Caterpillar Engine - Faulty Injectors?

sb:649 ps:647

What it mean ?

are engine normally run while running under different loading conditions ?

Guest ###

yes, the engine runs normally under different loads. but i see this black smoke is not normal and i would like to know the causes.which part in the engine may be need to replace .

Diesel engines normally black smoke due to rich mix. Before replacing anything, maybe someone could adjust/clean pump and injectors. This engine is a 4 cycle diesel, am I right? Clean and adjust, and you may be alright. Black smoke is actually pretty usual to see in such condition. As you may know, blue smoke is bad (indicates oil burning, internal wear, etc).

Yea its a four stroke in question here with very expensive electronically controlled unit injectors. The injectors do however still require to have the height adjusted mechanically. After that (if memory serves), the rest is done via the lap top linked to the engine.

Its a pretty neat set up, you can cut out each injector and diagnose there condition while the engine is running with no load!

It seems to me that a little training is needed. The class will be much more economical than purchasing a set of injectors that are not needed.

Take the engine and bring it up to operating temp. Preferbly under some load. put a dab of grease on each section of the exhaust manifold in line with the exhaust port. the ones that burn of fast usually are ok and the others are poor combustion. You can also use a heat gun to pyrometer to test the heat of each exhaust port.

From what you listed there doesn't appear to be any problem with your injectors. What loads are being applied, what altitude.

Have you checked filter restriction?

Your B series engine can and should be diagnosed with a lap top and the correct link/program. DO THIS FIRST rather than being one of those random parts changers.

Most larger dealers offer a course on these engines, there you can purchase the program and link as well as receive proper training on maintenance and troubleshooting.

I'm with Tim.

I have found restricted air flow due to plugged air filters will result in power loss and excessive dark smoke. Also I would guess it would be possible that the injectors could give this condition as well if the injectors are slightly plugged not giving atomization of the fuel. If the fuel squirted in it would not burn efficiently and the smoke could be unburnt fuel. If you have 13000 hrs on the engine, perhaps you should be considering some PM anyway. As for your temperatures, I would tackle the lowest temps first.

Good Luck!

Josh

Put in a new paper air filter or clean the oil type filter. Sample the fuel for specification compatability. I overhaul the injectors and fuel pumps at 15,000 hours as normal service for everything in my (Duetz) fleet. Your engine has reached most of it's trouble free service life, I would also consider a replacement or rebuild at this time because issues can mount in an expensive, extended downtime sort of way.

A couple more points on your B series Cat. The valves and injectors should be re-set after 250 hour break in and every 4000 hours there after if you are running maintenance based on hours. The recommended method is by amount of fuel consumed, your engine keeps this information stored in its programing.

Seems to me I've seen typical overhaul times for heavy equipment engines quoted at 10,000 hours normally. If this is constant load stationary equipment, overhaul intervals are usually extended 30 to 50%.

Black smoke, according to my sources, means excess pressure in the fuel lines to the injectors. (Old truckers' trick to boost power.)

Any Proper Engineer who knows his diesels will tell you: -

White smoke = cold engine (Normal at Start Up)

Black Smoke = Overload.

However black smoke can also be due to one or more injectors leaking and thus applying more fuel that can be burnt in the cylinder. At 13,000 hours I would not think this to be the case, unless the fuel being supplied is of poor quality.

Can you check the output load, i.e. if electrical generator as load what KW and allow about 3 to 5 % for copper, Iron and windage losses, other equipment may require strain guage on the output shaft.

Have a look at Turbocharger RPM, charge air pressure and temps into and out of T/C. Compare all operating parameters against the readings taken for the new engine when it was on the test bed. This will tell you what to expect

Get me more particulars and I will be more than happy to ether send you the correct Cat maintenance schedule in PDF or just quote the information you need.

First tell us the engines application; primary generator, standby, propulsion engine, etc.

If possible, record the total fuel consumed (its available on the digital readout)

Normal load in Kw.