6.2 smoking ?

[96ccdd]

I know it is hard to pin point when a diesel starts smoking, however if indeed it is due to oil what typically goes it a 6.2 rings or valve seal ?

Thanks,

[DmaxMaverick]

Oil is oil. #2 is oil. Oil is fuel. Unless it's leaking oil, a lot, at the exhaust valve guide, it shouldn't smoke any more than it would normally. I have a friend who, years ago, ran straight waste oil for years, 100%, nearly every tank (only "fueled" up when out of town). His smoked less on waste oil than #2 (when smoke would be otherwise normal).

If it's consuming oil at an unusual rate, it could be excessive combustion blowby, pushing more crankcase oil vapor to the intake. A failed CDR can cause this, by not reducing crankcase vacuum at higher RPM's. The CDR rarely fails, but seems to get the blame fairly often.

Excessive smoke is normally an indicator of fuel quality, timing, injector and/or injection pump health. If it has more than 150K miles on it, advance the timing 1/16" at the timing mark (somewhat compensates for timing chain wear). If the injectors have more than 100K on them, they are also suspect. If you are burning enough oil to cause a lot of smoke (from the engine oil), you couldn't turn off the engine.

[96ccdd]

Gotta ya thanks for the reply. The motor has under 50k and has a new IP, it's in my CUCV. It smokes lightly at idle and under hard throttle the smoke increases but is blueish white. I did notice condensation in the oil fill tube. Just a note the truck is used offroad and never gets over 125* on the temp gauge. Could this be the main cause reason for the engine is not getting warm enough?

Thanks

[DmaxMaverick]

You need to verify the temp (mechanical gage or IR thermometer). 125° is way too cool, and won't help clear up any smoke. Make sure you have a good thermostat installed and the HPCA is working when it should.

Your timing may be retarded, which delays/reduces engine heat and smokes bluish-white (gray). The timing marks are often not accurate, especially on multiple generation separation, aftermarkets/overhauls.

[96ccdd]

You time is greatly appreciated. I just came in from messing with the K5,It appears my problems just got worse. I had a slight knock in the motor which has gotten louder and I have notice the oil pressure is 10psi at idle after warmed up, on a cold start it is 20psi. You thinks I could just drop the crank, have it polished and reinstall with new bearings?

Thanks again,

[DmaxMaverick]

You time is greatly appreciated. I just came in from messing with the K5,It appears my problems just got worse. I had a slight knock in the motor which has gotten louder and I have notice the oil pressure is 10psi at idle after warmed up, on a cold start it is 20psi. You thinks I could just drop the crank, have it polished and reinstall with new bearings?

Thanks again,

No. A problem with the crank and/or bearings is the last symptom of a bigger problem. Don't waste your time trying to patch Hoover Dam with chewing gum.

Depending on the amount of "condensation" in the oil, it may indicate a head gasket, head, or cylinder wall issue. Track your coolant usage, closely.

A bad injector(s) can cause horrible knocks (and smoke).

The low oil pressure may be an indicator. It depends on what it is, compared to what it was. Change the oil and inspect the waste carefully. Let it settle out any moisture, and see if there's any metal in it.

Do a cooling system pressure test, as well as a cylinder pressure (leak-down) test. This should identify any combustion chamber leakage.