603 run without turbo installed
 

I am reviving an old project and want to find out as much as I can about this engine a scrap yard find. I wish to run this smoking engine without the exhaust manifold on to observe each cylinder. I have the exhaust manifold off and turbo so can I

1) block the turbo oil supply line

2) just feed the supply back to the sump directly

3) choke some oil supply and returnto sump.

I have a spareoil supply I could modify.

In theory the oil pump should have more than enough flow to care for the turbo feed just returning to the sump but I'd double check the oil pressure once it had started just in case. You could also just chuck an ordinary bolt in place of the banjo bolt on the oil filter housing (assuming 603s have them) as well

The turbo is not "pressurized" with oil when the engine runs, the oil basically just passes straight through to the pan. There's no reason you can't just have the oil flow straight to the pan to test what you want. 603's have the oil feed threaded into the block, not tapped off the filter housing with a banjo.

Ok I'll just pipe it back to the sump.

On another topic why would exhaust valve number 1 be oil soaked and all others dry.

Bad valve seal maybe? That would be my first guess.

New valve seal and guide. Maybe need to do another leak down test on number 1.