oil burning 96 TDI Help?

My 96 TDI is burning oil (one quart in 60 miles) smoking badly. The cylinder compression is 500 pounds straight across(all four). The turbo was just replaced 200 miles ago. Lots of crankcase pressure. The turbo appears to be tight (feeling normal at intake side). I installed a quater inch copper line to supply oil to the turbo. The previous line fed from the end of the camshaft(low oil pressure there)oil pressure in engine is 10 pounds at idle hot and 28 pounds at freeway speeds, seems low to me. the oil pressure at the camshaft is only 10 pounds at freeway speeds, five pounds at idle. This is the third turbo in 1000 miles. I am thinking my bearings at the mains (original) are worn badly and lack of oil pressure is killing the turbos. Power is low as well. Rings were replaced two turbos ago. Pistons looked good. Taper in the cylinder was only .002. Any comments out there in TDI land? Thanks
Joe

How many miles on the car/motor?

You are probably on the right track. However, before condemmning the main bearings, I would replace the oil pump.

More than likely, the low oil pressure is destrying the turbo shaft seals. Check the lower intercooler hose for oil.

Tony

You never say how many miles. That is important information. Let's assume if not alot, it's mileage with poor maintenance.

Where the oil pressure goes..

1. The intermediate shaft bearings.
2. The oil pump.

Where the oil goes...
1. The rings.
2. The turbo.
3. The CCV.

Do you really mean three turbos in ONE THOUSAND MILES?? Where the heck are you getting turbos? China?

As for the oil pressure, check the pressure directly at the oil filter housing and then at the oil galley on the head. If there much of a pressure difference, it's the intermediate shaft bearings, which wear terribly. Low pressure, you can blame on everything else, including oil pump, bearings, etc. Other than that, it's possible you've got a blown head gasket.

As for the taper, I wouldn't put an engine together with .002" taper. I would also check ring end gap at the top of the cylinder. If it's over .024", I'd be getting some o.s. pistons and a bore. If you square up the cylinder honing it, you'll end up with new ring end-gap at it's limit.

Sleeving is an option, but only if the pistons are in reasonably good condition. Use quality domestic sleeves and shoulder the bottom of the bore.

The wear factor on the oil pump is going to follow the cylinder wear, to a degree. The older AHU pumps aren't as robust as the post 99.5 cars. It is suspect.

The biggest oil pressure killer on these cars are the intermediate shaft bearings. Remove the shaft's seal support and give the shaft a wiggle. I bet it rattles in the hole.

INtermediate shaft bearing installation is not easy with the engine in place, but can be done. Seriously, I wouldn't be working in the car. I'd be pulling the engine.

Get a quality turbo and the proper line. Don't use copper tube. It's just wrong.