MG Car Repair: Pumping oil through the exhaust, leak down tester, mg midget

Question
I have a 66 MG midget in my shop that I am repairing for a retired friend. He told me that it started pumping oil out of the exhaust (3 quarts in 10 miles) the muffler does have oil in it. The engine was rebuilt less that 300 miles ago by the current owner and I do not have even a slight clue where to start looking for this problem.

Answer
Hi Todd,

If it is blowing blue smoke out the exhaust and has condensed oil in the tail pipe You need to first look at the PCV valve and look for over filled oil pan and if they are ok run a dry compression test and then a wet compression test as a test for rings. A leak-down test will work if you have a leak-down tester.

However, 300 miles is not usually enough time on a rebuild to completely seat the rings. This depends a lot on what kind of rebuild too. Was it bored with new pistons? Or just honed and new rings? and were the rings chrome faced? Did a professional do the rebuild or the owner himself?

If the owner (who did the rebuild) was not a professional, you may have to ask him if he installed the rings and if he put the ring marking "UP" or did he even know rings are marked? and how did he hone the cylinders? Did he mike the bores or have it done? Did he check ring end gap? Did he stagger the end gaps?

These are the most common errors I seen owner re-builders make.

Howard