Engine Performance (D3B or Case 580E)

My questions are; Are these engines running too "lean"? Could injectors be plugged? Should I be concerned?

Probably sound like crazy questions but have observed other diesel engines under load and they seem to get dark exhaust as load increases.

Thanks for your help!!!

Tom

At full power and/or peak torque, it is possible to set up a diesel engine for any desired amount of fuel. Too little, just right, too much. This also corrleates with an amount of smoking; none, a little gray smoke, lots of black clouds. Too little fuel will not hurt a diesel, it just won't develop full (potential) power.

Some engines come with the factory fuel settings deliberately turned down so they never reach or exceed the theoretical "best power mixure" of fuel to air for that particular engine. This is very common on ag tractors and construction equipment. It serves to maximize engine life and avoid over-powering the implements, hydraulics, transmission, etc. Also, it allows one basic engine core to be used in many applications. For example, the engine in my John Deere backhoe is rated at 89 horsepower, but the same engine goes over 110 horsepower in other machines like gensets and street sweepers.

Some guys have been known to "turn up the fuel" for more power. Carried too far, the exhaust produces black clouds. Some folks are gratified by the appearance of the black clouds, but such clouds are not indicative of any greater power beyond a certain point. But I suppose it looks cool.

I suspect that the D3B and 580E have the engines set up normally for less than max power, and that they are not expected to smoke, and that everything is running fine.

THANKS for the great explanation. As you can tell still learning about this kind of equipment. Just an observation on my part and just making sure everything was "set correctly" so as not to damage engines.

Along the same lines I was looking into adding turbochargers to each, especially the CAT D3B dozer. It has the 3204 engine. Any thoughts on doing something like this. The CASE has instructions in service manual, CAT makes not mention of it. Any insight??

Thanks
Tom

I have a turbocharger on my Deere backhoe. In this installation it provides something like 10% more horsepower and 20% more peak torque over the non-turbo version. It is supposed to help responsiveness and power in part load situations more than it acts as a gross power adder. It's hard for me to compare, since I haven't driven the non-turbo machine.

One annoying aspect is that you have to provide a spin-down/cool off time for the turbo, lest you damage the center bearing in the housing from oil coking. So the machine has to idle for 2 minutes in the machine shed before I can shut it down.

Turbocharger installations on the same basic engine can range from a simple bolt on to significant changes in the engine internals, including camshafts, cooling, oiling, pistons, cylinder heads and injectors. There is the choice of whether or not to provide aftercooling. It all depends on what the manufacturer wanted out of the installation.

If you look at www.cat.com, you will see Cat uses the same basic 6 cylinder engine in the D3G, D4G, and D5G. The horsepower ratings are 70, 80, and 99 horsepower. The D5G is turbocharged, the other two are not. Probably the D4 runs with more fuel than the D3.

In earlier days, they probably had the same situation with the 3204 (4 cylinder). A retrofit of a turbo for your D3B may be possible. But even for a basic installation, you need plumbing, oiling, intake, exhaust, injector, and injector pump mods. What else Cat may have included in the turbo version, is hard to say -- there may be internal engine changes as well.

I suspect the change-over would be cost-prohibitive unless you happend on a parted out D5. You would have to know what you were doing to set up the engine correctly.

Finally, engine characteristics are matched by the manufacturer to the weight and strength of the machine they are going into. In a tractive application like a dozer or plow tractor, there is no point in adding more horsepower just to spin the wheels or tracks against the load. (Sheer weight of the machine is usually the limitation in how hard you can push with a dozer).

Even if you did have enough traction to use the added horsepower, the increased stress on the driveline raises the possibility of blowing clutches/transmissions/drive sprockets, etc..

Every inveterate hot-rodder always wants "more power". But it can be hard to make effective use of it in most construction equipment.