like what you get when you hear knocking or pinging in a gas engine.
Better not to do it to any engine - means you're overloading it. Keep the revs up high enough for what you are doing so that doesn't happen.
There are those that suggest that running engines at lower RPM saves 'em from extra wear. I'm not of that school personally but can see where they're coming from.
Better not to do it to any engine - means you're overloading it. Keep the revs up high enough for what you are doing so that doesn't happen.
There are those that suggest that running engines at lower RPM saves 'em from extra wear. I'm not of that school personally but can see where they're coming from.
RoyJackson
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Worst thing I've ever heard (and who knows...maybe this is an old wives tale...or an old mechanic's tale) is bogging an engine can result in pounding the main bearings.
This would result in ovaling or flat spots at the bottom of the main (crankshaft) bearings, thus destroying their effectiveness and, ultimately, the crank.
Remember, the bearings require a thin oil film to work.
It's easy to prevent..just shift to a lower gear.
This would result in ovaling or flat spots at the bottom of the main (crankshaft) bearings, thus destroying their effectiveness and, ultimately, the crank.
Remember, the bearings require a thin oil film to work.
It's easy to prevent..just shift to a lower gear.
I also try to avoid bogging down diesel engines, but sometimes it happens and you can't help it.
I often find it happens when towing a heavy trailer in a high gear and you start going uphill. The engine dies down, and then recovers.
It is probably better to keep it revved up.
I often find it happens when towing a heavy trailer in a high gear and you start going uphill. The engine dies down, and then recovers.
It is probably better to keep it revved up.
Volfandt
Veteran Member
Several bad things happen when you bog down an engine. In both gas & diesel engines the crank and rod bearings bear the brunt of the pounding and additionally when a diesel bogs down the gov will call for more fuel to get the rpm's back up and all that additional fuel won't get combusted, it'll accumilate on the cylinder walls breaking down the thin film of lubricating oil and also collect in the oil pan diluting the oil.
Some engines are designed to run all day long at 2500 rpm, others at 3000 and still others at 3600 rpm. With tractors, it's best to "work" a tractor at it's designed rated pto speed.
In any case, it tain't good to continually bog an engine down when working it.
Some engines are designed to run all day long at 2500 rpm, others at 3000 and still others at 3600 rpm. With tractors, it's best to "work" a tractor at it's designed rated pto speed.
In any case, it tain't good to continually bog an engine down when working it.
jbrumberg
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DCS:
Shift to a lower gear and increase your RPM's. When your tractor is bogging down it is talking to you; it will happen on ocassion. Jay
Shift to a lower gear and increase your RPM's. When your tractor is bogging down it is talking to you; it will happen on ocassion. Jay
There are two things that are similar. One is when you have the throttle at 1/2 or 2/3 and you start to do something requiring more power. The RPM's will sag down some and the gov will start to give it more power. You can hear the extra power being generated. At that point the rpm's will stabilize or rise. That's normal even with a slight brown or black haze to the exhaust.
Bogging down is technically defined as the condition that exists when you pull the throttle down more and the engine is not able to increase the RPM's against the given load.
SO, if you are hitting a heavy load and hear the gov add fuel and you pull the throttle lever down and the RPM's don't change (or continue to drop), you are seriously overloading the engine. You can hear and feel the difference as it has a lower frequency with pronounced pounding. That is bogging it down and that is not good. The long term damage is typically a broken crank, spun bearing, bent rod, melted piston or even a thrown rod. Diesels are tough, but everything has it's limits. After a while you will get a feel for them and will add more throttle sooner and/or drop a gear.
When it happens on occasion, it's no big deal. It's when you make a practice of operating in a bogged condition that damage accumulates until your wallet bleeds.
jb
Bogging down is technically defined as the condition that exists when you pull the throttle down more and the engine is not able to increase the RPM's against the given load.
SO, if you are hitting a heavy load and hear the gov add fuel and you pull the throttle lever down and the RPM's don't change (or continue to drop), you are seriously overloading the engine. You can hear and feel the difference as it has a lower frequency with pronounced pounding. That is bogging it down and that is not good. The long term damage is typically a broken crank, spun bearing, bent rod, melted piston or even a thrown rod. Diesels are tough, but everything has it's limits. After a while you will get a feel for them and will add more throttle sooner and/or drop a gear.
When it happens on occasion, it's no big deal. It's when you make a practice of operating in a bogged condition that damage accumulates until your wallet bleeds.
jb
jbrumberg
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jb:
One of the best descriptions of bogging down a tractor and its consequences I have read
. Jay
One of the best descriptions of bogging down a tractor and its consequences I have read
. Jay
firedog
Gold Member
In addition to all previous statements; bogging causes the cylinder temperatures to increase dramatically. As the RPM drops the boost pressures also drops decreasing the amount of air (in non-turbo aspirated engines the effect is much the same - low mainfold pressure) and fuel delivery increases the cylinder temps skyrocket as well as the turbo temp.
bogging for long periods can do tremendous damage. Countless times I've had to drop a few gears when pulling thru the mountains. (sometimes even against a strong headwind)
bogging for long periods can do tremendous damage. Countless times I've had to drop a few gears when pulling thru the mountains. (sometimes even against a strong headwind)