There is such a lack of info here:
Rebuild? Do you mean new bores and pistons? All you mention is rings and ball hone.
Everything within spec? If this engine was not bored, did you really use a bore gauge (manual or digital?) to very carefully check for bore taper? (So far in my driving these since '79, I have found ONE engine not needing a bore when torn down). Are you adept at using a bore gauge?
If your bore is tapered, it ain't going to seat up. Then, there is the whole issue of proper bore size when machined. Most (almost all) machine shops ignore the tight new bore diameter relegated by VW. And, when they do that they pee away tens of thousands of motoring wear miles.
Direct questions, I know...but, no one learns anything here without realistic disclosure. And that has been a long standing problem as I see it.
As far as oil goes, I will tell you what worked for me: when I rebuilt 3 engines (bores, bearings, pistons, and rings) about 3 years ago, I broke them in on whatever light weight gas car oil I had sitting around. 10-30 and 10-40. Even my Prothe rings (you know...the ones which never seat?) seated up in short order. Only then did I switch to a 15-40 dino. Today's 15-40's (esp. Rotella) is just too slippery....too good.
When a former friend of mine worked as a field man for Cateprillar, the company issued an order that 15-40 was no longer to be used in all the lease units (this is out at the coal and gold mines west of here) because the oil was considered too slippery and was causing oil consumption in their new equipment. They said the rings would back off from the bores due to such good lubrication. They went to blanket 10-30.....year around. I am sure you will hear others tell you differently.
One last edit: what about the head? What sort of work was done to it? New valves....guides....properly reamed? How about valve stem seals? Very meticulous reinstalling the valve stems through the valve stem seals? I've seen and heard of guys totally spacing out installing valve stem seals.
Topic: 1.6NA Rebuild - Now blowing oil from Rear of Engine... (Read 8181 times)
