looks like my 5.3 has been run with far took much oil in it. there is a lot of smoke and oil coming out of places it shouldn't, is this the result? are there any other consequenses of overfilling? many thanks for any replies

 

What a good question.

It would depend on how much overfull it is/has been. A litre or 2, although NOT a good practice, should not do any real harm.

I worked out a long time ago, that a V12 with its 10ltr oil capacity, would need to be at least 5ltrs overfull befor the crankshaft would "dip" in the oil and reek havoc.

#1 reason for sudden oil leaks is a blocked breather. Thats the filter thingy INSIDE the alloy elbow attached to the front of the LH cylinder head. Down here that filter is given to the dog as a toy, and the rubber elbow refitted without such a thing in there. Then the PCV valve may be blocked/hissy, and the engine cannot suck the fumes etc out, as designed. That will cause the crankcase to "pressurise" and oil will leak from places that no one thought possible.

#2, is the rubber bung on the front of the timing cover on the RH side, just below the headgasket line. This plugs a hole that is used to release the timing chain tensioner spring during rebuilds, and that bung goes hard, shrinks, fall out, or inside the engine, and oil leaks out. NOT under pressure, just leaks out with the engine running and makes a mess.

#3 is the "D" rubbers at the rear of each camcover, and the camcover gaskets themselves. When these things let go, there is one hell of a mess.

The list goes on, but I will stop at the most common.

You will need to establish EXACTLY where the leak is originating from. So cleaan it down, run the engine, look around, find the source, then the fix is so simple.

Of course, dip the oil, check the level, and if overfull by a HUGE amount, drain some out. Then clean up the mess and go look for the leaks as mentioned above.

The V12 is a VERY forgiving engine, so panic not.

 

Wonderfull and uplifting advice thanks. I'm worried the valves may be knackered!

 

It a V12, have faith my man.

It will be some silly little thing.

These engines run near on 100PSI oil pressure when cold, and close to 80PSI when hot. So double and more your tyre pressure, and that will have oil squirting out at a crazy rate if a small seal or something fails.

One item I forgot.

At the rear of the engine are 2 oil sender units, THEY LEAK badly. Mainly the small one that operates the idiot light.